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-Copyright (c) 1988, 1989 Hans-J. Boehm, Alan J. Demers
-Copyright (c) 1991-1996 by Xerox Corporation.  All rights reserved.
-Copyright (c) 1996-1999 by Silicon Graphics.  All rights reserved.
-Copyright (c) 1999-2001 by Hewlett-Packard Company. All rights reserved.
-
-The file linux_threads.c is also
-Copyright (c) 1998 by Fergus Henderson.  All rights reserved.
-
-The files Makefile.am, and configure.in are
-Copyright (c) 2001 by Red Hat Inc. All rights reserved.
-
-Several files supporting GNU-style builds are copyrighted by the Free
-Software Foundation, and carry a different license from that given
-below.
-
-THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
-OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
-
-Permission is hereby granted to use or copy this program
-for any purpose,  provided the above notices are retained on all copies.
-Permission to modify the code and to distribute modified code is granted,
-provided the above notices are retained, and a notice that the code was
-modified is included with the above copyright notice.
-
-A few of the files needed to use the GNU-style build procedure come with
-slightly different licenses, though they are all similar in spirit.  A few
-are GPL'ed, but with an exception that should cover all uses in the
-collector.  (If you are concerned about such things, I recommend you look
-at the notice in config.guess or ltmain.sh.)
-
-This is version 6.1alpha5 of a conservative garbage collector for C and C++.
-
-You might find a more recent version of this at
-
-http://www.hpl.hp.com/personal/Hans_Boehm/gc
-
-OVERVIEW
-
-    This is intended to be a general purpose, garbage collecting storage
-allocator.  The algorithms used are described in:
-
-Boehm, H., and M. Weiser, "Garbage Collection in an Uncooperative Environment",
-Software Practice & Experience, September 1988, pp. 807-820.
-
-Boehm, H., A. Demers, and S. Shenker, "Mostly Parallel Garbage Collection",
-Proceedings of the ACM SIGPLAN '91 Conference on Programming Language Design
-and Implementation, SIGPLAN Notices 26, 6 (June 1991), pp. 157-164.
-
-Boehm, H., "Space Efficient Conservative Garbage Collection", Proceedings
-of the ACM SIGPLAN '91 Conference on Programming Language Design and
-Implementation, SIGPLAN Notices 28, 6 (June 1993), pp. 197-206.
-
-Boehm H., "Reducing Garbage Collector Cache Misses", Proceedings of the
-2000 International Symposium on Memory Management.
-
-  Possible interactions between the collector and optimizing compilers are
-discussed in
-
-Boehm, H., and D. Chase, "A Proposal for GC-safe C Compilation",
-The Journal of C Language Translation 4, 2 (December 1992).
-
-and
-
-Boehm H., "Simple GC-safe Compilation", Proceedings
-of the ACM SIGPLAN '96 Conference on Programming Language Design and
-Implementation.
-
-(Some of these are also available from
-http://www.hpl.hp.com/personal/Hans_Boehm/papers/, among other places.)
-
-  Unlike the collector described in the second reference, this collector
-operates either with the mutator stopped during the entire collection
-(default) or incrementally during allocations.  (The latter is supported
-on only a few machines.)  On the most common platforms, it can be built
-with or without thread support.  On a few platforms, it can take advantage
-of a multiprocessor to speed up garbage collection.
-
-  Many of the ideas underlying the collector have previously been explored
-by others.  Notably, some of the run-time systems developed at Xerox PARC
-in the early 1980s conservatively scanned thread stacks to locate possible
-pointers (cf. Paul Rovner, "On Adding Garbage Collection and Runtime Types
-to a Strongly-Typed Statically Checked, Concurrent Language"  Xerox PARC
-CSL 84-7).  Doug McIlroy wrote a simpler fully conservative collector that
-was part of version 8 UNIX (tm), but appears to not have received
-widespread use.
-
-  Rudimentary tools for use of the collector as a leak detector are included
-(see http://www.hpl.hp.com/personal/Hans_Boehm/gc/leak.html),
-as is a fairly sophisticated string package "cord" that makes use of the
-collector.  (See doc/README.cords and H.-J. Boehm, R. Atkinson, and M. Plass,
-"Ropes: An Alternative to Strings", Software Practice and Experience 25, 12
-(December 1995), pp. 1315-1330.  This is very similar to the "rope" package
-in Xerox Cedar, or the "rope" package in the SGI STL or the g++ distribution.)
-
-Further collector documantation can be found at
-
-http://www.hpl.hp.com/personal/Hans_Boehm/gc
-
-
-GENERAL DESCRIPTION
-
-  This is a garbage collecting storage allocator that is intended to be
-used as a plug-in replacement for C's malloc.
-
-  Since the collector does not require pointers to be tagged, it does not
-attempt to ensure that all inaccessible storage is reclaimed.  However,
-in our experience, it is typically more successful at reclaiming unused
-memory than most C programs using explicit deallocation.  Unlike manually
-introduced leaks, the amount of unreclaimed memory typically stays
-bounded.
-
-  In the following, an "object" is defined to be a region of memory allocated
-by the routines described below.  
-
-  Any objects not intended to be collected must be pointed to either
-from other such accessible objects, or from the registers,
-stack, data, or statically allocated bss segments.  Pointers from
-the stack or registers may point to anywhere inside an object.
-The same is true for heap pointers if the collector is compiled with
- ALL_INTERIOR_POINTERS defined, as is now the default.
-
-Compiling without ALL_INTERIOR_POINTERS may reduce accidental retention
-of garbage objects, by requiring pointers from the heap to to the beginning
-of an object.  But this no longer appears to be a significant
-issue for most programs.
-
-There are a number of routines which modify the pointer recognition
-algorithm.  GC_register_displacement allows certain interior pointers
-to be recognized even if ALL_INTERIOR_POINTERS is nor defined.
-GC_malloc_ignore_off_page allows some pointers into the middle of large objects
-to be disregarded, greatly reducing the probablility of accidental
-retention of large objects.  For most purposes it seems best to compile
-with ALL_INTERIOR_POINTERS and to use GC_malloc_ignore_off_page if
-you get collector warnings from allocations of very large objects.
-See README.debugging for details.
-
-  WARNING: pointers inside memory allocated by the standard "malloc" are not
-seen by the garbage collector.  Thus objects pointed to only from such a
-region may be prematurely deallocated.  It is thus suggested that the
-standard "malloc" be used only for memory regions, such as I/O buffers, that
-are guaranteed not to contain pointers to garbage collectable memory.
-Pointers in C language automatic, static, or register variables,
-are correctly recognized.  (Note that GC_malloc_uncollectable has semantics
-similar to standard malloc, but allocates objects that are traced by the
-collector.)
-
-  WARNING: the collector does not always know how to find pointers in data
-areas that are associated with dynamic libraries.  This is easy to
-remedy IF you know how to find those data areas on your operating
-system (see GC_add_roots).  Code for doing this under SunOS, IRIX 5.X and 6.X,
-HP/UX, Alpha OSF/1, Linux, and win32 is included and used by default.  (See
-README.win32 for win32 details.)  On other systems pointers from dynamic
-library data areas may not be considered by the collector.
-If you're writing a program that depends on the collector scanning
-dynamic library data areas, it may be a good idea to include at least
-one call to GC_is_visible() to ensure that those areas are visible
-to the collector.
-
-  Note that the garbage collector does not need to be informed of shared
-read-only data.  However if the shared library mechanism can introduce
-discontiguous data areas that may contain pointers, then the collector does
-need to be informed.
-
-  Signal processing for most signals may be deferred during collection,
-and during uninterruptible parts of the allocation process.
-Like standard ANSI C mallocs, by default it is unsafe to invoke
-malloc (and other GC routines) from a signal handler while another
-malloc call may be in progress. Removing -DNO_SIGNALS from Makefile
-attempts to remedy that.  But that may not be reliable with a compiler that
-substantially reorders memory operations inside GC_malloc.
-
-  The allocator/collector can also be configured for thread-safe operation.
-(Full signal safety can also be achieved, but only at the cost of two system
-calls per malloc, which is usually unacceptable.)
-WARNING: the collector does not guarantee to scan thread-local storage
-(e.g. of the kind accessed with pthread_getspecific()).  The collector
-does scan thread stacks, though, so generally the best solution is to
-ensure that any pointers stored in thread-local storage are also
-stored on the thread's stack for the duration of their lifetime.
-(This is arguably a longstanding bug, but it hasn't been fixed yet.)
-
-INSTALLATION AND PORTABILITY
-
-  As distributed, the macro SILENT is defined in Makefile.
-In the event of problems, this can be removed to obtain a moderate
-amount of descriptive output for each collection.
-(The given statistics exhibit a few peculiarities.
-Things don't appear to add up for a variety of reasons, most notably
-fragmentation losses.  These are probably much more significant for the
-contrived program "test.c" than for your application.)
-
-  Note that typing "make test" will automatically build the collector
-and then run setjmp_test and gctest. Setjmp_test will give you information
-about configuring the collector, which is useful primarily if you have
-a machine that's not already supported.  Gctest is a somewhat superficial
-test of collector functionality.  Failure is indicated by a core dump or
-a message to the effect that the collector is broken.  Gctest takes about 
-35 seconds to run on a SPARCstation 2. It may use up to 8 MB of memory.  (The
-multi-threaded version will use more.  64-bit versions may use more.)
-"Make test" will also, as its last step, attempt to build and test the
-"cord" string library.  This will fail without an ANSI C compiler, but
-the garbage collector itself should still be usable.
-
-  The Makefile will generate a library gc.a which you should link against.
-Typing "make cords" will add the cord library to gc.a.
-Note that this requires an ANSI C compiler.
-
-  It is suggested that if you need to replace a piece of the collector
-(e.g. GC_mark_rts.c) you simply list your version ahead of gc.a on the
-ld command line, rather than replacing the one in gc.a.  (This will
-generate numerous warnings under some versions of AIX, but it still
-works.)
-
-  All include files that need to be used by clients will be put in the
-include subdirectory.  (Normally this is just gc.h.  "Make cords" adds
-"cord.h" and "ec.h".)
-
-  The collector currently is designed to run essentially unmodified on
-machines that use a flat 32-bit or 64-bit address space.
-That includes the vast majority of Workstations and X86 (X >= 3) PCs.
-(The list here was deleted because it was getting too long and constantly
-out of date.)
-  It does NOT run under plain 16-bit DOS or Windows 3.X.  There are however
-various packages (e.g. win32s, djgpp) that allow flat 32-bit address
-applications to run under those systemsif the have at least an 80386 processor,
-and several of those are compatible with the collector.
-
-  In a few cases (Amiga, OS/2, Win32, MacOS) a separate makefile
-or equivalent is supplied.  Many of these have separate README.system
-files.
-
-  Dynamic libraries are completely supported only under SunOS
-(and even that support is not functional on the last Sun 3 release),
-Linux, IRIX 5&6, HP-PA, Win32 (not Win32S) and OSF/1 on DEC AXP machines.
-On other machines we recommend that you do one of the following:
-
-  1) Add dynamic library support (and send us the code).
-  2) Use static versions of the libraries.
-  3) Arrange for dynamic libraries to use the standard malloc.
-     This is still dangerous if the library stores a pointer to a
-     garbage collected object.  But nearly all standard interfaces
-     prohibit this, because they deal correctly with pointers
-     to stack allocated objects.  (Strtok is an exception.  Don't
-     use it.)
-
-  In all cases we assume that pointer alignment is consistent with that
-enforced by the standard C compilers.  If you use a nonstandard compiler
-you may have to adjust the alignment parameters defined in gc_priv.h.
-
-  A port to a machine that is not byte addressed, or does not use 32 bit
-or 64 bit addresses will require a major effort.  A port to plain MSDOS
-or win16 is hard.
-
-  For machines not already mentioned, or for nonstandard compilers, the
-following are likely to require change:
-
-1.  The parameters in gcconfig.h.
-      The parameters that will usually require adjustment are
-   STACKBOTTOM,  ALIGNMENT and DATASTART.  Setjmp_test
-   prints its guesses of the first two.
-      DATASTART should be an expression for computing the
-   address of the beginning of the data segment.  This can often be
-   &etext.  But some memory management units require that there be
-   some unmapped space between the text and the data segment.  Thus
-   it may be more complicated.   On UNIX systems, this is rarely
-   documented.  But the adb "$m" command may be helpful.  (Note
-   that DATASTART will usually be a function of &etext.  Thus a
-   single experiment is usually insufficient.)
-     STACKBOTTOM is used to initialize GC_stackbottom, which
-   should be a sufficient approximation to the coldest stack address.
-   On some machines, it is difficult to obtain such a value that is
-   valid across a variety of MMUs, OS releases, etc.  A number of
-   alternatives exist for using the collector in spite of this.  See the
-   discussion in gcconfig.h immediately preceding the various
-   definitions of STACKBOTTOM.
-   
-2.  mach_dep.c.
-      The most important routine here is one to mark from registers.
-    The distributed file includes a generic hack (based on setjmp) that
-    happens to work on many machines, and may work on yours.  Try
-    compiling and running setjmp_t.c to see whether it has a chance of
-    working.  (This is not correct C, so don't blame your compiler if it
-    doesn't work.  Based on limited experience, register window machines
-    are likely to cause trouble.  If your version of setjmp claims that
-    all accessible variables, including registers, have the value they
-    had at the time of the longjmp, it also will not work.  Vanilla 4.2 BSD
-    on Vaxen makes such a claim.  SunOS does not.)
-      If your compiler does not allow in-line assembly code, or if you prefer
-    not to use such a facility, mach_dep.c may be replaced by a .s file
-    (as we did for the MIPS machine and the PC/RT).
-      At this point enough architectures are supported by mach_dep.c
-    that you will rarely need to do more than adjust for assembler
-    syntax.
-
-3.  os_dep.c (and gc_priv.h).
-  	  Several kinds of operating system dependent routines reside here.
-  	Many are optional.  Several are invoked only through corresponding
-  	macros in gc_priv.h, which may also be redefined as appropriate.
-      The routine GC_register_data_segments is crucial.  It registers static
-    data areas that must be traversed by the collector. (User calls to
-    GC_add_roots may sometimes be used for similar effect.)
-      Routines to obtain memory from the OS also reside here.
-    Alternatively this can be done entirely by the macro GET_MEM
-    defined in gc_priv.h.  Routines to disable and reenable signals
-    also reside here if they are need by the macros DISABLE_SIGNALS
-    and ENABLE_SIGNALS defined in gc_priv.h.
-      In a multithreaded environment, the macros LOCK and UNLOCK
-    in gc_priv.h will need to be suitably redefined.
-      The incremental collector requires page dirty information, which
-    is acquired through routines defined in os_dep.c.  Unless directed
-    otherwise by gcconfig.h, these are implemented as stubs that simply
-    treat all pages as dirty.  (This of course makes the incremental
-    collector much less useful.)
-
-4.  dyn_load.c
-	This provides a routine that allows the collector to scan data
-	segments associated with dynamic libraries.  Often it is not
-	necessary to provide this routine unless user-written dynamic
-	libraries are used.
-
-  For a different version of UN*X or different machines using the
-Motorola 68000, Vax, SPARC, 80386, NS 32000, PC/RT, or MIPS architecture,
-it should frequently suffice to change definitions in gcconfig.h.
-
-
-THE C INTERFACE TO THE ALLOCATOR
-
-  The following routines are intended to be directly called by the user.
-Note that usually only GC_malloc is necessary.  GC_clear_roots and GC_add_roots
-calls may be required if the collector has to trace from nonstandard places
-(e.g. from dynamic library data areas on a machine on which the 
-collector doesn't already understand them.)  On some machines, it may
-be desirable to set GC_stacktop to a good approximation of the stack base. 
-(This enhances code portability on HP PA machines, since there is no
-good way for the collector to compute this value.)  Client code may include
-"gc.h", which defines all of the following, plus many others.
-
-1)  GC_malloc(nbytes)
-    - allocate an object of size nbytes.  Unlike malloc, the object is
-      cleared before being returned to the user.  Gc_malloc will
-      invoke the garbage collector when it determines this to be appropriate.
-      GC_malloc may return 0 if it is unable to acquire sufficient
-      space from the operating system.  This is the most probable
-      consequence of running out of space.  Other possible consequences
-      are that a function call will fail due to lack of stack space,
-      or that the collector will fail in other ways because it cannot
-      maintain its internal data structures, or that a crucial system
-      process will fail and take down the machine.  Most of these
-      possibilities are independent of the malloc implementation.
-
-2)  GC_malloc_atomic(nbytes)
-    - allocate an object of size nbytes that is guaranteed not to contain any
-      pointers.  The returned object is not guaranteed to be cleared.
-      (Can always be replaced by GC_malloc, but results in faster collection
-      times.  The collector will probably run faster if large character
-      arrays, etc. are allocated with GC_malloc_atomic than if they are
-      statically allocated.)
-
-3)  GC_realloc(object, new_size)
-    - change the size of object to be new_size.  Returns a pointer to the
-      new object, which may, or may not, be the same as the pointer to
-      the old object.  The new object is taken to be atomic iff the old one
-      was.  If the new object is composite and larger than the original object,
-      then the newly added bytes are cleared (we hope).  This is very likely
-      to allocate a new object, unless MERGE_SIZES is defined in gc_priv.h.
-      Even then, it is likely to recycle the old object only if the object
-      is grown in small additive increments (which, we claim, is generally bad
-      coding practice.)
-
-4)  GC_free(object)
-    - explicitly deallocate an object returned by GC_malloc or
-      GC_malloc_atomic.  Not necessary, but can be used to minimize
-      collections if performance is critical.  Probably a performance
-      loss for very small objects (<= 8 bytes).
-
-5)  GC_expand_hp(bytes)
-    - Explicitly increase the heap size.  (This is normally done automatically
-      if a garbage collection failed to GC_reclaim enough memory.  Explicit
-      calls to GC_expand_hp may prevent unnecessarily frequent collections at
-      program startup.)
-
-6)  GC_malloc_ignore_off_page(bytes)
-	- identical to GC_malloc, but the client promises to keep a pointer to
-	  the somewhere within the first 256 bytes of the object while it is
-	  live.  (This pointer should nortmally be declared volatile to prevent
-	  interference from compiler optimizations.)  This is the recommended
-	  way to allocate anything that is likely to be larger than 100Kbytes
-	  or so.  (GC_malloc may result in failure to reclaim such objects.)
-
-7)  GC_set_warn_proc(proc)
-	- Can be used to redirect warnings from the collector.  Such warnings
-	  should be rare, and should not be ignored during code development.
-      
-8) GC_enable_incremental()
-    - Enables generational and incremental collection.  Useful for large
-      heaps on machines that provide access to page dirty information.
-      Some dirty bit implementations may interfere with debugging
-      (by catching address faults) and place restrictions on heap arguments
-      to system calls (since write faults inside a system call may not be
-      handled well).
-
-9) Several routines to allow for registration of finalization code.
-   User supplied finalization code may be invoked when an object becomes
-   unreachable.  To call (*f)(obj, x) when obj becomes inaccessible, use
-	GC_register_finalizer(obj, f, x, 0, 0);
-   For more sophisticated uses, and for finalization ordering issues,
-   see gc.h.
-
-  The global variable GC_free_space_divisor may be adjusted up from its
-default value of 4 to use less space and more collection time, or down for
-the opposite effect.  Setting it to 1 or 0 will effectively disable collections
-and cause all allocations to simply grow the heap.
-
-  The variable GC_non_gc_bytes, which is normally 0, may be changed to reflect
-the amount of memory allocated by the above routines that should not be
-considered as a candidate for collection.  Careless use may, of course, result
-in excessive memory consumption.
-
-  Some additional tuning is possible through the parameters defined
-near the top of gc_priv.h.
-  
-  If only GC_malloc is intended to be used, it might be appropriate to define:
-
-#define malloc(n) GC_malloc(n)
-#define calloc(m,n) GC_malloc((m)*(n))
-
-  For small pieces of VERY allocation intensive code, gc_inl.h
-includes some allocation macros that may be used in place of GC_malloc
-and friends.
-
-  All externally visible names in the garbage collector start with "GC_".
-To avoid name conflicts, client code should avoid this prefix, except when
-accessing garbage collector routines or variables.
-
-  There are provisions for allocation with explicit type information.
-This is rarely necessary.  Details can be found in gc_typed.h.
-
-THE C++ INTERFACE TO THE ALLOCATOR:
-
-  The Ellis-Hull C++ interface to the collector is included in
-the collector distribution.  If you intend to use this, type
-"make c++" after the initial build of the collector is complete.
-See gc_cpp.h for the definition of the interface.  This interface
-tries to approximate the Ellis-Detlefs C++ garbage collection
-proposal without compiler changes.
-
-Cautions:
-1. Arrays allocated without new placement syntax are
-allocated as uncollectable objects.  They are traced by the
-collector, but will not be reclaimed.
-
-2. Failure to use "make c++" in combination with (1) will
-result in arrays allocated using the default new operator.
-This is likely to result in disaster without linker warnings.
-
-3. If your compiler supports an overloaded new[] operator,
-then gc_cpp.cc and gc_cpp.h should be suitably modified.
-
-4. Many current C++ compilers have deficiencies that
-break some of the functionality.  See the comments in gc_cpp.h
-for suggested workarounds.
-
-USE AS LEAK DETECTOR:
-
-  The collector may be used to track down leaks in C programs that are
-intended to run with malloc/free (e.g. code with extreme real-time or
-portability constraints).  To do so define FIND_LEAK in Makefile
-This will cause the collector to invoke the report_leak
-routine defined near the top of reclaim.c whenever an inaccessible
-object is found that has not been explicitly freed.  Such objects will
-also be automatically reclaimed.
-  Productive use of this facility normally involves redefining report_leak
-to do something more intelligent.  This typically requires annotating
-objects with additional information (e.g. creation time stack trace) that
-identifies their origin.  Such code is typically not very portable, and is
-not included here, except on SPARC machines.
-  If all objects are allocated with GC_DEBUG_MALLOC (see next section),
-then the default version of report_leak will report the source file
-and line number at which the leaked object was allocated.  This may
-sometimes be sufficient.  (On SPARC/SUNOS4 machines, it will also report
-a cryptic stack trace.  This can often be turned into a sympolic stack
-trace by invoking program "foo" with "callprocs foo".  Callprocs is
-a short shell script that invokes adb to expand program counter values
-to symbolic addresses.  It was largely supplied by Scott Schwartz.)
-  Note that the debugging facilities described in the next section can
-sometimes be slightly LESS effective in leak finding mode, since in
-leak finding mode, GC_debug_free actually results in reuse of the object.
-(Otherwise the object is simply marked invalid.)  Also note that the test
-program is not designed to run meaningfully in FIND_LEAK mode.
-Use "make gc.a" to build the collector.
-
-DEBUGGING FACILITIES:
-
-  The routines GC_debug_malloc, GC_debug_malloc_atomic, GC_debug_realloc,
-and GC_debug_free provide an alternate interface to the collector, which
-provides some help with memory overwrite errors, and the like.
-Objects allocated in this way are annotated with additional
-information.  Some of this information is checked during garbage
-collections, and detected inconsistencies are reported to stderr.
-
-  Simple cases of writing past the end of an allocated object should
-be caught if the object is explicitly deallocated, or if the
-collector is invoked while the object is live.  The first deallocation
-of an object will clear the debugging info associated with an
-object, so accidentally repeated calls to GC_debug_free will report the
-deallocation of an object without debugging information.  Out of
-memory errors will be reported to stderr, in addition to returning
-NIL.
-
-  GC_debug_malloc checking  during garbage collection is enabled
-with the first call to GC_debug_malloc.  This will result in some
-slowdown during collections.  If frequent heap checks are desired,
-this can be achieved by explicitly invoking GC_gcollect, e.g. from
-the debugger.
-
-  GC_debug_malloc allocated objects should not be passed to GC_realloc
-or GC_free, and conversely.  It is however acceptable to allocate only
-some objects with GC_debug_malloc, and to use GC_malloc for other objects,
-provided the two pools are kept distinct.  In this case, there is a very
-low probablility that GC_malloc allocated objects may be misidentified as
-having been overwritten.  This should happen with probability at most
-one in 2**32.  This probability is zero if GC_debug_malloc is never called.
-
-  GC_debug_malloc, GC_malloc_atomic, and GC_debug_realloc take two
-additional trailing arguments, a string and an integer.  These are not
-interpreted by the allocator.  They are stored in the object (the string is
-not copied).  If an error involving the object is detected, they are printed.
-
-  The macros GC_MALLOC, GC_MALLOC_ATOMIC, GC_REALLOC, GC_FREE, and
-GC_REGISTER_FINALIZER are also provided.  These require the same arguments
-as the corresponding (nondebugging) routines.  If gc.h is included
-with GC_DEBUG defined, they call the debugging versions of these
-functions, passing the current file name and line number as the two
-extra arguments, where appropriate.  If gc.h is included without GC_DEBUG
-defined, then all these macros will instead be defined to their nondebugging
-equivalents.  (GC_REGISTER_FINALIZER is necessary, since pointers to
-objects with debugging information are really pointers to a displacement
-of 16 bytes form the object beginning, and some translation is necessary
-when finalization routines are invoked.  For details, about what's stored
-in the header, see the definition of the type oh in debug_malloc.c)
-
-INCREMENTAL/GENERATIONAL COLLECTION:
-
-The collector normally interrupts client code for the duration of 
-a garbage collection mark phase.  This may be unacceptable if interactive
-response is needed for programs with large heaps.  The collector
-can also run in a "generational" mode, in which it usually attempts to
-collect only objects allocated since the last garbage collection.
-Furthermore, in this mode, garbage collections run mostly incrementally,
-with a small amount of work performed in response to each of a large number of
-GC_malloc requests.
-
-This mode is enabled by a call to GC_enable_incremental().
-
-Incremental and generational collection is effective in reducing
-pause times only if the collector has some way to tell which objects
-or pages have been recently modified.  The collector uses two sources
-of information:
-
-1. Information provided by the VM system.  This may be provided in
-one of several forms.  Under Solaris 2.X (and potentially under other
-similar systems) information on dirty pages can be read from the
-/proc file system.  Under other systems (currently SunOS4.X) it is
-possible to write-protect the heap, and catch the resulting faults.
-On these systems we require that system calls writing to the heap
-(other than read) be handled specially by client code.
-See os_dep.c for details.
-
-2. Information supplied by the programmer.  We define "stubborn"
-objects to be objects that are rarely changed.  Such an object
-can be allocated (and enabled for writing) with GC_malloc_stubborn.
-Once it has been initialized, the collector should be informed with
-a call to GC_end_stubborn_change.  Subsequent writes that store
-pointers into the object must be preceded by a call to
-GC_change_stubborn.
-
-This mechanism performs best for objects that are written only for
-initialization, and such that only one stubborn object is writable
-at once.  It is typically not worth using for short-lived
-objects.  Stubborn objects are treated less efficiently than pointerfree
-(atomic) objects.
-
-A rough rule of thumb is that, in the absence of VM information, garbage
-collection pauses are proportional to the amount of pointerful storage
-plus the amount of modified "stubborn" storage that is reachable during
-the collection.  
-
-Initial allocation of stubborn objects takes longer than allocation
-of other objects, since other data structures need to be maintained.
-
-We recommend against random use of stubborn objects in client
-code, since bugs caused by inappropriate writes to stubborn objects
-are likely to be very infrequently observed and hard to trace.  
-However, their use may be appropriate in a few carefully written
-library routines that do not make the objects themselves available
-for writing by client code.
-
-
-BUGS:
-
-  Any memory that does not have a recognizable pointer to it will be
-reclaimed.  Exclusive-or'ing forward and backward links in a list
-doesn't cut it.
-  Some C optimizers may lose the last undisguised pointer to a memory
-object as a consequence of clever optimizations.  This has almost
-never been observed in practice.  Send mail to boehm@acm.org
-for suggestions on how to fix your compiler.
-  This is not a real-time collector.  In the standard configuration,
-percentage of time required for collection should be constant across
-heap sizes.  But collection pauses will increase for larger heaps.
-(On SPARCstation 2s collection times will be on the order of 300 msecs
-per MB of accessible memory that needs to be scanned.  Your mileage
-may vary.)  The incremental/generational collection facility helps,
-but is portable only if "stubborn" allocation is used.
-  Please address bug reports to boehm@acm.org.  If you are
-contemplating a major addition, you might also send mail to ask whether
-it's already been done (or whether we tried and discarded it).
-
diff --git a/gc/doc/README.DGUX386 b/gc/doc/README.DGUX386
deleted file mode 100644
index 9d6d847..0000000
--- a/gc/doc/README.DGUX386
+++ /dev/null
@@ -1,215 +0,0 @@
-    Garbage Collector (parallel iversion) for ix86 DG/UX Release R4.20MU07
-
-
-     *READ* the file README.QUICK.
-
-     You need the GCC-3.0.3 rev (DG/UX) compiler to build this tree.
-     This compiler has the new "dgux386" threads package implemented.
-     It also supports the switch "-pthread" needed to link correctly
-     the DG/UX's -lrte -lthread with -lgcc and the system's -lc. 
-     Finally we support parralleli-mark for the SMP DG/UX machines.
-     To build the garbage collector do:
-      
-      ./configure --enable-parallel-mark
-      make
-      make gctest
-
-     Before you run "gctest" you need to set your LD_LIBRARY_PATH
-     correctly so that "gctest" can find the shared library libgc.
-     Alternatively you can do a configuration
-
-      ./configure --enable-parallel-mark --disable-shared
-  
-     to build only the static version of libgc.
-  
-     To enable debugging messages please do:
-     1) Add the "--enable-full-debug" flag during configuration. 
-     2) Edit the file linux-threads.c and uncommnect the line:
-
-     /* #define DEBUG_THREADS 1 */ to ---> 
-
-     #define DEBUG_THREADS 1
-
-     Then give "make" as usual.
-    
-     In a machine with 4 CPUs (my own machine) the option parallel
-     mark (aka --enable-parallel-mark) makes a BIG difference.
-
-     Takis Psarogiannakopoulos
-     University of Cambridge
-     Centre for Mathematical Sciences
-     Department of Pure Mathematics
-     Wilberforce Road
-     Cambridge CB3 0WB ,UK , <takis@XFree86.Org>
-     January 2002
-
-
-Note (HB):
-     The integration of this patch is currently not complete.
-     The following patches against 6.1alpha3 where hard to move
-     to alpha4, and are not integrated.  There may also be minor
-     problems with stylistic corrections made by me.
-
-
---- ltconfig.ORIG	Mon Jan 28 20:22:18 2002
-+++ ltconfig	Mon Jan 28 20:44:00 2002
-@@ -689,6 +689,11 @@
-        pic_flag=-Kconform_pic
-     fi
-     ;;
-+  dgux*)
-+    pic_flag='-fPIC'
-+    link_static='-Bstatic'
-+    wl='-Wl,'
-+    ;;
-   *)
-     pic_flag='-fPIC'
-     ;;
-@@ -718,6 +723,12 @@
-     # We can build DLLs from non-PIC.
-     ;;
- 
-+  dgux*)
-+    pic_flag='-KPIC'
-+    link_static='-Bstatic'
-+    wl='-Wl,'
-+    ;;
-+
-   osf3* | osf4* | osf5*)
-     # All OSF/1 code is PIC.
-     wl='-Wl,'
-@@ -1154,6 +1165,22 @@
-     fi
-     ;;
- 
-+  dgux*)
-+    ld_shlibs=yes
-+    # For both C/C++ ommit the deplibs. This is because we relying on the fact
-+    # that compilation of execitables will put them in correct order
-+    # in any case and sometimes are wrong when listed as deplibs (or missing some deplibs)
-+    # However when GNU ld and --whole-archive needs to be used we have the problem
-+    # that if the -fPIC *_s.a archive is linked through deplibs list we ommiting crucial
-+    # .lo/.o files from the created shared lib. This I think is not the case here.
-+    archive_cmds='$CC -shared -h $soname -o $lib $libobjs $linkopts'
-+    thread_safe_flag_spec='-pthread'
-+    wlarc=
-+    hardcode_libdir_flag_spec='-L$libdir'
-+    hardcode_shlibpath_var=no
-+    ac_cv_archive_cmds_needs_lc=no
-+    ;;
-+
-   cygwin* | mingw*)
-     # hardcode_libdir_flag_spec is actually meaningless, as there is
-     # no search path for DLLs.
-@@ -1497,7 +1524,7 @@
-     ;;
- 
-   dgux*)
--    archive_cmds='$LD -G -h $soname -o $lib $libobjs $deplibs $linkopts'
-+    archive_cmds='$CC -shared -h $soname -o $lib $libobjs $linkopts'
-     hardcode_libdir_flag_spec='-L$libdir'
-     hardcode_shlibpath_var=no
-     ;;
-@@ -2092,12 +2119,17 @@
-   ;;
- 
- dgux*)
--  version_type=linux
-+  version_type=dgux
-   need_lib_prefix=no
-   need_version=no
--  library_names_spec='${libname}${release}.so$versuffix ${libname}${release}.so$major $libname.so'
--  soname_spec='${libname}${release}.so$major'
-+  library_names_spec='$libname.so$versuffix'
-+  soname_spec='$libname.so$versuffix'
-   shlibpath_var=LD_LIBRARY_PATH
-+  thread_safe_flag_spec='-pthread'
-+  wlarc=
-+  hardcode_libdir_flag_spec='-L$libdir'
-+  hardcode_shlibpath_var=no
-+  ac_cv_archive_cmds_needs_lc=no
-   ;;
- 
- sysv4*MP*)
-
-
---- ltmain.sh.ORIG	Mon Jan 28 20:31:18 2002
-+++ ltmain.sh	Tue Jan 29 00:11:29 2002
-@@ -1072,11 +1072,38 @@
- 	esac
- 	;;
- 
-+      -thread*)
-+	# DG/UX GCC 2.95.x, 3.x.x rev (DG/UX) links -lthread
-+	# with the switch -threads
-+	if test "$arg" = "-threads"; then
-+	  case "$host" in
-+	  i[3456]86-*-dgux*)
-+	    deplibs="$deplibs $arg"
-+	    continue
-+	    ;;
-+	  esac
-+	fi
-+	;;
-+
-+      -pthread*)
-+	# DG/UX GCC 2.95.x, 3.x.x rev (DG/UX) links -lthread
-+	# with the switch -pthread
-+	if test "$arg" = "-pthread"; then
-+	  case "$host" in
-+	  i[3456]86-*-dgux*)
-+	    deplibs="$deplibs $arg"
-+	    continue
-+	    ;;
-+	  esac
-+	fi
-+	;;
-+
-       -l*)
- 	if test "$arg" = "-lc"; then
- 	  case "$host" in
--	  *-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos*)
-+	  *-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos* | i[3456]86-*-dgux*)
- 	    # These systems don't actually have c library (as such)
-+	    # It is wrong in DG/UX to add -lc when creating shared/dynamic objs/libs
- 	    continue
- 	    ;;
- 	  esac
-@@ -1248,6 +1275,12 @@
- 	  temp_deplibs=
- 	  for deplib in $dependency_libs; do
- 	    case "$deplib" in
-+	    -thread*)
-+		 temp_deplibs="$temp_deplibs $deplib"
-+		 ;;
-+	    -pthread)
-+		 temp_deplibs="$temp_deplibs $deplib"
-+		 ;;
- 	    -R*) temp_xrpath=`$echo "X$deplib" | $Xsed -e 's/^-R//'`
- 		 case " $rpath $xrpath " in
- 		 *" $temp_xrpath "*) ;;
-@@ -1709,6 +1742,13 @@
- 	  done
- 	  ;;
- 
-+	dgux)
-+	  # Leave mostly blank for DG/UX
-+	  major=
-+	  versuffix=".$current.$revision";
-+	  verstring=
-+	  ;;
-+
- 	linux)
- 	  major=.`expr $current - $age`
- 	  versuffix="$major.$age.$revision"
-@@ -1792,8 +1832,9 @@
- 
- 	dependency_libs="$deplibs"
- 	case "$host" in
--	*-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos*)
-+	*-*-cygwin* | *-*-mingw* | *-*-os2* | *-*-beos* | i[3456]86-*-dgux*)
- 	  # these systems don't actually have a c library (as such)!
-+	  # It is wrong in DG/UX to add -lc when creating shared/dynamic objs/libs
- 	  ;;
- 	*)
- 	  # Add libc to deplibs on all other systems.
diff --git a/gc/doc/README.Mac b/gc/doc/README.Mac
deleted file mode 100644
index 04f4682..0000000
--- a/gc/doc/README.Mac
+++ /dev/null
@@ -1,385 +0,0 @@
-Patrick Beard's Notes for building GC v4.12 with CodeWarrior Pro 2:
-----------------------------------------------------------------------------
-The current build environment for the collector is CodeWarrior Pro 2.
-Projects for CodeWarrior Pro 2 (and for quite a few older versions)
-are distributed in the file Mac_projects.sit.hqx. The project file
-:Mac_projects:gc.prj builds static library versions of the collector.
-:Mac_projects:gctest.prj builds the GC test suite.
-
-Configuring the collector is still done by editing the files
-:Mac_files:MacOS_config.h and :Mac_files:MacOS_Test_config.h.
-
-Lars Farm's suggestions on building the collector:
-----------------------------------------------------------------------------
-Garbage Collection on MacOS - a manual 'MakeFile'
--------------------------------------------------
-
-Project files and IDE's are great on the Macintosh, but they do have
-problems when used as distribution media. This note tries to provide
-porting instructions in pure TEXT form to avoid those problems. A manual
-'makefile' if you like.
-
-    GC version:     4.12a2
-    Codewarrior:    CWPro1
-    date:           18 July 1997
-
-The notes may or may not apply to earlier or later versions of the
-GC/CWPro. Actually, they do apply to earlier versions of both except that
-until recently a project could only build one target so each target was a
-separate project. The notes will most likely apply to future versions too.
-Possibly with minor tweaks.
-
-This is just to record my experiences. These notes do not mean I now
-provide a supported port of the GC to MacOS. It works for me. If it works
-for you, great. If it doesn't, sorry, try again...;-) Still, if you find
-errors, please let me know.
-
-    mailto:         lars.farm@ite.mh.se
-
-    address:        Lars Farm
-                    Krönvägen 33b
-                    856 44 Sundsvall
-                    Sweden
-
-Porting to MacOS is a bit more complex than it first seems. Which MacOS?
-68K/PowerPC? Which compiler? Each supports both 68K and PowerPC and offer a
-large number of (unique to each environment) compiler settings. Each
-combination of compiler/68K/PPC/settings require a unique combination of
-standard libraries. And the IDE's does not select them for you. They don't
-even check that the library is built with compatible setting and this is
-the major source of problems when porting the GC (and otherwise too).
-
-You will have to make choices when you configure the GC. I've made some
-choices here, but there are other combinations of settings and #defines
-that work too.
-
-As for target settings the major obstacles may be:
-- 68K Processor: check "4-byte Ints".
-- PPC Processor: uncheck "Store Static Data in TOC".
-
-What you need to do:
-===================
-
-1) Build the GC as a library
-2) Test that the library works with 'test.c'.
-3) Test that the C++ interface 'gc_cpp.cc/h' works with 'test_cpp.cc'.
-
-1) The Libraries:
-=================
-I made one project with four targets (68K/PPC tempmem or appheap). One target
-will suffice if you're able to decide which one you want. I wasn't...
-
-Codewarrior allows a large number of compiler/linker settings. I used these:
-
-Settings shared by all targets:
-------------------------------
-o Access Paths:
-  - User Paths:   the GC folder
-  - System Paths: {Compiler}:Metrowerks Standard Library:
-                  {Compiler}:MacOS Support:Headers:
-                  {Compiler}:MacOS Support:MacHeaders:
-o C/C++ language:
-  - inlining: normal
-  - direct to SOM: off
-  - enable/check: exceptions, RTTI, bool (and if you like pool strings)
-
-PowerPC target settings
------------------------
-o Target Settings:
-  - name of target
-  - MacOS PPC Linker
-o PPC Target
-  - name of library
-o C/C++ language
-  - prefix file as described below
-o PPC Processor
-  - Struct Alignment: PowerPC
-  - uncheck "Store Static Data in TOC" -- important!
-    I don't think the others matter, I use full optimization and its ok
-o PPC Linker
-  - Factory Settings (SYM file with full paths, faster linking, dead-strip
-    static init, Main: __start)
-
-
-68K target settings
--------------------
-o Target Settings:
-  - name of target
-  - MacOS 68K Linker
-o 68K Target
-  - name of library
-  - A5 relative data
-o C/C++ language
-  - prefix file as described below
-o 68K Processor
-  - Code model: smart
-  - Struct alignment: 68K
-  - FP: SANE
-  - enable 4-Byte Ints -- important!
-    I don't think the others matter. I selected...
-  - enable: 68020
-  - enable: global register allocation
-o IR Optimizer
-  - enable: Optimize Space, Optimize Speed
-    I suppose the others would work too, but haven't tried...
-o 68K Linker
-  - Factory Settings (New Style MacsBug,SYM file with full paths,
-    A6 Frames, fast link, Merge compiler glue into segment 1,
-    dead-strip static init)
-
-Prefix Files to configure the GC sources
-----------------------------------------
-The Codewarrior equivalent of commandline compilers -DNAME=X is to use
-prefix-files. A TEXT file that is automatically #included before the first byte
-of every source file. I used these:
-
----- ( cut here ) ----  gc_prefix_tempmem.h     -- 68K and PPC -----
-    #include "gc_prefix_common.h"
-    #undef USE_TEMPORARY_MEMORY
-    #define USE_TEMPORARY_MEMORY
----- ( cut here ) ----  gc_prefix_appmem.h      -- 68K and PPC -----
-    #include "gc_prefix_common.h"
-    #undef USE_TEMPORARY_MEMORY
-//  #define USE_TEMPORARY_MEMORY
-
----- ( cut here ) ----  gc_prefix_common.h      --------------------
-// gc_prefix_common.h
-// ------------------
-// Codewarrior prefix file to configure the GC libraries
-//
-//   prefix files are the Codewarrior equivalent of the
-//   command line option -Dname=x frequently seen in makefiles
-
-#if !__MWERKS__
-  #error only tried this with Codewarrior
-#endif
-
-#if macintosh
-  #define MSL_USE_PRECOMPILED_HEADERS 0
-  #include <ansi_prefix.mac.h>
-  #ifndef __STDC__
-    #define __STDC__ 0
-  #endif
-
-  //  See list of #defines to configure the library in: 'MakeFile'
-  //  see also README
-
-  #define SILENT                // no collection messages. In case
-                                // of trouble you might want this off
-  #define ALL_INTERIOR_POINTERS // follows interior pointers.
-//#define DONT_ADD_BYTE_AT_END  // disables the padding if defined.
-//#define SMALL_CONFIG          // whether to use a smaller heap.
-  #define NO_SIGNALS            // signals aren't real on the Macintosh.
-  #define ATOMIC_UNCOLLECTABLE  // GC_malloc_atomic_uncollectable()
-
-  // define either or none as per personal preference
-  //   used in malloc.c
-  #define REDIRECT_MALLOC GC_malloc
-//#define REDIRECT_MALLOC GC_malloc_uncollectable
-  // if REDIRECT_MALLOC is #defined make sure that the GC library
-  // is listed before the ANSI/ISO libs in the Codewarrior
-  // 'Link order' panel
-//#define IGNORE_FREE
-
-  // mac specific configs
-//#define USE_TEMPORARY_MEMORY    // use Macintosh temporary memory.
-//#define SHARED_LIBRARY_BUILD    // build for use in a shared library.
-
-#else
-  // could build Win32 here too, or in the future
-  // Rhapsody PPC-mach, Rhapsody PPC-MacOS,
-  // Rhapsody Intel-mach, Rhapsody Intel-Win32,...
-  // ... ugh this will get messy ...
-#endif
-
-// make sure ints are at least 32-bit
-// ( could be set to 16-bit by compiler settings (68K) )
-
-struct gc_private_assert_intsize_{ char x[ sizeof(int)>=4 ? 1 : 0 ]; };
-
-#if __powerc
-  #if __option(toc_data)
-    #error turn off "store static data in TOC" when using GC
-    //     ... or find a way to add TOC to the root set...(?)
-  #endif
-#endif
----- ( cut here ) ----  end of gc_prefix_common.h  -----------------
-
-Files to  build the GC libraries:
---------------------------------
-    allchblk.c
-    alloc.c
-    blacklst.c
-    checksums.c
-    dbg_mlc.c
-    finalize.c
-    headers.c
-    mach_dep.c
-    MacOS.c    -- contains MacOS code
-    malloc.c
-    mallocx.c
-    mark.c
-    mark_rts.c
-    misc.c
-    new_hblk.c
-    obj_map.c
-    os_dep.c   -- contains MacOS code
-    ptr_chck.c
-    reclaim.c
-    stubborn.c
-    typd_mlc.c
-    gc++.cc    -- this is 'gc_cpp.cc' with less 'inline' and
-               -- throw std::bad_alloc when out of memory
-               -- gc_cpp.cc works just fine too
-
-2) Test that the library works with 'test.c'.
-=============================================
-
-The test app is just an ordinary ANSI-C console app. Make sure settings
-match the library you're testing.
-
-Files
------
-    test.c
-    the GC library to test        -- link order before ANSI libs
-    suitable Mac+ANSI libraries
-
-prefix:
-------
----- ( cut here ) ----  gc_prefix_testlib.h     -- all libs -----
-#define MSL_USE_PRECOMPILED_HEADERS 0
-#include <ansi_prefix.mac.h>
-#undef NDEBUG
-
-#define ALL_INTERIOR_POINTERS	/* for GC_priv.h */
----- ( cut here ) ----
-
-3) Test that the C++ interface 'gc_cpp.cc/h' works with 'test_cpp.cc'.
-
-The test app is just an ordinary ANSI-C console app. Make sure settings match
-the library you're testing.
-
-Files
------
-    test_cpp.cc
-    the GC library to test        -- link order before ANSI libs
-    suitable Mac+ANSI libraries
-
-prefix:
-------
-same as for test.c
-
-For convenience I used one test-project with several targets so that all
-test apps are build at once. Two for each library to test: test.c and
-gc_app.cc. When I was satisfied that the libraries were ok. I put the
-libraries + gc.h + the c++ interface-file in a folder that I then put into
-the MSL hierarchy so that I don't have to alter access-paths in projects
-that use the GC.
-
-After that, just add the proper GC library to your project and the GC is in
-action! malloc will call GC_malloc and free GC_free, new/delete too. You
-don't have to call free or delete. You may have to be a bit cautious about
-delete if you're freeing other resources than RAM. See gc_cpp.h. You can
-also keep coding as always with delete/free. That works too. If you want,
-"include <gc.h> and tweak it's use a bit.
-
-Symantec SPM
-============
-It has been a while since I tried the GC in SPM, but I think that the above
-instructions should be sufficient to guide you through in SPM too. SPM
-needs to know where the global data is. Use the files 'datastart.c' and
-'dataend.c'. Put 'datastart.c' at the top of your project and 'dataend.c'
-at the bottom  of your project so that all data is surrounded. This is not
-needed in Codewarrior because it provides intrinsic variables
-__datastart__, __data_end__ that wraps all globals.
-
-Source Changes (GC 4.12a2)
-==========================
-Very few. Just one tiny in the GC, not strictly needed.
-- MacOS.c line 131 in routine GC_MacFreeTemporaryMemory()
-  change #       if !defined(SHARED_LIBRARY_BUILD)
-  to     #       if !defined(SILENT) && !defined(SHARED_LIBRARY_BUILD)
-  To turn off a message when the application quits (actually, I faked
-  this change by #defining SHARED_LIBRARY_BUILD in a statically linked
-  library for more than a year without ill effects but perhaps this is
-  better).
-
-- test_cpp.cc
-  made the first lines of main() look like this:
-  ------------
-  int main( int argc, char* argv[] ) {
-  #endif
-  #if macintosh                             // MacOS
-    char* argv_[] = {"test_cpp","10"};      //   doesn't
-    argv=argv_;                             //     have a
-    argc = sizeof(argv_)/sizeof(argv_[0]);  //       commandline
-  #endif                                    //
-
-  int i, iters, n;
-  # ifndef __GNUC__
-   alloc dummy_to_fool_the_compiler_into_doing_things_it_currently_cant_handle;
-  ------------
-
-- config.h [now gcconfig.h]
-  __MWERKS__ does not have to mean MACOS. You can use Codewarrior to
-  build a Win32 or BeOS library and soon a Rhapsody library. You may
-  have to change that #if...
-
-
-
-   It worked for me, hope it works for you.
-
-   Lars Farm
-   18 July 1997
-----------------------------------------------------------------------------
-
-
-Patrick Beard's instructions (may be dated):
-
-v4.3 of the collector now runs under Symantec C++/THINK C v7.0.4, and
-Metrowerks C/C++ v4.5 both 68K and PowerPC. Project files are provided
-to build and test the collector under both development systems.
-
-Configuration
--------------
-
-To configure the collector, under both development systems, a prefix file
-is used to set preprocessor directives. This file is called "MacOS_config.h".
-Also to test the collector, "MacOS_Test_config.h" is provided.
-
-Testing
--------
-
-To test the collector (always a good idea), build one of the gctest projects,
-gctest.¹ (Symantec C++/THINK C), mw/gctest.68K.¹, or mw/gctest.PPC.¹. The
-test will ask you how many times to run; 1 should be sufficient.
-
-Building 
---------
-
-For your convenience project files for the major Macintosh development
-systems are provided.
-
-For Symantec C++/THINK C, you must build the two projects gclib-1.¹ and
-gclib-2.¹. It has to be split up because the collector has more than 32k
-of static data and no library can have more than this in the Symantec
-environment. (Future versions will probably fix this.)
-
-For Metrowerks C/C++ 4.5 you build gc.68K.¹/gc.PPC.¹ and the result will
-be a library called gc.68K.lib/gc.PPC.lib.
-
-Using
------
-
-Under Symantec C++/THINK C, you can just add the gclib-1.¹ and gclib-2.¹
-projects to your own project. Under Metrowerks, you add gc.68K.lib or
-gc.PPC.lib and two additional files. You add the files called datastart.c
-and dataend.c to your project, bracketing all files that use the collector.
-See mw/gctest.¹ for an example.
-
-Include the projects/libraries you built above into your own project,
-#include "gc.h", and call GC_malloc. You don't have to call GC_free.
-
-
-Patrick C. Beard
-January 4, 1995
diff --git a/gc/doc/README.MacOSX b/gc/doc/README.MacOSX
deleted file mode 100644
index 2abf0b4..0000000
--- a/gc/doc/README.MacOSX
+++ /dev/null
@@ -1,27 +0,0 @@
-While the GC should work on MacOS X Server, MacOS X and Darwin, I only tested
-it on MacOS X Server.
-I've added a PPC assembly version of GC_push_regs(), thus the setjmp() hack is
-no longer necessary. Incremental collection is supported via mprotect/signal.
-The current solution isn't really optimal because the signal handler must decode
-the faulting PPC machine instruction in order to find the correct heap address.
-Further, it must poke around in the register state which the kernel saved away
-in some obscure register state structure before it calls the signal handler -
-needless to say the layout of this structure is no where documented.
-Threads and dynamic libraries are not yet supported (adding dynamic library
-support via the low-level dyld API shouldn't be that hard).
-
-The original MacOS X port was brought to you by Andrew Stone.
-
-
-June, 1 2000
-
-Dietmar Planitzer
-dave.pl@ping.at
-
-Note from Andrew Begel:
-
-One more fix to enable gc.a to link successfully into a shared library for
-MacOS X. You have to add -fno-common to the CFLAGS in the Makefile. MacOSX
-disallows common symbols in anything that eventually finds its way into a
-shared library. (I don't completely understand why, but -fno-common seems to
-work and doesn't mess up the garbage collector's functionality).
diff --git a/gc/doc/README.OS2 b/gc/doc/README.OS2
deleted file mode 100644
index 5345bbd..0000000
--- a/gc/doc/README.OS2
+++ /dev/null
@@ -1,6 +0,0 @@
-The code assumes static linking, and a single thread.  The editor de has
-not been ported.  The cord test program has.  The supplied OS2_MAKEFILE
-assumes the IBM C Set/2 environment, but the code shouldn't.
-
-Since we haven't figured out hoe to do perform partial links or to build static
-libraries, clients currently need to link against a long list of executables.
diff --git a/gc/doc/README.amiga b/gc/doc/README.amiga
deleted file mode 100644
index 730dce3..0000000
--- a/gc/doc/README.amiga
+++ /dev/null
@@ -1,322 +0,0 @@
-===========================================================================
-            Kjetil S. Matheussen's notes (28-11-2000)
-===========================================================================
-Compiles under SAS/C again. Should allso still compile under other
-amiga compilers without big changes. I haven't checked if it still
-works under gcc, because I don't have gcc for amiga. But I have
-updated 'Makefile', and hope it compiles fine.
-
-
-WHATS NEW:
-
-1.
-   Made a pretty big effort in preventing GCs allocating-functions from returning
-   chip-mem.
-
-   The lower part of the new file AmigaOS.c does this in various ways, mainly by
-   wrapping GC_malloc, GC_malloc_atomic, GC_malloc_uncollectable,
-   GC_malloc_atomic_uncollectable, GC_malloc_stubborn, GC_malloc_ignore_off_page
-   and GC_malloc_atomic_ignore_off_page. GC_realloc is allso wrapped, but
-   doesn't do the same effort in preventing to return chip-mem.
-   Other allocating-functions (f.ex. GC_*_typed_) can probably be
-   used without any problems, but beware that the warn hook will not be called.
-   In case of problems, don't define GC_AMIGA_FASTALLOC.
-
-   Programs using more time actually using the memory allocated
-   (instead of just allocate and free rapidly) have
-   the most to earn on this, but even gctest now normally runs twice
-   as fast and uses less memory, on my poor 8MB machine.
-
-   The changes have only effect when there is no more
-   fast-mem left. But with the way GC works, it
-   could happen quite often. Beware that an atexit handler had to be added,
-   so using the abort() function will make a big memory-loss.
-   If you absolutely must call abort() instead of exit(), try calling
-   the GC_amiga_free_all_mem function before abort().
-
-   New amiga-spesific compilation flags:
-
-   GC_AMIGA_FASTALLOC - By NOT defining this option, GC will work like before,
-                        it will not try to force fast-mem out of the OS, and
-                        it will use normal calloc for allocation, and the rest
-                        of the following flags will have no effect.
-
-   GC_AMIGA_ONLYFAST - Makes GC never to return chip-mem. GC_AMIGA_RETRY have
-                       no effect if this flag is set.
-
-   GC_AMIGA_GC - If gc returns NULL, do a GC_gcollect, and try again. This
-                 usually is a success with the standard GC configuration. 
-                 It is allso the most important flag to set to prevent
-                 GC from returning chip-mem. Beware that it slows down a lot
-                 when a program is rapidly allocating/deallocating when
-                 theres either very little fast-memory left or verly little
-                 chip-memory left. Its not a very common situation, but gctest
-                 sometimes (very rare) use many minutes because of this.
-
-   GC_AMIGA_RETRY - If gc succeed allocating memory, but it is chip-mem,
-                    try again and see if it is fast-mem. Most of the time,
-                    it will actually return fast-mem for the second try.
-                    I have set max number of retries to 9 or size/5000. You
-                    can change this if you like. (see GC_amiga_rec_alloc())
-
-   GC_AMIGA_PRINTSTATS - Gather some statistics during the execution of a
-                         program, and prints out the info when the atexit-handler
-                         is called.
-
-   My reccomendation is to set all this flags, except GC_AMIGA_PRINTSTATS and
-   GC_AMIGA_ONLYFAST.
-
-   If your program demands high response-time, you should
-   not define GC_AMIGA_GC, and possible allso define GC_AMIGA_ONLYFAST.
-   GC_AMIGA_RETRY does not seem to slow down much.
-
-   Allso, when compiling up programs, and GC_AMIGA_FASTALLOC was not defined when
-   compilling gc, you can define GC_AMIGA_MAKINGLIB to avoid having these allocation-
-   functions wrapped. (see gc.h)
-
-   Note that GC_realloc must not be called before any of
-   the other above mentioned allocating-functions have been called. (shouldn't be
-   any programs doing so either, I hope).
-
-   Another note. The allocation-function is wrapped when defining
-   GC_AMIGA_FASTALLOC by letting the function go thru the new
-   GC_amiga_allocwrapper_do function-pointer (see gc.h). Means that
-   sending function-pointers, such as GC_malloc, GC_malloc_atomic, etc.,
-   for later to be called like f.ex this, (*GC_malloc_functionpointer)(size),
-   will not wrap the function. This is normally not a big problem, unless
-   all allocation function is called like this, which will cause the
-   atexit un-allocating function never to be called. Then you either
-   have to manually add the atexit handler, or call the allocation-
-   functions function-pointer functions like this;
-   (*GC_amiga_allocwrapper_do)(size,GC_malloc_functionpointer).
-   There are probably better ways this problem could be handled, unfortunately,
-   I didn't find any without rewriting or replacing a lot of the GC-code, which
-   I really didn't want to. (Making new GC_malloc_* functions, and just
-   define f.ex GC_malloc as GC_amiga_malloc should allso work).
-
-
-   New amiga-spesific function:
-
-     void GC_amiga_set_toany(void (*func)(void));
-
-   'func' is a function that will be called right before gc has to change
-   allocation-method from MEMF_FAST to MEMF_ANY. Ie. when it is likely
-   it will return chip-mem.
-
-
-2. A few small compiler-spesific additions to make it compile with SAS/C again.
-
-3. Updated and rewritten the smakefile, so that it works again and that
-   the "unnecesarry" 'SCOPTIONS' files could be removed. Allso included
-   the cord-smakefile stuff in the main smakefile, so that the cord smakefile
-   could be removed too. By writing smake -f Smakefile.smk, both gc.lib and
-   cord.lib will be made.
-
-
-
-STILL MISSING:
-
-Programs can not be started from workbench, at least not for SAS/C. (Martin
-Tauchmanns note about that it now works with workbench is definitely wrong
-when concerning SAS/C). I guess it works if you use the old "#if 0'ed"-code,
-but I haven't tested it. I think the reason for MT to replace the
-"#if 0'ed"-code was only because it was a bit to SAS/C-spesific. But I
-don't know. An iconx-script solves this problem anyway.
-
-
-BEWARE!
-
--To run gctest, set the stack to around 200000 bytes first.
--SAS/C-spesific: cord will crash if you compile gc.lib with
- either parm=reg or parm=both. (missing legal prototypes for
- function-pointers someplace is the reason I guess.).
-
-
-tested with software: Radium, http://www.stud.ifi.uio.no/~ksvalast/radium/
-
-tested with hardware: MC68060
-
-
--ksvalast@ifi.uio.no
-
-
-===========================================================================
-			   Martin Tauchmann's notes		(1-Apr-99)
-===========================================================================
-
-Works now, also with the GNU-C compiler V2.7.2.1. <ftp://ftp.unina.it/pub/amiga/geekgadgets/amiga/m68k/snapshots/971125/amiga-bin/>
-Modify the `Makefile`
-CC=cc $(ABI_FLAG)
-to
-CC=gcc $(ABI_FLAG)
-
-TECHNICAL NOTES
-
-- `GC_get_stack_base()`, `GC_register_data_segments()` works now with every
-   C compiler; also Workbench.
-
-- Removed AMIGA_SKIP_SEG, but the Code-Segment must not be scanned by GC.
-
-
-PROBLEMS
-- When the Linker, does`t merge all Code-Segments to an single one. LD of GCC
-  do it always.
-
-- With ixemul.library V47.3, when an GC program launched from another program
-  (example: `Make` or `if_mach M68K AMIGA gctest`), `GC_register_data_segments()`
-  found the Segment-List of the caller program.
-  Can be fixed, if the run-time initialization code (for C programs, usually *crt0*)
-  support `__data` and `__bss`.
-
-- PowerPC Amiga currently not supported.
-
-- Dynamic libraries (dyn_load.c) not supported.
-
-
-TESTED WITH SOFTWARE
-
-`Optimized Oberon 2 C` (oo2c) <http://cognac.informatik.uni-kl.de/download/index.html>
-
-
-TESTED WITH HARDWARE
-
-MC68030
-
-
-CONTACT
-
-Please, contact me at <martintauchmann@bigfoot.com>, when you change the
-Amiga port. <http://martintauchmann.home.pages.de>
- 
-===========================================================================
-			   Michel Schinz's notes
-===========================================================================
-WHO DID WHAT
-
-The original Amiga port was made by Jesper Peterson. I (Michel Schinz)
-modified it slightly to reflect the changes made in the new official
-distributions, and to take advantage of the new SAS/C 6.x features. I also
-created a makefile to compile the "cord" package (see the cord
-subdirectory).
-
-TECHNICAL NOTES
-
-In addition to Jesper's notes, I have the following to say:
-
-- Starting with version 4.3, gctest checks to see if the code segment is
-  added to the root set or not, and complains if it is. Previous versions
-  of this Amiga port added the code segment to the root set, so I tried to
-  fix that. The only problem is that, as far as I know, it is impossible to
-  know which segments are code segments and which are data segments (there
-  are indeed solutions to this problem, like scanning the program on disk
-  or patch the LoadSeg functions, but they are rather complicated). The
-  solution I have chosen (see os_dep.c) is to test whether the program
-  counter is in the segment we are about to add to the root set, and if it
-  is, to skip the segment. The problems are that this solution is rather
-  awkward and that it works only for one code segment. This means that if
-  your program has more than one code segment, all of them but one will be
-  added to the root set. This isn't a big problem in fact, since the
-  collector will continue to work correctly, but it may be slower.
-
-  Anyway, the code which decides whether to skip a segment or not can be
-  removed simply by not defining AMIGA_SKIP_SEG. But notice that if you do
-  so, gctest will complain (it will say that "GC_is_visible produced wrong
-  failure indication"). However, it may be useful if you happen to have
-  pointers stored in a code segment (you really shouldn't).
-
-  If anyone has a good solution to the problem of finding, when a program
-  is loaded in memory, whether a segment is a code or a data segment,
-  please let me know.
-
-PROBLEMS
-
-If you have any problem with this version, please contact me at
-schinz@alphanet.ch (but do *not* send long files, since we pay for
-every mail!).
-
-===========================================================================
-			  Jesper Peterson's notes
-===========================================================================
-
-ADDITIONAL NOTES FOR AMIGA PORT
-
-These notes assume some familiarity with Amiga internals.
-
-WHY I PORTED TO THE AMIGA
-
-The sole reason why I made this port was as a first step in getting
-the Sather(*) language on the Amiga. A port of this language will
-be done as soon as the Sather 1.0 sources are made available to me.
-Given this motivation, the garbage collection (GC) port is rather
-minimal.
-
-(*) For information on Sather read the comp.lang.sather newsgroup.
-
-LIMITATIONS
-
-This port assumes that the startup code linked with target programs
-is that supplied with SAS/C versions 6.0 or later. This allows
-assumptions to be made about where to find the stack base pointer
-and data segments when programs are run from WorkBench, as opposed
-to running from the CLI. The compiler dependent code is all in the
-GC_get_stack_base() and GC_register_data_segments() functions, but
-may spread as I add Amiga specific features.
-
-Given that SAS/C was assumed, the port is set up to be built with
-"smake" using the "SMakefile". Compiler options in "SCoptions" can
-be set with "scopts" program. Both "smake" and "scopts" are part of
-the SAS/C commercial development system.
-
-In keeping with the porting philosophy outlined above, this port
-will not behave well with Amiga specific code. Especially not inter-
-process comms via messages, and setting up public structures like
-Intuition objects or anything else in the system lists. For the
-time being the use of this library is limited to single threaded
-ANSI/POSIX  compliant or near-complient code. (ie. Stick to stdio
-for now). Given this limitation there is currently no mechanism for
-allocating "CHIP" or "PUBLIC" memory under the garbage collector.
-I'll add this after giving it considerable thought. The major
-problem is the entire physical address space may have to me scanned,
-since there is no telling who we may have passed memory to.
-
-If you allocate your own stack in client code, you will have to
-assign the pointer plus stack size to GC_stackbottom.
-
-The initial stack size of the target program can be compiled in by
-setting the __stack symbol (see SAS documentaion). It can be over-
-ridden from the CLI by running the AmigaDOS "stack" program, or from
-the WorkBench by setting the stack size in the tool types window.
-
-SAS/C COMPILER OPTIONS (SCoptions)
-
-You may wish to check the "CPU" code option is appropriate for your
-intended target system.
-
-Under no circumstances set the "StackExtend" code option in either
-compiling the library or *ANY* client code.
-
-All benign compiler warnings have been suppressed. These mainly
-involve lack of prototypes in the code, and dead assignments
-detected by the optimizer.
-
-THE GOOD NEWS
-
-The library as it stands is compatible with the GigaMem commercial
-virtual memory software, and probably similar PD software.
-
-The performance of "gctest" on an Amiga 2630 (68030 @ 25Mhz)
-compares favourably with an HP9000 with similar architecture (a 325
-with a 68030 I think).
-
------------------------------------------------------------------------
-
-The Amiga port has been brought to you by:
-
-Jesper Peterson.
-
-jep@mtiame.mtia.oz.au		(preferred, but 1 week turnaround)
-jep@orca1.vic.design.telecom.au (that's orca<one>, 1 day turnaround)
-
-At least one of these addresses should be around for a while, even
-though I don't work for either of the companies involved.
-
diff --git a/gc/doc/README.arm.cross b/gc/doc/README.arm.cross
deleted file mode 100755
index 96744ed..0000000
--- a/gc/doc/README.arm.cross
+++ /dev/null
@@ -1,68 +0,0 @@
-From: Margaret Fleck
-
-Here's the key details of what worked for me, in case anyone else needs them.
-There may well be better ways to do some of this, but ....
-   -- Margaret
-
-
-The badge4 has a StrongArm-1110 processor and a StrongArm-1111 coprocessor.  
-
-Assume that the garbage collector distribution is unpacked into /home/arm/gc6.0,
-which is visible to both the ARM machine and a linux desktop (e.g. via NFS mounting).
-
-Assume that you have a file /home/arm/config.site with contents something like the
-example attached below.  Notice that our local ARM toolchain lives in
-/skiff/local.
-
-Go to /home/arm/gc6.0 directory.  Do
-  CONFIG_SITE=/home/arm/config.site ./configure --target=arm-linux
---prefix=/home/arm/gc6.0
-
-On your desktop, do:
-   make
-   make install
-The main garbage collector library should now be in ../gc6.0/lib/libgc.so.  
-
-To test the garbage collector, first do the following on your desktop
-   make gctest
-   ./gctest
-Then do the following on the ARM machine
-   cd .libs
-   ./lt-gctest
-
-Do not try to do "make test" (the usual way of running the test
-program).  This does not work and seems to erase some of the important
-files.
-
-The gctest program claims to have succeeded.  Haven't run any further tests
-with it, though I'll be doing so in the near future.
-
--------------------------------
-# config.site for configure
-
-# Modified from the one provided by Bradley D. LaRonde
-# Edited by Andrej Cedilnik <acedil1@csee.umbc.edu>
-# Used some of solutions by Tilman Vogel <Tilman.Vogel@web.de>
-# Ported for iPAQ Familiar by Oliver Kurth <oliver.kurth@innominate.com>
-# Further modified by Margaret Fleck for the badge4
-
-HOSTCC=gcc
-
-# Names of the cross-compilers
-CC=/skiff/local/bin/arm-linux-gcc
-CXX=/skiff/local/bin/arm-linux-gcc
-
-# The cross compiler specific options
-CFLAGS="-O2 -fno-exceptions"
-CXXFLAGS="-O2 -fno-exceptions"
-CPPFLAGS="-O2 -fno-exceptions"
-LDFLAGS=""
-
-# Some other programs
-AR=/skiff/local/bin/arm-linux-ar
-RANLIB=/skiff/local/bin/arm-linux-ranlib
-NM=/skiff/local/bin/arm-linux-nm
-ac_cv_path_NM=/skiff/local/bin/arm-linux-nm
-ac_cv_func_setpgrp_void=yes
-x_includes=/skiff/local/arm-linux/include/X11
-x_libraries=/skiff/local/arm-linux/lib/X11
diff --git a/gc/doc/README.autoconf b/gc/doc/README.autoconf
deleted file mode 100644
index 53fcf5a..0000000
--- a/gc/doc/README.autoconf
+++ /dev/null
@@ -1,59 +0,0 @@
-As of GC6.0alpha8, we attempt to support GNU-style builds based on automake,
-autoconf and libtool.  This is based almost entirely on Tom Tromey's work
-with gcj.
-
-To build and install libraries use
-
-configure; make; make install
-
-The advantages of this process are:
-
-1) It should eventually do a better job of automatically determining the
-right compiler to use, etc.  It probably already does in some cases.
-
-2) It tries to automatically set a good set of default GC parameters for
-the platform (e.g. thread support).  It provides an easier way to configure
-some of the others.
-
-3) It integrates better with other projects using a GNU-style build process.
-
-4) It builds both dynamic and static libraries.
-
-The known disadvantages are:
-
-1) The build scripts are much more complex and harder to debug (though largely
-standard).  I don't understand them all, and there's probably lots of redundant
-stuff.
-
-2) It probably doesn't work on all Un*x-like platforms yet.  It probably will
-never work on the rest.
-
-3) The scripts are not yet complete.  Some of the standard GNU targets don't
-yet work.  (Corrections/additions are very welcome.)
-
-The distribution should contain all files needed to run "configure" and "make",
-as well as the sources needed to regenerate the derived files.  (If I missed
-some, please let me know.)
-
-Note that the distribution comes with a "Makefile" which will be overwritten
-by "configure" with one that is not at all equiavelent to the original.  The
-distribution contains a copy of the original "Makefile" in "Makefile.direct". 
-
-Important options to configure:
-
-  --prefix=PREFIX         install architecture-independent files in PREFIX
-                          [/usr/local]
-  --exec-prefix=EPREFIX   install architecture-dependent files in EPREFIX
-                          [same as prefix]
-  --enable-threads=TYPE   choose threading package
-  --enable-parallel-mark  parallelize marking and free list construction
-  --enable-full-debug	include full support for pointer backtracing etc.
-
-Unless --prefix is set (or --exec-prefix or one of the more obscure options),
-make install will install libgc.a and libgc.so in /usr/local/bin, which
-would typically require the "make install" to be run as root.
-
-Most commonly --enable-threads=posix or will be needed.  --enable-parallel-mark
-is recommended for multiprocessors if it is supported on the platform.
-
-
diff --git a/gc/doc/README.changes b/gc/doc/README.changes
deleted file mode 100644
index 3b2925a..0000000
--- a/gc/doc/README.changes
+++ /dev/null
@@ -1,1653 +0,0 @@
-This is a rough history of garbage collector bugs and versions.
-
-This has been maintained with varying diligence over the years.
-
-I made an attempt to include recent contributors here.  I apologize for any
-omissions.
-
--------------------------
-
-  Version 1.3 and immediately preceding versions contained spurious
-assembly language assignments to TMP_SP.  Only the assignment in the PC/RT
-code is necessary.  On other machines, with certain compiler options,
-the assignments can lead to an unsaved register being overwritten.
-Known to cause problems under SunOS 3.5 WITHOUT the -O option.  (With
--O the compiler recognizes it as dead code.  It probably shouldn't,
-but that's another story.)
-
-  Version 1.4 and earlier versions used compile time determined values
-for the stack base.  This no longer works on Sun 3s, since Sun 3/80s use
-a different stack base.  We now use a straightforward heuristic on all
-machines on which it is known to work (incl. Sun 3s) and compile-time
-determined values for the rest.  There should really be library calls
-to determine such values.
-
-  Version 1.5 and earlier did not ensure 8 byte alignment for objects
-allocated on a sparc based machine.
-
-  Version 1.8 added ULTRIX support in gc_private.h.
-  
-  Version 1.9 fixed a major bug in gc_realloc.
-  
-  Version 2.0 introduced a consistent naming convention for collector
-routines and added support for registering dynamic library data segments
-in the standard mark_roots.c.  Most of the data structures were revamped.
-The treatment of interior pointers was completely changed.  Finalization
-was added.  Support for locking was added.  Object kinds were added.
-We added a black listing facility to avoid allocating at addresses known
-to occur as integers somewhere in the address space.  Much of this
-was accomplished by adapting ideas and code from the PCR collector.
-The test program was changed and expanded.
-
-  Version 2.1 was the first stable version since 1.9, and added support
-for PPCR.
-
-  Version 2.2 added debugging allocation, and fixed various bugs.  Among them:
-- GC_realloc could fail to extend the size of the object for certain large object sizes.
-- A blatant subscript range error in GC_printf, which unfortunately
-  wasn't exercised on machines with sufficient stack alignment constraints.
-- GC_register_displacement did the wrong thing if it was called after
-  any allocation had taken place.
-- The leak finding code would eventually break after 2048 byte
-  byte objects leaked.
-- interface.c didn't compile.
-- The heap size remained much too small for large stacks.
-- The stack clearing code behaved badly for large stacks, and perhaps
-  on HP/PA machines.
-
-  Version 2.3 added ALL_INTERIOR_POINTERS and fixed the following bugs:
-- Missing declaration of etext in the A/UX version.
-- Some PCR root-finding problems.
-- Blacklisting was not 100% effective, because the plausible future
-  heap bounds were being miscalculated.
-- GC_realloc didn't handle out-of-memory correctly.
-- GC_base could return a nonzero value for addresses inside free blocks.
-- test.c wasn't really thread safe, and could erroneously report failure
-  in a multithreaded environment.  (The locking primitives need to be
-  replaced for other threads packages.)
-- GC_CONS was thoroughly broken.
-- On a SPARC with dynamic linking, signals stayed diabled while the
-  client code was running.
-  (Thanks to Manuel Serrano at INRIA for reporting the last two.)
-  
-  Version 2.4 added GC_free_space_divisor as a tuning knob, added
-  support for OS/2 and linux, and fixed the following bugs:
-- On machines with unaligned pointers (e.g. Sun 3), every 128th word could
-  fail to be considered for marking.
-- Dynamic_load.c erroneously added 4 bytes to the length of the data and
-  bss sections of the dynamic library.  This could result in a bad memory
-  reference if the actual length was a multiple of a page.  (Observed on
-  Sun 3.  Can probably also happen on a Sun 4.)
-  (Thanks to Robert Brazile for pointing out that the Sun 3 version
-  was broken.  Dynamic library handling is still broken on Sun 3s
-  under 4.1.1U1, but apparently not 4.1.1.  If you have such a machine,
-  use -Bstatic.)
-  
-  Version 2.5 fixed the following bugs:
-- Removed an explicit call to exit(1)
-- Fixed calls to GC_printf and GC_err_printf, so the correct number of
-  arguments are always supplied.  The OS/2 C compiler gets confused if
-  the number of actuals and the number of formals differ.  (ANSI C
-  doesn't require this to work.  The ANSI sanctioned way of doing things
-  causes too many compatibility problems.)
-  
-  Version 3.0  added generational/incremental collection and stubborn
-  objects.
-
-  Version 3.1 added the following features:
-- A workaround for a SunOS 4.X SPARC C compiler
-  misfeature that caused problems when the collector was turned into
-  a dynamic library.  
-- A fix for a bug in GC_base that could result in a memory fault.
-- A fix for a performance bug (and several other misfeatures) pointed
-  out by Dave Detlefs and Al Dosser.
-- Use of dirty bit information for static data under Solaris 2.X.
-- DEC Alpha/OSF1 support (thanks to Al Dosser).
-- Incremental collection on more platforms.
-- A more refined heap expansion policy.  Less space usage by default.
-- Various minor enhancements to reduce space usage, and to reduce
-  the amount of memory scanned by the collector.
-- Uncollectable allocation without per object overhead.
-- More conscientious handling of out-of-memory conditions.
-- Fixed a bug in debugging stubborn allocation.
-- Fixed a bug that resulted in occasional erroneous reporting of smashed
-  objects with debugging allocation.
-- Fixed bogus leak reports of size 4096 blocks with FIND_LEAK.
-
-  Version 3.2 fixed a serious and not entirely repeatable bug in
-  the incremental collector.  It appeared only when dirty bit info
-  on the roots was available, which is normally only under Solaris.
-  It also added GC_general_register_disappearing_link, and some
-  testing code.  Interface.c disappeared.
-
-  Version 3.3 fixes several bugs and adds new ports:
-- PCR-specific bugs.
-- Missing locking in GC_free, redundant FASTUNLOCK
-  in GC_malloc_stubborn, and 2 bugs in
-  GC_unregister_disappearing_link.
-  All of the above were pointed out by Neil Sharman
-  (neil@cs.mu.oz.au).
-- Common symbols allocated by the SunOS4.X dynamic loader
-  were not included in the root set.
-- Bug in GC_finalize (reported by Brian Beuning and Al Dosser)
-- Merged Amiga port from Jesper Peterson (untested)
-- Merged NeXT port from Thomas Funke (significantly
-  modified and untested)
-
-  Version 3.4:
-- Fixed a performance bug in GC_realloc.
-- Updated the amiga port.
-- Added NetBSD and 386BSD ports.
-- Added cord library.
-- Added trivial performance enhancement for
-  ALL_INTERIOR_POINTERS.  (Don't scan last word.)
-  
-  Version 3.5
-- Minor collections now mark from roots only once, if that
-  doesn't cause an excessive pause.
-- The stack clearing heuristic was refined to prevent anomalies
-  with very heavily recursive programs and sparse stacks.
-- Fixed a bug that prevented mark stack growth in some cases.
-  GC_objects_are_marked should be set to TRUE after a call
-  to GC_push_roots and as part of GC_push_marked, since
-  both can now set mark bits.  I think this is only a performance
-  bug, but I wouldn't bet on it.  It's certainly very hard to argue
-  that the old version was correct.
-- Fixed an incremental collection bug that prevented it from
-  working at all when HBLKSIZE != getpagesize()
-- Changed dynamic_loading.c to include gc_priv.h before testing
-  DYNAMIC_LOADING.  SunOS dynamic library scanning
-  must have been broken in 3.4.
-- Object size rounding now adapts to program behavior.
-- Added a workaround (provided by Manuel Serrano and
-  colleagues) to a long-standing SunOS 4.X (and 3.X?) ld bug
-  that I had incorrectly assumed to have been squished.
-  The collector was broken if the text segment size was within
-  32 bytes of a multiple of 8K bytes, and if the beginning of
-  the data segment contained interesting roots.  The workaround
-  assumes a demand-loadable executable.  The original may have
-  have "worked" in some other cases.
-- Added dynamic library support under IRIX5.
-- Added support for EMX under OS/2 (thanks to Ari Huttunen).
-  
-Version 3.6:
-- fixed a bug in the mark stack growth code that was introduced
-  in 3.4.
-- fixed Makefile to work around DEC AXP compiler tail recursion
-  bug.
-
-Version 3.7:
-- Added a workaround for an HP/UX compiler bug.
-- Fixed another stack clearing performance bug.  Reworked
-  that code once more.
-  
-Version 4.0:
-- Added support for Solaris threads (which was possible
-  only by reimplementing some fraction of Solaris threads,
-  since Sun doesn't currently make the thread debugging
-  interface available).
-- Added non-threads win32 and win32S support.
-- (Grudgingly, with suitable muttering of obscenities) renamed
-  files so that the collector distribution could live on a FAT
-  file system.  Files that are guaranteed to be useless on
-  a PC still have long names.  Gc_inline.h and gc_private.h
-  still exist, but now just include  gc_inl.h and gc_priv.h.
-- Fixed a really obscure bug in finalization that could cause
-  undetected mark stack overflows.  (I would be surprised if
-  any real code ever tickled this one.)
-- Changed finalization code to dynamically resize the hash
-  tables it maintains.  (This probably does not matter for well-
-  -written code.  It no doubt does for C++ code that overuses
-  destructors.)
-- Added typed allocation primitives.  Rewrote the marker to
-  accommodate them with more reasonable efficiency.  This
-  change should also speed up marking for GC_malloc allocated
-  objects a little.  See gc_typed.h for new primitives.
-- Improved debugging facilities slightly.  Allocation time
-  stack traces are now kept by default on SPARC/SUNOS4.
-  (Thanks to Scott Schwartz.)
-- Added better support for small heap applications.
-- Significantly extended cord package.  Fixed a bug in the
-  implementation of lazily read files.  Printf and friends now
-  have cord variants.  Cord traversals are a bit faster.
-- Made ALL_INTERIOR_POINTERS recognition the default.
-- Fixed de so that it can run in constant space, independent
-  of file size.  Added simple string searching to cords and de.
-- Added the Hull-Ellis C++ interface.
-- Added dynamic library support for OSF/1.
-  (Thanks to Al Dosser and Tim Bingham at DEC.)
-- Changed argument to GC_expand_hp to be expressed
-  in units of bytes instead of heap blocks.  (Necessary
-  since the heap block size now varies depending on
-  configuration.  The old version was never very clean.)
-- Added GC_get_heap_size().  The previous "equivalent"
-  was broken.
-- Restructured the Makefile a bit.  
-
-Since version 4.0:
-- Changed finalization implementation to guarantee that
-  finalization procedures are called outside of the allocation
-  lock, making direct use of the interface a little less dangerous.
-  MAY BREAK EXISTING CLIENTS that assume finalizers
-  are protected by a lock.  Since there seem to be few multithreaded
-  clients that use finalization, this is hopefully not much of
-  a problem.
-- Fixed a gross bug in CORD_prev.
-- Fixed a bug in blacklst.c that could result in unbounded
-  heap growth during startup on machines that do not clear
-  memory obtained from the OS (e.g. win32S).
-- Ported de editor to win32/win32S.  (This is now the only
-  version with a mouse-sensitive UI.)
-- Added GC_malloc_ignore_off_page to allocate large arrays
-  in the presence of ALL_INTERIOR_POINTERS.
-- Changed GC_call_with_alloc_lock to not disable signals in
-  the single-threaded case.
-- Reduced retry count in GC_collect_or_expand for garbage
-  collecting when out of memory.
-- Made uncollectable allocations bypass black-listing, as they
-  should.
-- Fixed a bug in typed_test in test.c that could cause (legitimate)
-  GC crashes.
-- Fixed some potential synchronization problems in finalize.c
-- Fixed a real locking problem in typd_mlc.c.
-- Worked around an AIX 3.2 compiler feature that results in
-  out of bounds memory references.
-- Partially worked around an IRIX5.2 beta problem (which may
-  or may not persist to the final release).
-- Fixed a bug in the heap integrity checking code that could
-  result in explicitly deallocated objects being identified as
-  smashed.  Fixed a bug in the dbg_mlc stack saving code
-  that caused old argument pointers to be considered live.
-- Fixed a bug in CORD_ncmp (and hence CORD_str).
-- Repaired the OS2 port, which had suffered from bit rot
-  in 4.0.  Worked around what appears to be CSet/2 V1.0
-  optimizer bug.
-- Fixed a Makefile bug for target "c++".
-
-Since version 4.1:
-- Multiple bug fixes/workarounds in the Solaris threads version.
-  (It occasionally failed to locate some register contents for
-  marking.  It also turns out that thr_suspend and friends are
-  unreliable in Solaris 2.3.  Dirty bit reads appear
-  to be unreliable under some weird 
-  circumstances.  My stack marking code
-  contained a serious performance bug.  The new code is
-  extremely defensive, and has not failed in several cpu
-  hours of testing.  But  no guarantees ...)
-- Added MacOS support (thanks to Patrick Beard.)
-- Fixed several syntactic bugs in gc_c++.h and friends.  (These
-  didn't bother g++, but did bother most other compilers.)
-  Fixed gc_c++.h finalization interface.  (It didn't.)
-- 64 bit alignment for allocated objects was not guaranteed in a
-  few cases in which it should have been.
-- Added GC_malloc_atomic_ignore_off_page.
-- Added GC_collect_a_little.
-- Added some prototypes to gc.h.
-- Some other minor bug fixes (notably in Makefile).
-- Fixed OS/2 / EMX port (thanks to Ari Huttunen).
-- Fixed AmigaDOS port. (thanks to Michel Schinz).
-- Fixed the DATASTART definition under Solaris.  There
-  was a 1 in 16K chance of the collector missing the first
-  64K of static data (and thus crashing).
-- Fixed some blatant anachronisms in the README file.
-- Fixed PCR-Makefile for upcoming PPCR release.
-
-Since version 4.2:
-- Fixed SPARC alignment problem with GC_DEBUG.
-- Fixed Solaris threads /proc workaround.  The real
-  problem was an interaction with mprotect.
-- Incorporated fix from Patrick Beard for gc_c++.h (now gc_cpp.h).
-- Slightly improved allocator space utilization by
-  fixing the GC_size_map mechanism.
-- Integrated some Sony News and MIPS RISCos 4.51
-  patches.  (Thanks to Nobuyuki Hikichi of
-  Software Research Associates, Inc. Japan)
-- Fixed HP_PA alignment problem.  (Thanks to
-  xjam@cork.cs.berkeley.edu.)
-- Added GC_same_obj and friends.  Changed GC_base
-  to return 0 for pointers past the end of large objects.
-  Improved GC_base performance with ALL_INTERIOR_POINTERS
-  on machines with a slow integer mod operation.
-  Added GC_PTR_ADD, GC_PTR_STORE, etc. to prepare
-  for preprocessor.
-- changed the default on most UNIX machines to be that
-  signals are not disabled during critical GC operations.
-  This is still ANSI-conforming, though somewhat dangerous
-  in the presence of signal handlers. But the performance
-  cost of the alternative is sometimes problematic.
-  Can be changed back with a minor Makefile edit.
-- renamed IS_STRING in gc.h, to CORD_IS_STRING, thus
-  following my own naming convention.  Added the function
-  CORD_to_const_char_star.
-- Fixed a gross bug in GC_finalize.  Symptom: occasional
-  address faults in that function.  (Thanks to Anselm
-  Baird-Smith (Anselm.BairdSmith@inria.fr)
-- Added port to ICL DRS6000 running DRS/NX.  Restructured
-  things a bit to factor out common code, and remove obsolete
-  code.  Collector should now run under SUNOS5 with either
-  mprotect or /proc dirty bits.  (Thanks to Douglas Steel
-  (doug@wg.icl.co.uk)).
-- More bug fixes and workarounds for Solaris 2.X.  (These were
-  mostly related to putting the collector in a dynamic library,
-  which didn't really work before.  Also SOLARIS_THREADS
-  didn't interact well with dl_open.)  Thanks to btlewis@eng.sun.com.
-- Fixed a serious performance bug on the DEC Alpha.  The text
-  segment was getting registered as part of the root set.
-  (Amazingly, the result was still fast enough that the bug
-  was not conspicuous.) The fix works on OSF/1, version 1.3.
-  Hopefully it also works on other versions of OSF/1 ...
-- Fixed a bug in GC_clear_roots.
-- Fixed a bug in GC_generic_malloc_words_small that broke
-  gc_inl.h.  (Reported by Antoine de Maricourt.  I broke it
-  in trying to tweak the Mac port.) 
-- Fixed some problems with cord/de under Linux.
-- Fixed some cord problems, notably with CORD_riter4.
-- Added DG/UX port.
-  Thanks to Ben A. Mesander (ben@piglet.cr.usgs.gov)
-- Added finalization registration routines with weaker ordering
-  constraints.  (This is necessary for C++ finalization with
-  multiple inheritance, since the compiler often adds self-cycles.)
-- Filled the holes in the SCO port. (Thanks to Michael Arnoldus
-  <chime@proinf.dk>.)
-- John Ellis' additions to the C++ support:  From John:
-
-* I completely rewrote the documentation in the interface gc_c++.h
-(later renamed gc_cpp.h).  I've tried to make it both clearer and more
-precise.
-
-* The definition of accessibility now ignores pointers from an
-finalizable object (an object with a clean-up function) to itself.
-This allows objects with virtual base classes to be finalizable by the
-collector.  Compilers typically implement virtual base classes using
-pointers from an object to itself, which under the old definition of
-accessibility prevented objects with virtual base classes from ever
-being collected or finalized.
-
-* gc_cleanup now includes gc as a virtual base.  This was enabled by
-the change in the definition of accessibility.
-
-* I added support for operator new[].  Since most (all?) compilers
-don't yet support operator new[], it is conditionalized on
--DOPERATOR_NEW_ARRAY.  The code is untested, but its trivial and looks
-correct.
-
-* The test program test_gc_c++ (later renamed test_cpp.cc)
-tries to test for the C++-specific functionality not tested by the
-other programs.
-- Added <unistd.h> include to misc.c.  (Needed for ppcr.)
-- Added PowerMac port. (Thanks to Patrick Beard again.)
-- Fixed "srcdir"-related Makefile problems.  Changed things so
-  that all externally visible include files always appear in the
-  include subdirectory of the source.  Made gc.h directly
-  includable from C++ code.  (These were at Per
-  Bothner's suggestion.)
-- Changed Intel code to also mark from ebp (Kevin Warne's
-  suggestion).
-- Renamed C++ related files so they could live in a FAT
-  file system. (Charles Fiterman's suggestion.)
-- Changed Windows NT Makefile to include C++ support in
-  gc.lib.  Added C++ test as Makefile target.
-  
-Since version 4.3:
- - ASM_CLEAR_CODE was erroneously defined for HP
-   PA machines, resulting in a compile error.
- - Fixed OS/2 Makefile to create a library.  (Thanks to
-   Mark Boulter (mboulter@vnet.ibm.com)).
- - Gc_cleanup objects didn't work if they were created on
-   the stack.  Fixed.
- - One copy of Gc_cpp.h in the distribution was out of 
-   synch, and failed to document some known compiler
-   problems with explicit destructor invocation.  Partially
-   fixed.  There are probably other compilers on which
-   gc_cleanup is miscompiled.
- - Fixed Makefile to pass C compiler flags to C++ compiler.
- - Added Mac fixes.
- - Fixed os_dep.c to work around what appears to be
-   a new and different VirtualQuery bug under newer
-   versions of win32S.
- - GC_non_gc_bytes was not correctly maintained by
-   GC_free.  Fixed.  Thanks to James Clark (jjc@jclark.com).
- - Added GC_set_max_heap_size.
- - Changed allocation code to ignore blacklisting if it is preventing
-   use of a very large block of memory.  This has the advantage
-   that naive code allocating very large objects is much more
-   likely to work.  The downside is you might no
-   longer find out that such code should really use
-   GC_malloc_ignore_off_page.
- - Changed GC_printf under win32 to close and reopen the file
-   between calls.  FAT file systems otherwise make the log file
-   useless for debugging.
- - Added GC_try_to_collect and GC_get_bytes_since_gc.  These
-   allow starting an abortable collection during idle times. 
-   This facility does not require special OS support.  (Thanks to
-   Michael Spertus of Geodesic Systems for suggesting this.  It was
-   actually an easy addition.  Kumar Srikantan previously added a similar
-   facility to a now ancient version of the collector.  At the time
-   this was much harder, and the result was less convincing.)
- - Added some support for the Borland development environment.  (Thanks
-   to John Ellis and Michael Spertus.)
- - Removed a misfeature from checksums.c that caused unexpected 
-   heap growth.  (Thanks to Scott Schwartz.)
- - Changed finalize.c to call WARN if it encounters a finalization cycle.
-   WARN is defined in gc_priv.h to write a message, usually to stdout.
-   In many environments, this may be inappropriate.
- - Renamed NO_PARAMS in gc.h to GC_NO_PARAMS, thus adhering to my own
-   naming convention.
- - Added GC_set_warn_proc to intercept warnings.
- - Fixed Amiga port. (Thanks to Michel Schinz (schinz@alphanet.ch).)
- - Fixed a bug in mark.c that could result in an access to unmapped
-   memory from GC_mark_from_mark_stack on machines with unaligned
-   pointers.
- - Fixed a win32 specific performance bug that could result in scanning of
-   objects allocated with the system malloc.
- - Added REDIRECT_MALLOC.
-
-Since version 4.4:
- - Fixed many minor and one major README bugs. (Thanks to Franklin Chen
-   (chen@adi.com) for pointing out many of them.)
- - Fixed ALPHA/OSF/1 dynamic library support. (Thanks to Jonathan Bachrach
-   (jonathan@harlequin.com)).
- - Added incremental GC support (MPROTECT_VDB) for Linux (with some
-   help from Bruno Haible).
- - Altered SPARC recognition tests in gc.h and config.h (mostly as
-   suggested by Fergus Henderson).
- - Added basic incremental GC support for win32, as implemented by
-   Windows NT and Windows 95.  GC_enable_incremental is a noop
-   under win32s, which doesn't implement enough of the VM interface.
- - Added -DLARGE_CONFIG.
- - Fixed GC_..._ignore_off_page to also function without
-   -DALL_INTERIOR_POINTERS.
- - (Hopefully) fixed RS/6000 port.  (Only the test was broken.)
- - Fixed a performance bug in the nonincremental collector running
-   on machines supporting incremental collection with MPROTECT_VDB
-   (e.g. SunOS 4, DEC AXP).  This turned into a correctness bug under
-   win32s with win32 incremental collection.  (Not all memory protection
-   was disabled.)
- - Fixed some ppcr related bit rot.
- - Caused dynamic libraries to be unregistered before reregistering.
-   The old way turned out to be a performance bug on some machines.
- - GC_root_size was not properly maintained under MSWIN32.
- - Added -DNO_DEBUGGING and GC_dump.
- - Fixed a couple of bugs arising with SOLARIS_THREADS +
-   REDIRECT_MALLOC.
- - Added NetBSD/M68K port.  (Thanks to Peter Seebach
-   <seebs@taniemarie.solon.com>.)
- - Fixed a serious realloc bug.  For certain object sizes, the collector
-   wouldn't scan the expanded part of the object.  (Thanks to Clay Spence
-   (cds@peanut.sarnoff.com) for noticing the problem, and helping me to
-   track it down.)
-   
-Since version 4.5:
- - Added Linux ELF support.  (Thanks to Arrigo Triulzi <arrigo@ic.ac.uk>.)
- - GC_base crashed if it was called before any other GC_ routines.
-   This could happen if a gc_cleanup object was allocated outside the heap
-   before any heap allocation.
- - The heap expansion heuristic was not stable if all objects had finalization
-   enabled.  Fixed finalize.c to count memory in finalization queue and
-   avoid explicit deallocation.  Changed alloc.c to also consider this count.
-   (This is still not recommended.  It's expensive if nothing else.)  Thanks
-   to John Ellis for pointing this out.
- - GC_malloc_uncollectable(0) was broken.  Thanks to Phong Vo for pointing
-   this out.
- - The collector didn't compile under Linux 1.3.X.  (Thanks to Fred Gilham for
-   pointing this out.)  The current workaround is ugly, but expected to be
-   temporary.
- - Fixed a formatting problem for SPARC stack traces.
- - Fixed some '=='s in os_dep.c that should have been assignments.
-   Fortunately these were in code that should never be executed anyway.
-   (Thanks to Fergus Henderson.)
- - Fixed the heap block allocator to only drop blacklisted blocks in small
-   chunks.  Made BL_LIMIT self adjusting.  (Both of these were in response
-   to heap growth observed by Paul Graham.)
- - Fixed the Metrowerks/68K Mac code to also mark from a6.  (Thanks
-   to Patrick Beard.)
- - Significantly updated README.debugging.
- - Fixed some problems with longjmps out of signal handlers, especially under
-   Solaris.  Added a workaround for the fact that siglongjmp doesn't appear to
-   do the right thing with -lthread under Solaris.
- - Added MSDOS/djgpp port.  (Thanks to Mitch Harris  (maharri@uiuc.edu).)
- - Added "make reserved_namespace" and "make user_namespace".  The
-   first renames ALL "GC_xxx" identifiers as "_GC_xxx".  The second is the
-   inverse transformation.  Note that doing this is guaranteed to break all
-   clients written for the other names.
- - descriptor field for kind NORMAL in GC_obj_kinds with ADD_BYTE_AT_END
-   defined should be -ALIGNMENT not WORDS_TO_BYTES(-1).  This is
-   a serious bug on machines with pointer alignment of less than a word.
- - GC_ignore_self_finalize_mark_proc didn't handle pointers to very near the
-   end of the object correctly.  Caused failures of the C++ test on a DEC Alpha
-   with g++.
- - gc_inl.h still had problems.  Partially fixed.  Added warnings at the
-   beginning to hopefully specify the remaining dangers.
- - Added DATAEND definition to config.h.
- - Fixed some of the .h file organization.  Fixed "make floppy".
- 
-Since version 4.6:
- - Fixed some compilation problems with -DCHECKSUMS (thanks to Ian Searle)
- - Updated some Mac specific files to synchronize with Patrick Beard.
- - Fixed a serious bug for machines with non-word-aligned pointers.
-   (Thanks to Patrick Beard for pointing out the problem.  The collector
-   should fail almost any conceivable test immediately on such machines.)
-
-Since version 4.7:
- - Changed a "comment" in a MacOS specific part of mach-dep.c that caused
-   gcc to fail on other platforms.
-
-Since version 4.8
- - More README.debugging fixes.
- - Objects ready for finalization, but not finalized in the same GC
-   cycle, could be prematurely collected.  This occasionally happened
-   in test_cpp.
- - Too little memory was obtained from the system for very large
-   objects.  That could cause a heap explosion if these objects were
-   not contiguous (e.g. under PCR), and too much of them was blacklisted.
- - Due to an improper initialization, the collector was too hesitant to
-   allocate blacklisted objects immediately after system startup.
- - Moved GC_arrays from the data into the bss segment by not explicitly
-   initializing it to zero.  This significantly
-   reduces the size of executables, and probably avoids some disk accesses
-   on program startup.  It's conceivable that it might break a port that I
-   didn't test.
- - Fixed EMX_MAKEFILE to reflect the gc_c++.h to gc_cpp.h renaming which
-   occurred a while ago.
-
-Since 4.9:
- - Fixed a typo around a call to GC_collect_or_expand in alloc.c.  It broke
-   handling of out of memory.  (Thanks to Patrick Beard for noticing.)
-
-Since 4.10:
- - Rationalized (hopefully) GC_try_to_collect in an incremental collection
-   environment.  It appeared to not handle a call while a collection was in
-   progress, and was otherwise too conservative.
- - Merged GC_reclaim_or_delete_all into GC_reclaim_all to get rid of some
-   code.
- - Added Patrick Beard's Mac fixes, with substantial completely untested
-   modifications.
- - Fixed the MPROTECT_VDB code to deal with large pages and imprecise
-   fault addresses (as on an UltraSPARC running Solaris 2.5).  Note that this
-   was not a problem in the default configuration, which uses PROC_VDB.
- - The DEC Alpha assembly code needed to restore $gp between calls.
-   Thanks to Fergus Henderson for tracking this down and supplying a
-   patch.
- - The write command for "de" was completely broken for large files.
-   I used the easiest portable fix, which involved changing the semantics
-   so that f.new is written instead of overwriting f.  That's safer anyway.
- - Added README.solaris2 with a discussion of the possible problems of
-   mixing the collector's sbrk allocation with malloc/realloc.
- - Changed the data segment starting address for SGI machines.  The
-   old code failed under IRIX6.
- - Required double word alignment for MIPS.
- - Various minor fixes to remove warnings.
- - Attempted to fix some Solaris threads problems reported by Zhiying Chen.
-   In particular, the collector could try to fork a thread with the
-   world stopped as part of GC_thr_init.  It also failed to deal with
-   the case in which the original thread terminated before the whole
-   process did.
- - Added -DNO_EXECUTE_PERMISSION.  This has a major performance impact
-   on the incremental collector under Irix, and perhaps under other
-   operating systems.
- - Added some code to support allocating the heap with mmap.  This may
-   be preferable under some circumstances.
- - Integrated dynamic library support for HP.
-   (Thanks to Knut Tvedten <knuttv@ifi.uio.no>.)
- - Integrated James Clark's win32 threads support, and made a number
-   of changes to it, many of which were suggested by Pontus Rydin.
-   This is still not 100% solid.
- - Integrated Alistair Crooks' support for UTS4 running on an Amdahl
-   370-class machine.
- - Fixed a serious bug in explicitly typed allocation.  Objects requiring
-   large descriptors where handled in a way that usually resulted in
-   a segmentation fault in the marker.  (Thanks to Jeremy Fitzhardinge
-   for helping to track this down.)
- - Added partial support for GNU win32 development.  (Thanks to Fergus
-   Henderson.)
- - Added optional support for Java-style finalization semantics.  (Thanks
-   to Patrick Bridges.)  This is recommended only for Java implementations.
- - GC_malloc_uncollectable faulted instead of returning 0 when out of
-   memory.  (Thanks to dan@math.uiuc.edu for noticing.)
- - Calls to GC_base before the collector was initialized failed on a
-   DEC Alpha.  (Thanks to Matthew Flatt.)
- - Added base pointer checking to GC_REGISTER_FINALIZER in debugging
-   mode, at the suggestion of Jeremy Fitzhardinge.
- - GC_debug_realloc failed for uncollectable objects.  (Thanks to
-   Jeremy Fitzhardinge.)
- - Explicitly typed allocation could crash if it ran out of memory.
-   (Thanks to Jeremy Fitzhardinge.)
- - Added minimal support for a DEC Alpha running Linux.
- - Fixed a problem with allocation of objects whose size overflowed
-   ptrdiff_t.  (This now fails unconditionally, as it should.)
- - Added the beginning of Irix pthread support.
- - Integrated Xiaokun Zhu's fixes for djgpp 2.01.
- - Added SGI-style STL allocator support (gc_alloc.h).
- - Fixed a serious bug in README.solaris2.  Multithreaded programs must include
-   gc.h with SOLARIS_THREADS defined.
- - Changed GC_free so it actually deallocates uncollectable objects.
-   (Thanks to Peter Chubb for pointing out the problem.)
- - Added Linux ELF support for dynamic libararies.  (Thanks again to
-   Patrick Bridges.)
- - Changed the Borland cc configuration so that the assembler is not
-   required.
- - Fixed a bug in the C++ test that caused it to fail in 64-bit
-   environments.
-
-Since 4.11:
- - Fixed ElfW definition in dyn_load.c. (Thanks to Fergus Henderson.)
-   This prevented the dynamic library support from compiling on some
-   older ELF Linux systems.
- - Fixed UTS4 port (which I apparently mangled during the integration)
-   (Thanks to again to Alistair Crooks.)
- - "Make C++" failed on Suns with SC4.0, due to a problem with "bool".
-   Fixed in gc_priv.h.
- - Added more pieces for GNU win32.  (Thanks to Timothy N. Newsham.)
-   The current state of things should suffice for at least some
-   applications.
- - Changed the out of memory retry count handling as suggested by
-   Kenjiro Taura.  (This matters only if GC_max_retries > 0, which
-   is no longer the default.)
- - If a /proc read failed repeatedly, GC_written_pages was not updated
-   correctly.  (Thanks to Peter Chubb for diagnosing this.)
- - Under unlikely circumstances, the allocator could infinite loop in
-   an out of memory situation.  (Thanks again to Kenjiro Taura for
-   identifying the problem and supplying a fix.)
- - Fixed a syntactic error in the DJGPP code.  (Thanks to Fergus
-   Henderson for finding this by inspection.)  Also fixed a test program
-   problem with DJGPP (Thanks to Peter Monks.)
- - Atomic uncollectable objects were not treated correctly by the
-   incremental collector.  This resulted in weird log statistics and
-   occasional performance problems.  (Thanks to Peter Chubb for pointing
-   this out.)
- - Fixed some problems resulting from compilers that dont define
-   __STDC__.  In this case void * and char * were used inconsistently
-   in some cases.  (Void * should not have been used at all.  If
-   you have an ANSI superset compiler that does not define __STDC__,
-   please compile with -D__STDC__=0. Thanks to Manuel Serrano and others
-   for pointing out the problem.)
- - Fixed a compilation problem on Irix with -n32 and -DIRIX_THREADS.
-   Also fixed some other IRIX_THREADS problems which may or may not have
-   had observable symptoms.
- - Fixed an HP PA compilation problem in dyn_load.c.  (Thanks to
-   Philippe Queinnec.)
- - SEGV fault handlers sometimes did not get reset correctly.  (Thanks
-   to David Pickens.)
- - Added a fix for SOLARIS_THREADS on Intel.  (Thanks again to David
-   Pickens.)  This probably needs more work to become functional.
- - Fixed struct sigcontext_struct in os_dep.c for compilation under
-   Linux 2.1.X.	(Thanks to Fergus Henderson.)
- - Changed the DJGPP STACKBOTTOM and DATASTART values to those suggested
-   by Kristian Kristensen.  These may still not be right, but it is
-   it is likely to work more often than what was there before.  They may
-   even be exactly right.
- - Added a #include <string.h> to test_cpp.cc.  This appears to help
-   with HP/UX and gcc.  (Thanks to assar@sics.se.)
- - Version 4.11 failed to run in incremental mode on recent 64-bit Irix
-   kernels.  This was a problem related to page unaligned heap segments.
-   Changed the code to page align heap sections on all platforms.
-   (I had mistakenly identified this as a kernel problem earlier.
-   It was not.)
- - Version 4.11 did not make allocated storage executable, except on
-   one or two platforms, due to a bug in a #if test.  (Thanks to Dave
-   Grove for pointing this out.)
- - Added sparc_sunos4_mach_dep.s to support Sun's compilers under SunOS4.
- - Added GC_exclude_static_roots.
- - Fixed the object size mapping algorithm.  This shouldn't matter,
-   but the old code was ugly.
- - Heap checking code could die if one of the allocated objects was
-   larger than its base address.  (Unsigned underflow problem.  Thanks
-   to Clay Spence for isolating the problem.)
- - Added RS6000 (AIX) dynamic library support and fixed STACK_BOTTOM.
-   (Thanks to Fred Stearns.)
- - Added Fergus Henderson's patches for improved robustness with large
-   heaps and lots of blacklisting.
- - Added Peter Chubb's changes to support Solaris Pthreads, to support
-   MMAP allocation in Solaris, to allow Solaris to find dynamic libraries
-   through /proc, to add malloc_typed_ignore_off_page, and a few other
-   minor features and bug fixes.
- - The Solaris 2 port should not use sbrk.  I received confirmation from
-   Sun that the use of sbrk and malloc in the same program is not
-   supported.  The collector now defines USE_MMAP by default on Solaris.
- - Replaced the djgpp makefile with Gary Leavens' version.
- - Fixed MSWIN32 detection test.
- - Added Fergus Henderson's patches to allow putting the collector into
-   a DLL under GNU win32.
- - Added Ivan V. Demakov's port to Watcom C on X86.
- - Added Ian Piumarta's Linux/PowerPC port.
- - On Brian Burton's suggestion added PointerFreeGC to the placement
-   options in gc_cpp.h.  This is of course unsafe, and may be controversial.
-   On the other hand, it seems to be needed often enough that it's worth
-   adding as a standard facility.
-
-Since 4.12:
- - Fixed a crucial bug in the Watcom port.  There was a redundant decl
-   of GC_push_one in gc_priv.h.
- - Added FINALIZE_ON_DEMAND.
- - Fixed some pre-ANSI cc problems in test.c.
- - Removed getpagesize() use for Solaris.  It seems to be missing in one
-   or two versions.
- - Fixed bool handling for SPARCCompiler version 4.2.
- - Fixed some files in include that had gotten unlinked from the main
-   copy.
- - Some RS/6000 fixes (missing casts).  Thanks to Toralf Foerster.
- - Fixed several problems in GC_debug_realloc, affecting mostly the
-   FIND_LEAK case.
- - GC_exclude_static_roots contained a buggy unsigned comparison to
-   terminate a loop.  (Thanks to Wilson Ho.)
- - CORD_str failed if the substring occurred at the last possible position.
-   (Only affects cord users.)
- - Fixed Linux code to deal with RedHat 5.0 and integrated Peter Bigot's
-   os_dep.c code for dealing with various Linux versions.
- - Added workaround for Irix pthreads sigaction bug and possible signal
-   misdirection problems.
-Since alpha1:
- - Changed RS6000 STACKBOTTOM.
- - Integrated Patrick Beard's Mac changes.
- - Alpha1 didn't compile on Irix m.n, m < 6.
- - Replaced Makefile.dj with a new one from Gary Leavens.
- - Added Andrew Stitcher's changes to support SCO OpenServer.
- - Added PRINT_BLACK_LIST, to allow debugging of high densities of false
-   pointers.
- - Added code to debug allocator to keep track of return address
-   in GC_malloc caller, thus giving a bit more context.
- - Changed default behavior of large block allocator to more
-   aggressively avoid fragmentation.  This is likely to slow down the
-   collector when it succeeds at reducing space cost.
- - Integrated Fergus Henderson's CYGWIN32 changes.  They are untested,
-   but needed for newer versions.
- - USE_MMAP had some serious bugs.  This caused the collector to fail
-   consistently on Solaris with -DSMALL_CONFIG.
- - Added Linux threads support, thanks largely to Fergus Henderson.
-Since alpha2:
- - Fixed more Linux threads problems.
- - Changed default GC_free_space_divisor to 3 with new large block allocation.
-   (Thanks to Matthew Flatt for some measurements that suggest the old
-   value sometimes favors space too much over time.)
- - More CYGWIN32 fixes.
- - Integrated Tyson-Dowd's Linux-M68K port.
- - Minor HP PA and DEC UNIX fixes from Fergus Henderson.
- - Integrated Christoffe Raffali's Linux-SPARC changes.
- - Allowed for one more GC fixup iteration after a full GC in incremental
-   mode.  Some quick measurements suggested that this significantly
-   reduces pause times even with smaller GC_RATE values.
- - Moved some more GC data structures into GC_arrays.  This decreases
-   pause times and GC overhead, but makes debugging slightly less convenient.
- - Fixed namespace pollution problem ("excl_table").
- - Made GC_incremental a constant for -DSMALL_CONFIG, hopefully shrinking
-   that slightly.
- - Added some win32 threads fixes.
- - Integrated Ivan Demakov and David Stes' Watcom fixes.
- - Various other minor fixes contributed by many people.
- - Renamed config.h to gcconfig.h, since config.h tends to be used for
-   many other things.
- - Integrated Matthew Flatt's support for 68K MacOS "far globals".
- - Fixed up some of the dynamic library Makefile targets for consistency
-   across platforms.
- - Fixed a USE_MMAP typo that caused out-of-memory handling to fail
-   on Solaris.
- - Added code to test.c to test thread creation a bit more.
- - Integrated GC_win32_free_heap, as suggested by Ivan Demakov.
- - Fixed Solaris 2.7 stack base finding problem.  (This may actually
-   have been done in an earlier alpha release.)
-Since alpha3:
- - Fixed MSWIN32 recognition test, which interfered with cygwin.
- - Removed unnecessary gc_watcom.asm from distribution.  Removed
-   some obsolete README.win32 text.
- - Added Alpha Linux incremental GC support.  (Thanks to Philipp Tomsich
-   for code for retrieving the fault address in a signal handler.)
-   Changed Linux signal handler context argument to be a pointer.
- - Took care of some new warnings generated by the 7.3 SGI compiler.
- - Integrated Phillip Musumeci's FreeBSD/ELF fixes.
- - -DIRIX_THREADS was broken with the -o32 ABI (typo in gc_priv.h>
-
-Since 4.13:
- - Fixed GC_print_source_ptr to not use a prototype.
- - generalized CYGWIN test.
- - gc::new did the wrong thing with PointerFreeGC placement.
-   (Thanks to Rauli Ruohonen.)
- - In the ALL_INTERIOR_POINTERS (default) case, some callee-save register
-   values could fail to be scanned if the register was saved and
-   reused in a GC frame.  This showed up in verbose mode with gctest
-   compiled with an unreleased SGI compiler.  I vaguely recall an old
-   bug report that may have been related.  The bug was probably quite old.
-   (The problem was that the stack scanning could be deferred until
-   after the relevant frame was overwritten, and the new save location
-   might be outside the scanned area.  Fixed by more eager stack scanning.)
- - PRINT_BLACK_LIST had some problems.  A few source addresses were garbage.
- - Replaced Makefile.dj and added -I flags to cord make targets.
-   (Thanks to Gary Leavens.)
- - GC_try_to_collect was broken with the nonincremental collector.
- - gc_cleanup destructors could pass the wrong address to
-   GC_register_finalizer_ignore_self in the presence of multiple
-   inheritance.  (Thanks to Darrell Schiebel.)
- - Changed PowerPC Linux stack finding code.
-
-Since 4.14alpha1
- - -DSMALL_CONFIG did not work reliably with large (> 4K) pages.
-   Recycling the mark stack during expansion could result in a size
-   zero heap segment, which confused things.  (This was probably also an
-   issue with the normal config and huge pages.)
- - Did more work to make sure that callee-save registers were scanned
-   completely, even with the setjmp-based code.  Added USE_GENERIC_PUSH_REGS
-   macro to facilitate testing on machines I have access to.
- - Added code to explicitly push register contents for win32 threads.
-   This seems to be necessary.  (Thanks to Pierre de Rop.)
-
-Since 4.14alpha2
- - changed STACKBOTTOM for DJGPP (Thanks to Salvador Eduardo Tropea).
- 
-Since 4.14
- - Reworked large block allocator.  Now uses multiple doubly linked free
-   lists to approximate best fit.
- - Changed heap expansion heuristic.  Entirely free blocks are no longer
-   counted towards the heap size.  This seems to have a major impact on
-   heap size stability; the old version could expand the heap way too
-   much in the presence of large block fragmentation.
- - added -DGC_ASSERTIONS and some simple assertions inside the collector.
-   This is mainlyt for collector debugging.
- - added -DUSE_MUNMAP to allow the heap to shrink.  Suupported on only
-   a few UNIX-like platforms for now.
- - added GC_dump_regions() for debugging of fragmentation issues.
- - Changed PowerPC pointer alignment under Linux to 4.  (This needs
-   checking by someone who has one.  The suggestions came to me via a
-   rather circuitous path.)
- - Changed the Linux/Alpha port to walk the data segment backwards until
-   it encounters a SIGSEGV.  The old way to find the start of the data
-   segment broke with a recent release.
- - cordxtra.c needed to call GC_REGISTER_FINALIZER instead of
-   GC_register_finalizer, so that it would continue to work with GC_DEBUG.
- - allochblk sometimes cleared the wrong block for debugging purposes
-   when it dropped blacklisted blocks.  This could result in spurious
-   error reports with GC_DEBUG.
- - added MACOS X Server support.  (Thanks to Andrew Stone.)
- - Changed the Solaris threads code to ignore stack limits > 8 MB with
-   a warning.  Empirically, it is not safe to access arbitrary pages
-   in such large stacks.  And the dirty bit implementation does not
-   guarantee that none of them will be accessed.
- - Integrated Martin Tauchmann's Amiga changes.
- - Integrated James Dominy's OpenBSD/SPARC port.
-
-Since 5.0alpha1
- - Fixed bugs introduced in alpha1 (OpenBSD & large block initialization).
- - Added -DKEEP_BACK_PTRS and backptr.h interface.  (The implementation
-   idea came from Al Demers.)
-
-Since 5.0alpha2
- - Added some highly incomplete code to support a copied young generation.
-   Comments on nursery.h are appreciated.
- - Changed -DFIND_LEAK, -DJAVA_FINALIZATION, and -DFINALIZE_ON_DEMAND,
-   so the same effect could be obtained with a runtime switch.   This is
-   a step towards standardizing on a single dynamic GC library.
- - Significantly changed the way leak detection is handled, as a consequence
-   of the above.
-
-Since 5.0 alpha3
- - Added protection fault handling patch for Linux/M68K from Fergus
-   Henderson and Roman Hodek.
- - Removed the tests for SGI_SOURCE in new_gc_alloc.h.  This was causing that
-   interface to fail on nonSGI platforms.
- - Changed the Linux stack finding code to use /proc, after changing it
-   to use HEURISTIC1.  (Thanks to David Mossberger for pointing out the
-   /proc hook.)
- - Added HP/UX incremental GC support and HP/UX 11 thread support.
-   Thread support is currently still flakey.
- - Added basic Linux/IA64 support.
- - Integrated Anthony Green's PicoJava support.
- - Integrated Scott Ananian's StrongARM/NetBSD support.
- - Fixed some fairly serious performance bugs in the incremental
-   collector.  These have probably been there essentially forever.
-   (Mark bits were sometimes set before scanning dirty pages.
-   The reclaim phase unnecessarily dirtied full small object pages.)
- - Changed the reclaim phase to ignore nearly full pages to avoid
-   touching them.
- - Limited GC_black_list_spacing to roughly the heap growth increment.
- - Changed full collection triggering heuristic to decrease full GC
-   frequency by default, but to explicitly trigger full GCs during
-   heap growth.  This doesn't always improve things, but on average it's
-   probably a win.
- - GC_debug_free(0, ...) failed.  Thanks to Fergus Henderson for the
-   bug report and fix.
-
-Since 5.0 alpha4
- - GC_malloc_explicitly_typed and friends sometimes failed to
-   initialize first word.
- - Added allocation routines and support in the marker for mark descriptors
-   in a type structure referenced by the first word of an object.  This was
-   introduced to support gcj, but hopefully in a way that makes it
-   generically useful.
- - Added GC_requested_heapsize, and inhibited collections in nonincremental
-   mode if the actual used heap size is less than what was explicitly
-   requested.
- - The Solaris pthreads version of GC_pthread_create didn't handle a NULL
-   attribute pointer.  Solaris thread support used the wrong default thread
-   stack size.  (Thanks to Melissa O'Neill for the patch.)
- - Changed PUSH_CONTENTS macro to no longer modify first parameter.
-   This usually doesn't matter, but it was certainly an accident waiting
-   to happen ...
- - Added GC_register_finalizer_no_order and friends to gc.h.  They're
-   needed by Java implementations.
- - Integrated a fix for a win32 deadlock resulting from clock() calling
-   malloc.  (Thanks to Chris Dodd.)
- - Integrated Hiroshi Kawashima's port to Linux/MIPS.  This was designed
-   for a handheld platform, and may or may not be sufficient for other
-   machines.
- - Fixed a va_arg problem with the %c specifier in cordprnt.c.  It appears
-   that this was always broken, but recent versions of gcc are the first to
-   report the (statically detectable) bug.
- - Added an attempt at a more general solution to dlopen races/deadlocks.
-   GC_dlopen now temporarily disables collection.  Still not ideal, but ...
- - Added -DUSE_I686_PREFETCH, -DUSE_3DNOW_PREFETCH, and support for IA64
-   prefetch instructions.  May improve performance measurably, but I'm not
-   sure the code will run correctly on processors that don't support the
-   instruction.  Won't build except with very recent gcc.
- - Added caching for header lookups in the marker.  This seems to result
-   in a barely measurable performance gain.  Added support for interleaved
-   lookups of two pointers, but unconfigured that since the performance
-   gain is currently near zero, and it adds to code size.
- - Changed Linux DATA_START definition to check both data_start and
-   __data_start, since nothing else seems to be portable.
- - Added -DUSE_LD_WRAP to optionally take advantage of the GNU ld function
-   wrapping mechanism.  Probably currently useful only on Linux.
- - Moved some variables for the scratch allocator into GC_arrays, on
-   Martin Hirzel's suggestion.
- - Fixed a win32 threads bug that caused the collector to not look for
-   interior pointers from one of the thread stacks without
-   ALL_INTERIOR_POINTERS.  (Thanks to Jeff Sturm.)
- - Added Mingw32 support.  (Thanks again to Jeff Sturm for the patch.)
- - Changed the alpha port to use the generic register scanning code instead
-   of alpha_mach_dep.s.  Alpha_mach_dep.s doesn't look for pointers in fp
-   registers, but gcc sometimes spills pointers there.  (Thanks to Manuel
-   Serrano for helping me debug this by email.)  Changed the IA64 code to
-   do something similar for similar reasons.
-
-[5.0alpha5 doesn't really exist, but it may have escaped.]
-
-Since 5.0alpha6:
- - -DREDIRECT_MALLOC was broken in alpha6. Fixed.
- - Cleaned up gc_ccp.h slightly, thus also causing the HP C++ compiler to
-   accept it.
- - Removed accidental reference to dbg_mlc.c, which caused dbg_mlc.o to be
-   linked into every executable.
- - Added PREFETCH to bitmap marker.  Changed it to use the header cache.
- - GC_push_marked sometimes pushed one object too many, resulting in a
-   segmentation fault in GC_mark_from_mark_stack.  This was probably an old
-   bug.  It finally showed up in gctest on win32.
- - Gc_priv.h erroneously #defined GC_incremental to be TRUE instead of FALSE
-   when SMALL_CONFIG was defined.  This was no doubt a major performance bug for
-   the default win32 configuration.
- - Removed -DSMALL_CONFIG from NT_MAKEFILE.  It seemed like an anchronism now
-   that the average PC has 64MB or so.
- - Integrated Bryce McKinley's patches for linux threads and dynamic loading
-   from the libgcj tree.  Turned on dynamic loading support for Linux/PPC.
- - Changed the stack finding code to use environ on HP/UX.  (Thanks
-   to Gustavo Rodriguez-Rivera for the suggestion.)  This should probably
-   be done on other platforms, too.  Since I can't test those, that'll
-   wait until after 5.0.
-
-Since 5.0alpha7:
- - Fixed threadlibs.c for linux threads.  -DUSE_LD_WRAP was broken and
-   -ldl was omitted.  Fixed Linux stack finding code to handle
-   -DUSE_LD_WRAP correctly.
- - Added MSWIN32 exception handler around marker, so that the collector
-   can recover from root segments that are unmapped during the collection.
-   This caused occasional failures under Windows 98, and may also be
-   an issue under Windows NT/2000.
-
-Since 5.0
- - Fixed a gc.h header bug which showed up under Irix.  (Thanks to
-   Dan Sullivan.)
- - Fixed a typo in GC_double_descr in typd_mlc.c.
-   This probably could result in objects described by array descriptors not
-   getting traced correctly.  (Thanks to Ben Hutchings for pointing this out.)
- - The block nearly full tests in reclaim.c were not correct for 64 bit
-   environments.  This could result in unnecessary heap growth under unlikely
-   conditions.
-
-Since 5.1
- - dyn_load.c declared GC_scratch_last_end_ptr as an extern even if it
-   was defined as a macro.  This prevented the collector from building on
-   Irix.
- - We quietly assumed that indirect mark descriptors were never 0.
-   Our own typed allocation interface violated that.  This could result
-   in segmentation faults in the marker with typed allocation.
- - Fixed a _DUSE_MUNMAP bug in the heap block allocation code.
-   (Thanks to Ben Hutchings for the patch.)
- - Taught the collector about VC++ handling array operator new.
-   (Thanks again to Ben Hutchings for the patch.)
- - The two copies of gc_hdrs.h had diverged.  Made one a link to the other
-   again.
-
-Since 5.2  (A few 5.2 patches are not in 6.0alpha1)
- - Fixed _end declaration for OSF1.
- - There were lots of spurious leak reports in leak detection mode, caused
-   by the fact that some pages were not being swept, and hence unmarked
-   objects weren't making it onto free lists.  (This bug dated back to 5.0.)
- - Fixed a typo in the liblinuxgc.so Makefile rule.
- - Added the GetExitCodeThread to Win32 GC_stop_world to (mostly) work
-   around a Windows 95 GetOpenFileName problem.  (Thanks to Jacob Navia.)
-
-Since 5.3
- - Fixed a typo that prevented compilation with -DUSE_3DNOW_PREFETCH.
-   (Thanks to Shawn Wagner for actually testing this.)
- - Fixed GC_is_thread_stack in solaris_threads.c.  It forgot to return a value
-   in the common case.  I wonder why nobody noticed?
- - Fixed another silly syntax problem in GC_double_descr.  (Thanks to
-   Fergus Henderson for finding it.)
- - Fixed a GC_gcj_malloc bug: It tended to release the allocator lock twice.
-
-Since 5.4  (A few 5.3 patches are not in 6.0alpha2)
- - Added HP/PA prefetch support.
- - Added -DDBG_HDRS_ALL and -DSHORT_DBG_HDRS to reduce the cost and improve
-   the reliability of generating pointer backtrace information, e.g. in
-   the Bigloo environment.
- - Added parallel marking support (-DPARALLEL_MARK).  This currently
-   works only under IA32 and IA64 Linux, but it shouldn't be hard to adapt
-   to other platforms.  This is intended to be a lighter-weight (less
-   new code, probably not as scalable) solution than the work by Toshio Endo
-   et al, at the University of Tokyo.  A number of their ideas were
-   reused, though the code wasn't, and the underlying data structure
-   is significantly different.  In particular, we keep the global mark
-   stack as a single shared data structure, but most of the work is done
-   on smaller thread-local mark stacks.
- - Changed GC_malloc_many to be cheaper, and to require less mutual exclusion
-   with -DPARALLEL_MARK.
- - Added full support for thread local allocation under Linux
-   (-DTHREAD_LOCAL_ALLOC).  This is a thin veneer on GC_malloc_many, and
-   should be easily portable to other platforms, especially those that
-   support pthreads.
- - CLEAR_DOUBLE was not always getting invoked when it should have been.
- - GC_gcj_malloc and friends used different out of memory handling than
-   everything else, probably because I forgot about one when I implemented
-   the other.  They now both call GC_oom_fn(), not GC_oom_action().
- - Integrated Jakub Jelinek's fixes for Linux/SPARC.
- - Moved GC_objfreelist, GC_aobjfreelist, and GC_words_allocd out of
-   GC_arrays, and separately registered the first two as excluded roots.
-   This makes code compiled with gc_inl.h less dependent on the
-   collector version.  (It would be nice to remove the inclusion of
-   gc_priv.h by gc_inl.h completely, but we're not there yet.  The
-   locking definitions in gc_priv.h are still referenced.)
-   This change was later coniditoned on SEPARATE_GLOBALS, which
-   is not defined by default, since it involves a performance hit.
- - Register GC_obj_kinds separately as an excluded root region.  The
-   attempt to register it with GC_arrays was usually failing.  (This wasn't
-   serious, but seemed to generate some confusion.) 
- - Moved backptr.h to gc_backptr.h.
-
-Since 6.0alpha1
- - Added USE_MARK_BYTES to reduce the need for compare-and-swap on platforms
-   for which that's expensive.
- - Fixed a locking bug ib GC_gcj_malloc and some locking assertion problems.
- - Added a missing volatile to OR_WORD and renamed the parameter to
-   GC_compare_and_swap so it's not a C++ reserved word.  (Thanks to
-   Toshio Endo for pointing out both of those.)
- - Changed Linux dynamic library registration code to look at /proc/self/maps
-   instead of the rld data structures when REDIRECT_MALLOC is defined.
-   Otherwise some of the rld data data structures may be prematurely garbage
-   collected.  (Thanks to Eric Benson for helping to track this down.)
- - Fixed USE_LD_WRAP a bit more, so it should now work without threads.
- - Renamed XXX_THREADS macros to GC_XXX_THREADS for namespace correctness.
-   Tomporarily added some backward compatibility definitions.  Renamed
-   USE_LD_WRAP to GC_USE_LD_WRAP.
- - Many MACOSX POWERPC changes, some additions to the gctest output, and
-   a few minor generic bug fixes.  (Thanks to Dietmar Planitzer.)
-
-Since 6.0 alpha2
- - Fixed the /proc/self/maps code to not seek, since that apparently is not
-   reliable across all interesting kernels.
- - Fixed some compilation problems in the absence of PARALLEL_MARK
-   (introduced in alpha2).
- - Fixed an algorithmic problem with PARALLEL_MARK.  If work needs to
-   be given back to the main mark "stack", the BOTTOM entries of the local
-   stack should be given away, not the top ones.  This has substantial
-   performance impact, especially for > 2 processors, from what I can tell.
- - Extracted gc_lock.h from gc_priv.h.  This should eventually make it a
-   bit easier to avoid including gc_priv.h in clients.
- - Moved all include files to include/ and removed duplicate links to the
-   same file.  The old scheme was a bad idea because it was too easy to get the
-   copies out of sync, and many systems don't support hard links.
-   Unfortunately, it's likely that I broke some of the non-Unix Makefiles in
-   the process, although I tried to update them appropriately.
- - Removed the partial support for a copied nursery.  It's not clear that
-   this would be a tremendous win, since we don't consistently lose to
-   generational copying collectors.  And it would significantly complicate
-   many things.  May be reintroduced if/when it really turns out to win.
- - Removed references to IRIX_JDK_THREADS, since I believe there never
-   were and never will be any clients.
- - Added some code to linux_threads.c to possibly support HPUX threads
-   using the Linux code.  Unfortunately, it doesn't work yet, and is
-   currently disabled.
- - Added support under Linux/X86 for saving the call chain, both in (debug)
-   objects for client debugging, and in GC_arrays._last_stack for GC
-   debugging.  This was previously supported only under Solaris.  It is
-   not enabled by default under X86, since it requires that code be compiled
-   to explicitly dave frame pointers on the call stack.  (With gcc this
-   currently happens by default, but is often turned off explicitly.)
-   To turn it on, define SAVE_CALL_CHAIN.
- 
-Since 6.0 alpha3
- - Moved up the detection of mostly full blocks to the initiatiation of the
-   sweep phase.  This eliminates some lock conention in the PARALLEL_MARK case,
-   as multiple threads try to look at mostly full blocks concurrently.
- - Restored the code in GC_malloc_many that grabs a prefix of the global
-   free list.  This avoids the case in which every GC_malloc_many call
-   tries and fails to allocate a new heap block, and the returns a single
-   object from the global free list.
- - Some minor fixes in new_hblk.c.  (Attempted to build free lists in order
-   of increasing addresses instead of decreasing addresses for cache performance
-   reasons.  But this seems to be only a very minor gain with -DEAGER_SWEEP,
-   and a loss in other cases.  So the change was backed out.)
- - Fixed some of the documentation.  (Thanks in large part to Fergus
-   Henderson.)
- - Fixed the Linux USE_PROC_FOR_LIBRARIES code to deal with apps that perform
-   large numbers of mmaps.  (Thanks to Eric Benson.)  Also fixed that code to
-   deal with short reads.
- - Added GC_get_total_bytes(). 
- - Fixed leak detection mode to avoid spurious messages under linuxthreads.
-   (This should also now be easy for the other supported threads packages.
-   But the code is tricky enough that I'm hesitant to do it without being able
-   to test.  Everything allocated in the GC thread support itself should be
-   explicitly deallocated.)
- - Made it possible (with luck) to redirect malloc to GC_local_malloc.
-
-Since 6.0 alpha4
- - Changed the definition of GC_pause in linux_threads.c to use a volatile
-   asm.  Some versions of gcc apparently optimize away writes to local volatile
-   variables.  This caused poor locking behaviour starting at about
-   4 processors.
- - Added GC_start_blocking(), GC_end_blocking() calls and wrapper for sleep
-   to linux_threads.c.
-   The first two calls could be used to generally avoid sending GC signals to
-   blocked threads, avoiding both premature wakeups and unnecessary overhead.
- - Fixed a serious bug in thread-local allocation.  At thread termination,
-   GC_free could get called on small integers.  Changed the code for thread
-   termination to more efficiently return left-over free-lists.
- - Integrated Kjetil Matheussen's BeOS support.
- - Rearranged the directory structure to create the doc and tests
-   subdirectories.
- - Sort of integrated Eric Benson's patch for OSF1.  This provided basic
-   OSF1 thread support by suitably extending hpux_irix_threads.c.  Based
-   on earlier email conversations with David Butenhof, I suspect that it
-   will be more reliable in the long run to base this on linux_threads.c
-   instead.  Thus I attempted to patch up linux_threads.c based on Eric's code.
-   The result is almost certainly broken, but hopefully close enough that
-   someone with access to a machine can pick it up.
- - Integrated lots of minor changes from the NetBSD distribution.  (These
-   were supplied by David Brownlee.  I'm not sure about the original
-   authors.)
- - Hacked a bit more on the HP/UX thread-support in linux_threads.c.  It
-   now appears to work in the absence of incremental collection.  Renamed
-   hpux_irix_threads.c back to irix_threads.c, and removed the attempt to
-   support HPUX there.
- - Changed gc.h to define _REENTRANT in cases in which it should already
-   have been defined. It is still safer to also define it on the command
-   line. 
-
-Since 6.0alpha5:
- - Changed the definition of DATASTART on ALPHA and IA64, where data_start
-   and __data_start are not defined by earlier versions of glibc.  This might
-   need to be fixed on other platforms as well.
- - Changed the way the stack base and backing store base are found on IA64.
-   This should now remain reliable on future kernels.  But since it relies
-   on /proc, it will no longer work in the simulated NUE environment.
- - Made the call to random() in dbg_mlc.c with -DKEEP_BACK_PTRS dependent
-   on the OS.  On non-Unix systems, rand() should be used instead.  Handled
-   small RAND_MAX.  (Thanks to Peter Ross for pointing this out.)
- - Fixed the cord make rules to create the cord subdirectory, if necessary.
-   (Thanks to Doug Moen.)
- - Changed fo_object_size calculation in finalize.c.  Turned finalization
-   of nonheap object into a no-op.  Removed anachronism from GC_size()
-   implementation.
- - Changed GC_push_dirty call in solaris_threads.c to GC_push_selected.
-   It was missed in a previous renaming. (Thanks to Vladimir Tsichevski
-   for pointing this out.)
- - Arranged to not not mask SIGABRT in linux_threads.c.  (Thanks to Bryce
-   McKinlay.) 
- - Added GC_no_dls hook for applications that want to register their own
-   roots.
- - Integrated Kjetil Matheussen's Amiga changes.
- - Added FREEBSD_STACKBOTTOM.  Changed the X86/FreeBSD port to use it.
-   (Thanks to Matthew Flatt.)
- - Added pthread_detach interception for platforms supported by linux_threads.c
-   and irix_threads.c.  Should also be added for Solaris?
- - Changed the USE_MMAP code to check for the case in which we got the
-   high end of the address space, i.e. mem_ptr + mem_sz == 0.  It appears
-   that this can happen under Solaris 7.  It seems to be allowed by what
-   I would claim is an oversight in the mmap specification.  (Thanks to Toshio
-   Endo for pointing out the problem.)
- - Cleanup of linux_threads.c.  Some code was originally cloned from
-   irix_threads.c and now unnecessary.  Some comments were obviously wrong.
- - (Mostly) fixed a longstanding problem with setting of dirty bits from
-   a signal handler.  In the presence of threads, dirty bits could get lost,
-   since the etting of a bit in the bit vector was not atomic with respect
-   to other updates.  The fix is 100% correct only for platforms for which
-   GC_test_and_set is defined.  The goal is to make that all platforms with
-   thread support.  Matters only if incremental GC and threads are both
-   enabled.
- - made GC_all_interior_pointers (a.k.a. ALL_INTERIOR_POINTERS) an
-   initialization time, instead of build-time option.  This is a 
-   nontrivial, high risk change.  It should slow down the code measurably
-   only if MERGE_SIZES is not defined, which is a very nonstandard
-   configuration.   
- - Added doc/README.environment, and implemented what it describes.  This
-   allows a number of additional configuration options to be set through
-   the environment.  It documents a few previously undocumented options.
- - Integrated Eric Benson's leak testing improvements.
- - Removed the option to throw away the beginning of each page (DISCARD_WORDS).
-   This became less and less useful as processors enforce stricter alignment.
-   And it hadn't been tested in ages, and was thus probably broken anyway.
-
-Since 6.0alpha6:
- - Added GC_finalizer_notifier.  Fixed GC_finalize_on_demand.  (The variable
-   actually wasn't being tested at the right points.  The build-time flag
-   was.)
- - Added Tom Tromey's S390 Linux patch.
- - Added code to push GC_finalize_now in GC_push_finalizer_structures.
-   (Thanks to Matthew Flatt.)
- - Added GC_push_gc_structures() to push all GC internal roots.
- - Integrated some FreeBSD changes from Matthew Flatt.
- - It looks like USRSTACK is not always correctly defined under Solaris.
-   Hacked gcconfig.h to attempt to work around the problem.  The result
-   is not well tested.  (Thanks again to Matthew Flatt for pointing this
-   out.  The gross hack is mine. - HB)
- - Added Ji-Yong Chung's win32 threads and C++ fixes.
- - Arranged for hpux_test_and_clear.s to no longer be needed or built.
-   It was causing build problems with gas, and it's not clear this is
-   better than the pthreads alternative on this platform.
- - Some MINGW32 fixes from Hubert Garavel.
- - Added Initial Hitachi SH4 port from Kaz Kojima.
- - Ported thread-local allocation and parallel mark code to HP/UX on PA_RISC.
- - Made include/gc_mark.h more public and separated out the really private
-   pieces.  This is probably still not quite sufficient for clients that
-   want to supply their own kind of type information.  But it's a start.
-   This involved lots of identifier renaming to make it namespace clean.
- - Added GC_dont_precollect for clients that need complete control over
-   the root set.
- - GC_is_visible didn't do the right thing with gcj objects.  (Not that
-   many people are likely to care, but ...)
- - Don't redefine read with GC_USE_LD_WRAP.
- - Initial port to LINUX/HP_PA.  Incremental collection and threads are not
-   yet supported.  (Incremental collection should work if you have the
-   right kernel.  Threads may work with a sufficiently patched pthread
-   library.)
- - Changed gcconfig.h to recognize __i386__ as an alternative to i386 in
-   many places.  (Thanks to Benjamin Lerman.)
- - Made win32_threads.c more tolerant of detaching a thread that it didn't
-   know about.  (Thanks to Paul Nash.)
- - Added Makefile.am and configure.in from gcc to the distribution, with
-   minimal changes.  For the moment, those are just placeholders.  In the
-   future, we're planning to switch to a GNU-style build environment for
-   Un*x-like systems, though the old Makefile will remain as a backup.
- - Turned off STUBBORN_ALLOC by default, and added it back as a Makefile
-   option.
- - Redistributed some functions between malloc.c and mallocx.c, so that
-   simple statically linked apps no longer pull in mallocx.o.
- - Changed large object allocation to clear the first and last few words
-   of each block before releassing the lock.  Otherwise the marker could see
-   objects with nonsensical type descriptors.
- - Fixed a couple of subtle problems that could result in not recognizing
-   interior pointers from the stack.  (I believe these were introduced
-   in 6.0alpha6.)
- - GC_debug_free_inner called GC_free, which tried to reacquire the
-   allocator lock, and hence deadlocked.  (DBG_HDRS_ALL probably never worked
-   with threads?)
- - Fixed several problems with back traces.  Accidental references to a free
-   list could cause the free list pointer to be overwritten by a back pointer.
-   There seemed to be some problems with the encoding of root and finalizer
-   references.
-  
-Since 6.0alpha7:
- - Changed GC_debug_malloc_replacement and GC_debug_realloc_replacement
-   so that they compile under Irix.  (Thanks to Dave Love.)
- - Updated powerpc_macosx_mach_dep.s so that it works if the collector
-   is in a dynamic library.  (Thanks to Andrew Begel.)
- - Transformed README.debugging into debugging.html, updating and
-   expanding it in the process.  Added gcdescr.html and tree.html
-   from the web site to the GC distribution.
- - Fixed several problems related to PRINT_BLACK_LIST. This involved
-   restructuring some of the marker macros.
- - Fixed some problems with the sizing of objects with debug information.
-   Finalization was broken KEEP_BACK_PTRS or PRINT_BLACK_LIST.  Reduced the
-   object size with SHORT_DEBUG_HDRS by another word.
- - The "Needed to allocate blacklisted ..." warning had inadvertently
-   been turned off by default, due to a buggy test in allchblk.c.  Turned
-   it back on.
- - Removed the marker macros to deal with 2 pointers in interleaved fashion.
-   They were messy and the performance improvement seemed minimal.  We'll
-   leave such scheduling issues to the compiler.
- - Changed Linux/PowerPC test to also check for __powerpc__ in response
-   to a discussion on the gcc mailing list.
- - On Matthew Flatt's suggestion removed the "static" from the jmp_buf
-   declaration in GC_generic_push_regs.  This was causing problems in
-   systems that register all of their own roots.  It looks far more correct
-   to me without the "static" anyway. 
- - Fixed several problems with thread local allocation of pointerfree or
-   typed objects.  The collector was reclaiming thread-local free lists, since
-   it wasn't following the link fields.
- - There was apparently a long-standing race condition related to multithreaded
-   incremental collection.  A collection could be started and a thread stopped
-   between the memory unprotect system call and the setting of the
-   corresponding dirt bit.  I believe this did not affect Solaris or PCR, which
-   use a different dirty-bit implementation.  Fixed this by installing
-   signal handlers with sigaction instead of signal, and disabling the thread
-   suspend signal while in the write-protect handler.  (It is unclear
-   whether this scenario ever actually occurred.  I found it while tracking
-   down the following:)
- - Incremental collection did not cooperate correctly with the PARALLEL_MARK
-   implementation of GC_malloc_many or the local_malloc primitves.  It still
-   doesn't work well, but it shouldn't lose memory anymore.
- - Integrated some changes from the gcc source tree that I had previously
-   missed.  (Thanks to Bryce McKinley for the reminder/diff.)
- - Added Makefile.direct as a copy of the default Makefile, which would
-   normally be overwritten if configure is run.
- - Changed the gc.tar target in Makefile.direct to embed the version number
-   in the gc directory name.  This will affect future tar file distributions.
- - Changed the Irix dynamic library finding code to no longer try to
-   eliminate writable text segments under Irix6.x, since that is probably no
-   longer necessary, and can apparently be unsafe on occasion.  (Thanks to
-   Shiro Kawai for pointing this out.)
- - GC_cleanup with GC_DEBUG enabled passed a real object base address to
-   GC_debug_register_finalizer_ignore_self, which expected a pointer past the
-   debug header.  Call GC_register_finalizer_ignore_self instead, even with
-   debugging enabled.  (Thanks to Jean-Daniel Fekete for catching this.)
- - The collector didn't build with call chain saving enabled but NARGS=0.
-   (Thanks to Maarten Thibaut.)
- - Fixed up the GNU-style build files enough so that they work in some
-   obvious cases.
- - Added initial port to Digital Mars compiler for win32. (Thanks to Walter
-   Bright.)
-
-Since 6.0alpha8:
- - added README.macros.
- - Made gc.mak a symbolic link to work around winzip's tendency to ignore
-   hard links.
- - Simplified the setting of NEED_FIND_LIMIT in os_dep.c, possibly breaking
-   it on untested platforms.
- - Integrated initial GNU HURD port. (Thanks to Chris Lingard and Igor
-   Khavkine.)
- - A few more fixes for Digital Mars compiler (Walter Bright).
- - Fixed gcc version recognition.  Renamed OPERATOR_NEW_ARRAY to
-   GC_OPERATOR_NEW_ARRAY.  Changed GC_OPERATOR_NEW_ARRAY to be the default.
-   It can be overridden with -DGC_NO_OPERATOR_NEW_ARRAY.  (Thanks to
-   Cesar Eduardo Barros.) 
- - Changed the byte size to free-list mapping in thread local allocation
-   so that size 0 allocations are handled correctly.
- - Fixed Linux/MIPS stackbottom for new toolchain. (Thanks to Ryan Murray.)
- - Changed finalization registration to invoke GC_oom_fn when it runs out
-   of memory.
- - Removed lvalue cast in finalize.c.  This caused some debug configurations
-   not to build with some non-gcc compilers.
-
-Since 6.0alpha9:
- - Two more bug fixes for KEEP_BACK_PTRS and DBG_HDRS_ALL.
- - Fixed a stack clearing problem that resulted in SIGILL with a
-   misaligned stack pointer for multithreaded SPARC builds.
- - Integrated another HURD patch (thanks to Igor Khavkine).
-
-Since 6.0:
- - Non-debug, atomic allocations could result in bogus smashed object
-   reports with debugging on.  (Thanks to Patrick Doyle for the small
-   test case.)
- - Fixed GC_get_register_stack_base (Itanium only) to work around a glibc
-   2.2.4 bug.
- - Initial port to HP/UX on Itanium.  Thread support and both 32 and 64
-   bit ABIs appear to work.  Parallel mark support doesn't yet, due to
-   some inline assembly code issues.  Thread local allocation does appear
-   to work.
- - ifdef'ed out glibc2.1/Itanium workaround.  I suspect nobody is using
-   that combination anymore.
- - Added a patch to make new_gc_alloc.h usable with gcc3.0.  (Thanks to
-   Dimitris Vyzovitis for the patch.)
- - Debugged 64-bit support on HP/UX PA-RISC.
- - Turned on dynamic loading support for FreeBSD/ELF.  (Thanks to Peter
-   Housel.)
- - Unregistering of finalizers with debugging allocation was broken.
-   (Thanks to Jani Kajala for the test case.)
- - Old finalizers were not returned correctly from GC_debug_register_finalizer.
- - Disabled MPROTECT_VDB for Linux/M68K based on a report that it doesn't work.
- - Cleaned up some statistics gathering code in reclaim.c (Thanks to Walter
-   Bright.)
- - Added some support for OpenBSD/ELF/Linux.  (Thanks to Suzuki Toshiya.)
- - Added Jakub Jelinek's patch to use dl_iterate_phdr for dynamic library
-   traversal to dyn_load.c.  Changed it to weakly reference dl_iterate_phdr,
-   so that the old code is stilll used with old versions of glibc.
- - Cleaned up feature test macros for various threads packages and
-   integrated (partially functional) FreeBSD threads code from Loren Rittle.
-   It's likely that the cleanup broke something, since it touched lots of
-   code.  It's also likelly that it fixed some unreported bugs in the
-   less common thread implementations, since some of the original code
-   didn't stand up to close scrutiny.  Support for the next pthreads
-   implementation should be easier to add.
-
-Since 6.1alpha1:
- - No longer wrap read by default in multithreaded applications.  It was
-   pointed out on the libgcj list that this holds the allocation lock for
-   way too long if the read blocks.  For now, reads into the heap are
-   broken with incremental collection.  It's possible to turn this back on
-   if you make sure that read calls don't block (e.g. by calling select
-   first).
- - Fix ifdef in Solaris_threads.h to refer to GC_SOLARIS_THREADS.
- - Added check for environment variable GC_IGNORE_GCJ_INFO.
- - Added printing of stop-the-world GC times if GC_PRINT_STATS environment
-   variable is set.
- - The calloc definition in leak_detector.h was missing parentheses, and
-   realloc was missing a second argument to GC_REALLOC.
-   (Thanks to Elrond (elrond<at>samba-tng.org).)
- - Added GC_PRINT_BACK_HEIGHT environment variable and associated
-   code, mostly in the new file backgraph.c.  See doc/README.environment.
- - Added -DUSE_GLOBAL_ALLOC to work around a Windows NT issue.  (Thanks to
-   Jonathan Clark.)
- - Integrated port to NEC EWS4800 (MIPS-based workstation, with somewhat
-   different address-space layout). This may help for other machines with
-   holes in the data segment.  (Thanks to Hironori Sakamoto.)
- - Changed the order in which GC_push_roots and friends push things onto
-   the mark stack.  GC_push_all calls need to come first, since we can't
-   necessarily recovere if those overflow the mark stack.  (Thanks to
-   Matthew Flatt for tracking down the problem.)
- - Some minor cleanups to mostly support the Intel compiler on Linux/IA64.
-
-Since 6.1 alpha2:
- - Minor cleanup on the gcconfig.h section for SPARC.
- - Minor fix to support Intel compiler for I386/Linux. (Thanks to Sven
-   Hartrumpf.)
- - Added SPARC V9 (64-bit) support.  (Thanks to Jeff Sturm.)
- - Restructured the way in which we determine whether or not to keep
-   call stacks for debug allocation.  By default SAVE_CALL_COUNT is
-   now zero on all platforms.  Added SAVE_CALL_NARGS parameters.
-   If possible, use execinfo.h to capture call stack.  (This should
-   add support for a number of new platforms, though often at
-   considerable runtime expense.)
- - Try to print symbolic information for call stacks.  On Linux, we
-   do this with a combination of execinfo.h and running addr2line in
-   a separate process.  This is both much more expensive and much more
-   useful.  Amazingly, it seems to be fast enough for most purposes.
- - Redefined strdup if -DREDIRECT_MALLOC is given.
- - Changed incremental collector and MPROTECT_VDB implementation so that,
-   under favorable conditions, pointerfree objects are not protected.
-   Added GC_incremental_protection_needs() to determine ahead of time whether
-   pointerfree objects may be protected.  Replaced GC_write_hint() with
-   GC_remove_protection().
- - Added test for GC_ENABLE_INCREMENTAL environment variable.
- - Made GC_time_limit runtime configurable.  Added GC_PAUSE_TIME_TARGET
-   environment variable.
- - Eliminated GC_page_sz, a duplicate of GC_page_size.
- - Caused the Solaris and Irix thread creation primitives to call
-   GC_init_inner().
- 
-Since 6.1alpha3:
- - Fixed typo in sparc_mach_dep.S, preventing the 64-bit version from
-   building.  Increased 64-bit heap size limit in test.c slightly, since
-   a functional SPARC collector seems to slightly exceed the old limits.
-   (Thanks again to Jeff Sturm.)
- - Use NPRGREG in solaris_threads.c, thus printing all registers if things
-   go wrong.
- - Added GC_MARKERS environment variable to allow use of a single marker
-   thread on an MP without confusing the lock implementation.
- - Collect much less aggressively in incremental mode with GC_TIME_UNLIMITED.
-   This is really a purely generational mode, and we can afford to 
-   postpone the collection until the heap is (nearly) full.
- - Remove read() wrapper for MPROTECT_VDB.  It was causing more harm than
-   good.  It is often no longer needed if system calls avoid writing to
-   pointerfull heap objects.
- - Fix MACOSX test in gcconfig.h. (Thanks to John Clements.)
- - Change GC_test_and_set so that it consistently has one argument.
-   Add spaces to ::: in powerpc assembly code in gc_locks.h.
-   (Thanks to Ryan Murray.)
- - Fixed a formatting error in dbg_mlc.c.  Added prototype to GC_abort()
-   declaration.   (Thanks to Michael Smith.)
- - Removed "source" argument to GC_find_start().  Eliminate GC_FIND_START().
- - Added win32 recognition code in configure.in.  Changed some of the
-   dllimport/export defines in gc.h.  (Thanks to Adam Megacz.)
- - GC_malloc_many didn't set hb_last_reclaimed when it called 
-   GC_reclaim_generic.  (I'm not sure this matters much, but ...)
- - Allocating uncollectable objects with debug information sometimes
-   allocated objects that were one byte too small, since uncollectable
-   objects don't have the extra byte added at the end.  (Thanks to
-   Wink Saville for pointing this out.)
- - Added a bit more assertion checking to make sure that gcj objects
-   on free lists never have a nonzero second word.
- - Replaced BCC_MAKEFILE with an up-to-date one.  (Thanks to 
-   Andre Leiradella.)
- - Upgraded libtool, cinfigure.in and some related files to hopefully
-   support NetBSD/SPARC.  (Thanks to Adrian Bunk.)  Unfortunately,
-   libtool 1.4.2 seemed to be buggy due to missing quotes in several
-   "test" invocations.  Fixed those in the ltmain.sh script.
- - Some win32-specific patches, including the introduction of
-   GC_CreateThread.  (Thanks to Adam Megacz.)
- - Merged in gcj changes from Anthony Green to support embedded systems.
- - Tried to consistently rename preprocessed assembly files with a capital
-   .S extension.
- - Use alpha_mach_dep.S on ALPHA again.  It doesn't really matter, but this
-   makes our distribution consistent with the gcc one, avoiding future merge
-   problems.
- - Move GET_MEM definition into gcconfig.h.  Include gcconfig.h slightly
-   later in gc_priv.h to avoid forward references to ptr_t.
- - Add some testing of local allocation to test.c.
- - Change definition of INVALID_QTID in specific.h.  The -1 value was used
-   inconsistently, and too likely to collide with a valid stack address.
-   Some general clean-up of specific.[ch].  Added assertions.  (Thanks
-   to Michael Smith for tracking down an intermittent bug to this
-   general area.  I'm not sure it has been squashed yet, however.)
- - On Pthread systems it was not safe to call GC_malloc() between fork()
-   and exec().  According to the applicable standards, it doesn't appear
-   to be safe to call malloc() or many other libc functions either, thus
-   it's not clear this is fixable.  Added experimental support for
-   -DHANDLE_FORK in linux_threads.c which tries to support it.  It may
-   succeed if libc does the right thing.  I'm not sure whether it does.
-   (Thanks to Kenneth Schalk for pointing out this issue.)
- - Documented thread local allocation primitives to require an
-   explicit GC_init call.  GC_init_parallel is no longer declared to
-   be a constructor function, since that isn't portable and often
-   seems to lead to initialization order problems.
- - Changed gc_cpp.cc and gc_cpp.h in one more attempt to make them
-   compatible with Visual C++ 6.  (Thanks to Wink Saville for the
-   patch.)
- - Some more patches for Linux on HP PA-RISC.
- - Added include/gc_allocator.h.  It implements (hopefully) standard
-   conforming (as opposed to SGI-style) allocators that allocate
-   collectable (gc_allocator) or GC-traceable, but not collectable
-   (traceable_allocator) objects.  This borrows heavily from libstc++,
-   which borrows heavily from the SGI implementation, this part of
-   which was written by Matt Austern.  Changed test_cpp.cc to very
-   minimally test this.
- - On Linux/X86, retry mmap with a different start argument.  That should
-   allow the collector to use more (closer to 3GB) of the address space.
-   (Thanks to Jeffrey Mark Siskind for tracking this down.)
- - Force 64 bit alignment with GCJ support.  (Reflects Bryce McKinley's
-   patch to the gcc tree.)
- - Refined the choice of sa_handler vs. sa_sigaction in GC_dirty_init
-   to accomodate some glibc5 systems.  (Thanks to Dan Fandrich for the
-   patch.)
- - Compensated for the fact that current versions of glibc set
-   __libc_stack_end incorrectly on Linux/IA64 while initialization code
-   is running.  This could cause the collector to miss 16 bytes of
-   the memory stack if GC_malloc or friends where called before main().
- - Mostly integrated Takis Psarogiannakopoulos' port to DG/UX Inix 86.
-   This will probably take another iteration to work, since his
-   patch conflicted with the libtool upgrade. 
- - Added README.arm.cross containing some information about cross-
-   compiling to an ARM processor from Margaret Fleck.
-
-Since 6.1alpha4:
- - Added GC_finalizer_mem_freed, and changed some of the code that
-   decided on heap expansion to look at it.  Memory explicitly
-   deallocated by finalizers essentially needs to be counted as reclaimed
-   by the GC.  Otherwise there are cases in which the heap can grow
-   unboundedly.  (Thanks to Mark Reichert for the test case.)
- - Integrated Adam Megacz patches to not scan dynamic libraries if
-   we are compiling with gcc on win32.  Otherwise we need structured
-   exception handling to deal with asynchronously unmapped root
-   segments, and gcc doesn't directly support that.
- - Integrated Anthony Green's patch to support Wine.
- - GC_OPERATOR_NEW_ARRAY was misspelled OPERATOR_NEW_ARRAY in several
-   places, including gc_cpp.cc.  (Thanks to Wink Saville for pointing
-   this out.)
- - Integrated Loren James Rittle's Alpha FreeBSD patches.  In
-   response to Richard Henderson's suggestion, these also
-   changed the declarations of symbols like _end on many platforms to
-   that they wouldn't mistakenly be declared as short data symbols.
- - Integrated changes from the Debian distribution.  (Thanks to Ryan Murray
-   for pointing these out.)  Fix C++ comments in POWERPC port.  Add ARM32
-   incremental GC support.  Get rid of USE_GENERIC_PUSH_REGS for alpha/Linux,
-   this time for real.  Use va_copy to get rid of cord printf problems
-   (finally).
- - Close file descriptor used to count cpus.  Thanks to Jeff Sturm for
-   pointing out the omission.
- - Don't just drop gcj free lists in GC_start_reclaim, since that can
-   eventually cause the marker to see a bogus mark descriptor in the 
-   dropped objects.  The usual symptom was a very intermittent segmentation
-   fault in the marker.  This mattered only if one of the GC_gcj_malloc
-   variants was used.  (Thanks to Michael Smith, Jeff Sturm, Bryce
-   McKinley and Tom Tromey for helping to track this down.)
- - Fixed Linux and Solaris/64 SPARC configuration.  (Thanks to David Miller,
-   Jeff Sturm, Tom Tromey, and Christian Joensson.)
- - Fixed a typo in strdup definition.  (Thanks to Gerard A Allan.)
- - Changed Makefile.direct to invoke $(CC) to assemble alpha_mach_dep.S.
-   This is needed on Linux.  I'm not sure whether it's better or worse
-   on Tru64.
- - Changed gc_cpp.h once more to declare operator new and friends only in
-   a Microsoft environment.  This may need further fine tuning.  (Thanks to
-   Johannes Schmidt for pointing out that the older code breaks on gcc3.0.4.)
- - Don't ever override strdup if it's already macro defined.  (Thanks to
-   Adnan Ali for pointing out the problem.)
- - Changed gc_cpp.h yet again to also overload placement new.  Due to the
-   C++ overloading rules, the other overloaded new operations otherwise hide
-   placement new, which causes many STL uses to break.  (Thanks to Reza
-   Shahidi for reporting this, and to Matt Austern for proposing a fix.)
- - Integrated cygwin pthreads support from Dan Bonachea.
- - Turn on DYNAMIC_LOADING for NetBSD.  (Thanks to Krister Walfridsson.)
- - Changed printing code to print more complete GC times.
- - Applied Mark Mitchell's Irix patch to correct some bitrot.
- - Clarified which object-printing routines in dbg_mlc.c should hold
-   the allocation lock.  Restructured the code to allow reasonable object
-   printing with -DREDIRECT_MALLOC.
- - Fix the Linux mmap code to always start with 0x1000 as the initial hint.
-   Minor patches for 64-bit AIX, particularly to STACKBOTTOM.
-   (Thanks again to Jeffrey Mark Siskind.)
- - Renamed "SUSPENDED" flag for Solaris threads support to avoid a conflict
-   with a system header. (Thanks to Philp Brown.)
- 
-
-To do:
- - --enable-redirect-malloc is mostly untested and known not to work
-   on some platforms. 
- - The win32 collector ends up tracing some (most?) objects allocated with
-   the system allocator, in spite if the fact that it tries not to.
-   This costs time and space, though it remains correct.
-   We need a way to identify memory regions used by the system malloc(),
-   or an alternate way to locate dll data areas.  A very partial
-   workaround is to use GC_malloc_atomic_uncollectable() instead of
-   the system malloc() for most allocation.
- - There seem to be outstanding issues on Solaris/X86, possibly with
-   finding the data segment starting address.  Information/patches would
-   be appreciated.
- - Very large root set sizes (> 16 MB or so) could cause the collector
-   to abort with an unexpected mark stack overflow.  (Thanks again to
-   Peter Chubb.)  NOT YET FIXED.  Workaround is to increase the initial
-   size.
- - The SGI version of the collector marks from mmapped pages, even
-   if they are not part of dynamic library static data areas.  This
-   causes performance problems with some SGI libraries that use mmap
-   as a bitmap allocator.  NOT YET FIXED.  It may be possible to turn
-   off DYNAMIC_LOADING in the collector as a workaround.  It may also
-   be possible to conditionally intercept mmap and use GC_exclude_static_roots.
-   The real fix is to walk rld data structures, which looks possible.
- - Incremental collector should handle large objects better.  Currently,
-   it looks like the whole object is treated as dirty if any part of it
-   is.
- 
diff --git a/gc/doc/README.contributors b/gc/doc/README.contributors
deleted file mode 100644
index fd5c95f..0000000
--- a/gc/doc/README.contributors
+++ /dev/null
@@ -1,57 +0,0 @@
-This is an attempt to acknowledge early contributions to the garbage
-collector.  Later contributions should instead be mentioned in
-README.changes.
-
-HISTORY -
-
-  Early versions of this collector were developed as a part of research
-projects supported in part by the National Science Foundation
-and the Defense Advance Research Projects Agency.
-
-The garbage collector originated as part of the run-time system for
-the Russell programming language implementation. The first version of the
-garbage collector was written primarily by Al Demers.  It was then refined
-and mostly rewritten, primarily by Hans-J. Boehm, at Cornell U., 
-the University of Washington, Rice University (where it was first used for
-C and assembly code), Xerox PARC, SGI, and HP Labs.  However, significant
-contributions have also been made by many others.
-
-Some other contributors:  
-
-More recent contributors are mentioned in the modification history in
-README.changes.  My apologies for any omissions.
-
-The SPARC specific code was originally contributed by Mark Weiser.
-The Encore Multimax modifications were supplied by
-Kevin Kenny (kenny@m.cs.uiuc.edu).  The adaptation to the IBM PC/RT is largely
-due to Vernon Lee, on machines made available to Rice by IBM.
-Much of the HP specific code and a number of good suggestions for improving the
-generic code are due to Walter Underwood.
-Robert Brazile (brazile@diamond.bbn.com) originally supplied the ULTRIX code.
-Al Dosser (dosser@src.dec.com) and Regis Cridlig (Regis.Cridlig@cl.cam.ac.uk)
-subsequently provided updates and information on variation between ULTRIX
-systems.  Parag Patel (parag@netcom.com) supplied the A/UX code.
-Jesper Peterson(jep@mtiame.mtia.oz.au), Michel Schinz, and
-Martin Tauchmann (martintauchmann@bigfoot.com) supplied the Amiga port.
-Thomas Funke (thf@zelator.in-berlin.de(?)) and
-Brian D.Carlstrom (bdc@clark.lcs.mit.edu) supplied the NeXT ports.
-Douglas Steel (doug@wg.icl.co.uk) provided ICL DRS6000 code.
-Bill Janssen (janssen@parc.xerox.com) supplied the SunOS dynamic loader
-specific code. Manuel Serrano (serrano@cornas.inria.fr) supplied linux and
-Sony News specific code.  Al Dosser provided Alpha/OSF/1 code.  He and
-Dave Detlefs(detlefs@src.dec.com) also provided several generic bug fixes.
-Alistair G. Crooks(agc@uts.amdahl.com) supplied the NetBSD and 386BSD ports.
-Jeffrey Hsu (hsu@soda.berkeley.edu) provided the FreeBSD port.
-Brent Benson (brent@jade.ssd.csd.harris.com) ported the collector to
-a Motorola 88K processor running CX/UX (Harris NightHawk).
-Ari Huttunen (Ari.Huttunen@hut.fi) generalized the OS/2 port to
-nonIBM development environments (a nontrivial task).
-Patrick Beard (beard@cs.ucdavis.edu) provided the initial MacOS port.
-David Chase, then at Olivetti Research, suggested several improvements.
-Scott Schwartz (schwartz@groucho.cse.psu.edu) supplied some of the
-code to save and print call stacks for leak detection on a SPARC.
-Jesse Hull and John Ellis supplied the C++ interface code.
-Zhong Shao performed much of the experimentation that led to the
-current typed allocation facility.  (His dynamic type inference code hasn't
-made it into the released version of the collector, yet.)
-
diff --git a/gc/doc/README.cords b/gc/doc/README.cords
deleted file mode 100644
index 3485e01..0000000
--- a/gc/doc/README.cords
+++ /dev/null
@@ -1,53 +0,0 @@
-Copyright (c) 1993-1994 by Xerox Corporation.  All rights reserved.
-
-THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
-OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
-
-Permission is hereby granted to use or copy this program
-for any purpose,  provided the above notices are retained on all copies.
-Permission to modify the code and to distribute modified code is granted,
-provided the above notices are retained, and a notice that the code was
-modified is included with the above copyright notice.
-
-Please send bug reports to Hans-J. Boehm (Hans_Boehm@hp.com or
-boehm@acm.org).
-
-This is a string packages that uses a tree-based representation.
-See cord.h for a description of the functions provided.  Ec.h describes
-"extensible cords", which are essentially output streams that write
-to a cord.  These allow for efficient construction of cords without
-requiring a bound on the size of a cord.
-
-More details on the data structure can be found in
-
-Boehm, Atkinson, and Plass, "Ropes: An Alternative to Strings",
-Software Practice and Experience 25, 12, December 1995, pp. 1315-1330.
-
-A fundamentally similar "rope" data structure is also part of SGI's standard
-template library implementation, and its descendents, which include the
-GNU C++ library.  That uses reference counting by default.
-There is a short description of that data structure at
-http://reality.sgi.com/boehm/ropeimpl.html .  (The more official location
-http://www.sgi.com/tech/stl/ropeimpl.html is missing a figure.)
-
-All of these are descendents of the "ropes" in Xerox Cedar.
-
-de.c is a very dumb text editor that illustrates the use of cords.
-It maintains a list of file versions.  Each version is simply a
-cord representing the file contents.  Nonetheless, standard
-editing operations are efficient, even on very large files.
-(Its 3 line "user manual" can be obtained by invoking it without
-arguments.  Note that ^R^N and ^R^P move the cursor by
-almost a screen.  It does not understand tabs, which will show
-up as highlighred "I"s.  Use the UNIX "expand" program first.)
-To build the editor, type "make cord/de" in the gc directory.
-
-This package assumes an ANSI C compiler such as gcc.  It will
-not compile with an old-style K&R compiler.
-
-Note that CORD_printf iand friends use C functions with variable numbers
-of arguments in non-standard-conforming ways.  This code is known to
-break on some platforms, notably PowerPC.  It should be possible to
-build the remainder of the library (everything but cordprnt.c) on
-any platform that supports the collector.
- 
diff --git a/gc/doc/README.dj b/gc/doc/README.dj
deleted file mode 100644
index 613bc42..0000000
--- a/gc/doc/README.dj
+++ /dev/null
@@ -1,12 +0,0 @@
-[Original version supplied by Xiaokun Zhu <xiaokun@aero.gla.ac.uk>]
-[This version came mostly from Gary Leavens.			  ]
-
-Look first at Makefile.dj, and possibly change the definitions of
-RM and MV if you don't have rm and mv installed.
-Then use Makefile.dj to compile the garbage collector.
-For example, you can do:
-
-	make -f Makefile.dj test
-
-All the tests should work fine.
-
diff --git a/gc/doc/README.environment b/gc/doc/README.environment
deleted file mode 100644
index dc17209..0000000
--- a/gc/doc/README.environment
+++ /dev/null
@@ -1,101 +0,0 @@
-The garbage collector looks at a number of environment variables which are
-then used to affect its operation.  These are examined only on Un*x-like
-platforms.
-
-GC_INITIAL_HEAP_SIZE=<bytes> -	Initial heap size in bytes.  May speed up
-				process start-up.
-
-GC_LOOP_ON_ABORT - Causes the collector abort routine to enter a tight loop.
-		   This may make it easier to debug, such a process, especially
-		   for multithreaded platforms that don't produce usable core
-		   files, or if a core file would be too large.  On some
-		   platforms, this also causes SIGSEGV to be caught and
-		   result in an infinite loop in a handler, allowing
-		   similar debugging techniques.
-
-GC_PRINT_STATS - Turn on as much logging as is easily feasible without
-		 adding signifcant runtime overhead.  Doesn't work if
-		 the collector is built with SMALL_CONFIG.  Overridden
-		 by setting GC_quiet.  On by default if the collector
-		 was built without -DSILENT.
-
-GC_PRINT_ADDRESS_MAP - Linux only.  Dump /proc/self/maps, i.e. various address
-		       maps for the process, to stderr on every GC.  Useful for
-		       mapping root addresses to source for deciphering leak
-		       reports.
-
-GC_NPROCS=<n> - Linux w/threads only.  Explicitly sets the number of processors
-	        that the GC should expect to use.  Note that setting this to 1
-		when multiple processors are available will preserve
-		correctness, but may lead to really horrible performance,
-		since the lock implementation will immediately yield without
-		first spinning.
-
-GC_MARKERS=<n> - Linux w/threads and parallel marker only.  Set the number
-		of marker threads.  This is normaly set to the number of
-		processors.  It is safer to adjust GC_MARKERS than GC_NPROCS,
-		since GC_MARKERS has no impact on the lock implementation.
-
-GC_NO_BLACKLIST_WARNING - Prevents the collector from issuing
-		warnings about allocations of very large blocks.
-		Deprecated.  Use GC_LARGE_ALLOC_WARN_INTERVAL instead.
-
-GC_LARGE_ALLOC_WARN_INTERVAL=<n> - Print every nth warning about very large
-		block allocations, starting with the nth one.  Small values
-		of n are generally benign, in that a bounded number of
-		such warnings generally indicate at most a bounded leak.
-		For best results it should be set at 1 during testing.
-		Default is 5.  Very large numbers effectively disable the
-		warning.
-
-GC_IGNORE_GCJ_INFO - Ignore the type descriptors implicitly supplied by
-		     GC_gcj_malloc and friends.  This is useful for debugging
-		     descriptor generation problems, and possibly for
-		     temporarily working around such problems.  It forces a
-		     fully conservative scan of all heap objects except
-		     those known to be pointerfree, and may thus have other
-		     adverse effects.
-
-GC_PRINT_BACK_HEIGHT - Print max length of chain through unreachable objects
-		     ending in a reachable one.  If this number remains
-		     bounded, then the program is "GC robust".  This ensures
-		     that a fixed number of misidentified pointers can only
-		     result in a bounded space leak.  This currently only
-		     works if debugging allocation is used throughout.
-		     It increases GC space and time requirements appreciably.
-		     This feature is still somewhat experimental, and requires
-		     that the collector have been built with MAKE_BACK_GRAPH
-		     defined.  For details, see Boehm, "Bounding Space Usage
-		     of Conservative Garbage Collectors", POPL 2001, or
-		     http://lib.hpl.hp.com/techpubs/2001/HPL-2001-251.html .
-
-The following turn on runtime flags that are also program settable.  Checked
-only during initialization.  We expect that they will usually be set through
-other means, but this may help with debugging and testing:
-
-GC_ENABLE_INCREMENTAL - Turn on incremental collection at startup.  Note that,
-		     depending on platform and collector configuration, this
-		     may involve write protecting pieces of the heap to
-		     track modifications.  These pieces may include pointerfree
-		     objects or not.  Although this is intended to be
-		     transparent, it may cause unintended system call failures.
-		     Use with caution.
-
-GC_PAUSE_TIME_TARGET - Set the desired garbage collector pause time in msecs.
-		     This only has an effect if incremental collection is
-		     enabled.  If a collection requires appreciably more time
-		     than this, the client will be restarted, and the collector
-		     will need to do additional work to compensate.  The
-		     special value "999999" indicates that pause time is
-		     unlimited, and the incremental collector will behave
-		     completely like a simple generational collector.  If
-		     the collector is configured for parallel marking, and
-		     run on a multiprocessor, incremental collection should
-		     only be used with unlimited pause time.
-
-GC_FIND_LEAK - Turns on GC_find_leak and thus leak detection.
-
-GC_ALL_INTERIOR_POINTERS - Turns on GC_all_interior_pointers and thus interior
-			   pointer recognition.
-
-GC_DONT_GC - Turns off garbage collection.  Use cautiously.
diff --git a/gc/doc/README.ews4800 b/gc/doc/README.ews4800
deleted file mode 100644
index 80bca2b..0000000
--- a/gc/doc/README.ews4800
+++ /dev/null
@@ -1,81 +0,0 @@
-GC on EWS4800
--------------
-
-1. About EWS4800
-   EWS4800 is 32bit/64bit workstation.
-
-     Vender: NEC Corporation
-     OS: UX/4800 R9.* - R13.* (SystemV R4.2)
-     CPU: R4000, R4400, R10000 (MIPS)
-
-2. Compiler
-
- 32bit:
-   Use ANSI C compiler.
-     CC = /usr/abiccs/bin/cc
-
- 64bit:
-   Use 64bit ANSI C compiler.
-     CC = /usr/ccs64/bin/cc
-     AR = /usr/ccs64/bin/ar
-
-3. ELF file format
-   *** Caution: The following infomation is empirical. ***
-
- 32bit:
-   ELF file has an unique format. (See a.out(4) and end(3C).)
-
-     &_start
-        :      text segment
-     &etext
-     DATASTART
-        :      data segment (initialized)
-     &edata
-     DATASTART2
-        :      data segment (uninitialized)
-     &end
-
-   Here, DATASTART and DATASTART2 are macros of GC, and are defined as
-   the following equations. (See include/private/gcconfig.h.)
-   The algorithm for DATASTART is similar with the function
-   GC_SysVGetDataStart() in os_dep.c.
-
-     DATASTART  = ((&etext + 0x3ffff) & ~0x3ffff) + (&etext & 0xffff)
-
-    Dynamically linked:
-     DATASTART2 = (&_gp + 0x8000 + 0x3ffff) & ~0x3ffff
-
-    Statically linked:
-     DATASTART2 = &edata
-
-   GC has to check addresses both between DATASTART and &edata, and
-   between DATASTART2 and &end. If a program accesses between &etext
-   and DATASTART, or between &edata and DATASTART2, the segmentation
-   error occurs and the program stops.
-
-   If a program is statically linked, there is not a gap between
-   &edata and DATASTART2. The global symbol &_DYNAMIC_LINKING is used
-   for the detection.
-
- 64bit:
-   ELF file has a simple format. (See end(3C).)
-
-     _ftext
-        :      text segment
-     _etext
-     _fdata = DATASTART
-        :      data segment (initialized)
-     _edata
-     _fbss
-        :      data segment (uninitialized)
-     _end = DATAEND
-
---
-Hironori SAKAMOTO <hsaka@mth.biglobe.ne.jp>
-
-
-When using the new "configure; make" build process, please
-run configure with the --disable-shared option.  "Make check" does not
-yet pass with dynamic libraries.  Ther reasons for that are not yet
-understood.  (HB, paraphrasing message from Hironori SAKAMOTO.)
-
diff --git a/gc/doc/README.hp b/gc/doc/README.hp
deleted file mode 100644
index caa8bdd..0000000
--- a/gc/doc/README.hp
+++ /dev/null
@@ -1,18 +0,0 @@
-Dynamic loading support requires that executables be linked with -ldld.
-The alternative is to build the collector without defining DYNAMIC_LOADING
-in gcconfig.h and ensuring that all garbage collectable objects are
-accessible without considering statically allocated variables in dynamic
-libraries.
-
-The collector should compile with either plain cc or cc -Ae.  Cc -Aa
-fails to define _HPUX_SOURCE and thus will not configure the collector
-correctly.
-
-Incremental collection support was reccently added, and should now work.
-
-In spite of past claims, pthread support under HP/UX 11 should now work.
-Define GC_HPUX_THREADS for the build.  Incremental collection still does not
-work in combination with it.
-
-The stack finding code can be confused by putenv calls before collector
-initialization.  Call GC_malloc or GC_init before any putenv calls.
diff --git a/gc/doc/README.linux b/gc/doc/README.linux
deleted file mode 100644
index efd0a26..0000000
--- a/gc/doc/README.linux
+++ /dev/null
@@ -1,135 +0,0 @@
-See README.alpha for Linux on DEC AXP info.
-
-This file applies mostly to Linux/Intel IA32.  Ports to Linux on an M68K
-and PowerPC are also integrated.  They should behave similarly, except that
-the PowerPC port lacks incremental GC support, and it is unknown to what
-extent the Linux threads code is functional.  See below for M68K specific
-notes.
-
-Incremental GC is supported on Intel IA32 and M68K.
-
-Dynamic libraries are supported on an ELF system.  A static executable
-should be linked with the gcc option "-Wl,-defsym,_DYNAMIC=0".
-
-The collector appears to work with Linux threads.  We have seen
-intermittent hangs in sem_wait.  So far we have been unable to reproduce
-these unless the process was being debugged or traced.  Thus it's
-possible that the only real issue is that the debugger loses
-signals on rare occasions.
-
-The garbage collector uses SIGPWR and SIGXCPU if it is used with
-Linux threads.  These should not be touched by the client program.
-
-To use threads, you need to abide by the following requirements:
-
-1) You need to use LinuxThreads (which are included in libc6).
-
-   The collector relies on some implementation details of the LinuxThreads
-   package.  It is unlikely that this code will work on other
-   pthread implementations (in particular it will *not* work with
-   MIT pthreads).
-
-2) You must compile the collector with -DGC_LINUX_THREADS and -D_REENTRANT
-   specified in the Makefile.
-
-3a) Every file that makes thread calls should define GC_LINUX_THREADS and 
-   _REENTRANT and then include gc.h.  Gc.h redefines some of the
-   pthread primitives as macros which also provide the collector with
-   information it requires.
-
-3b) A new alternative to (3a) is to build the collector and compile GC clients
-   with -DGC_USE_LD_WRAP, and to link the final program with
-
-   (for ld) --wrap read --wrap dlopen --wrap pthread_create \
-	    --wrap pthread_join --wrap pthread_detach \
-	    --wrap pthread_sigmask --wrap sleep
-
-   (for gcc) -Wl,--wrap -Wl,read -Wl,--wrap -Wl,dlopen -Wl,--wrap \
-	     -Wl,pthread_create -Wl,--wrap -Wl,pthread_join -Wl,--wrap \
-	     -Wl,pthread_detach -Wl,--wrap -Wl,pthread_sigmask \
-	     -Wl,--wrap -Wl,sleep
-
-   In any case, _REENTRANT should be defined during compilation.
-
-4) Dlopen() disables collection during its execution.  (It can't run
-   concurrently with the collector, since the collector looks at its
-   data structures.  It can't acquire the allocator lock, since arbitrary
-   user startup code may run as part of dlopen().)  Under unusual
-   conditions, this may cause unexpected heap growth.
-
-5) The combination of GC_LINUX_THREADS, REDIRECT_MALLOC, and incremental
-   collection fails in seemingly random places.  This hasn't been tracked
-   down yet, but is perhaps not completely astonishing.  The thread package
-   uses malloc, and thus can presumably get SIGSEGVs while inside the
-   package.  There is no real guarantee that signals are handled properly
-   at that point.
-
-6) Thread local storage may not be viewed as part of the root set by the
-   collector.  This probably depends on the linuxthreads version.  For the
-   time being, any collectable memory referenced by thread local storage should
-   also be referenced from elsewhere, or be allocated as uncollectable.
-   (This is really a bug that should be fixed somehow.)
-
-
-M68K LINUX:
-(From Richard Zidlicky)
-The bad news is that it can crash every linux-m68k kernel on a 68040,
-so an additional test is needed somewhere on startup. I have meanwhile
-patches to correct the problem in 68040 buserror handler but it is not
-yet in any standard kernel.
-
-Here is a simple test program to detect whether the kernel has the
-problem. It could be run as a separate check in configure or tested 
-upon startup. If it fails (return !0) than mprotect can't be used
-on that system.
-
-/*
- * test for bug that may crash 68040 based Linux
- */
-
-#include <sys/mman.h>
-#include <signal.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-
-char *membase;
-int pagesize=4096;
-int pageshift=12;
-int x_taken=0;
-
-int sighandler(int sig)
-{
-   mprotect(membase,pagesize,PROT_READ|PROT_WRITE);
-   x_taken=1;
-}
-
-main()
-{
-  long l;
-
-   signal(SIGSEGV,sighandler);
-   l=(long)mmap(NULL,pagesize,PROT_READ,MAP_PRIVATE | MAP_ANON,-1,0);
-  if (l==-1)
-     {
-       perror("mmap/malloc");
-       abort();
-     }
-  membase=(char*)l;
-    *(long*)(membase+sizeof(long))=123456789;
-  if (*(long*)(membase+sizeof(long)) != 123456789 )
-    {
-      fprintf(stderr,"writeback failed !\n");
-      exit(1);
-    }
-  if (!x_taken)
-    {
-      fprintf(stderr,"exception not taken !\n");
-      exit(1);
-    }
-  fprintf(stderr,"vmtest Ok\n");
-  exit(0);
-}
-
-
diff --git a/gc/doc/README.macros b/gc/doc/README.macros
deleted file mode 100644
index d9df8dd..0000000
--- a/gc/doc/README.macros
+++ /dev/null
@@ -1,78 +0,0 @@
-The collector uses a large amount of conditional compilation in order to
-deal with platform dependencies.  This violates a number of known coding
-standards.  On the other hand, it seems to be the only practical way to
-support this many platforms without excessive code duplication. 
-
-A few guidelines have mostly been followed in order to keep this manageable:
-
-1) #if and #ifdef directives are properly indented whenever easily possible.
-All known C compilers allow whitespace between the "#" and the "if" to make
-this possible.  ANSI C also allows white space before the "#", though we
-avoid that.  It has the known disadvantages that it differs from the normal
-GNU conventions, and that it makes patches larger than otherwise necessary.
-In my opinion, it's still well worth it, for the same reason that we indent
-ordinary "if" statements.
-
-2) Whenever possible, tests are performed on the macros defined in gcconfig.h
-instead of directly testing patform-specific predefined macros.  This makes it
-relatively easy to adapt to new compilers with a different set of predefined
-macros.  Currently these macros generally identify platforms instead of
-features.  In many cases, this is a mistake.
-
-3) The code currently avoids #elif, eventhough that would make it more
-readable.  This was done since #elif would need to be understood by ALL
-compilers used to build the collector, and that hasn't always been the case.
-It makes sense to reconsider this decision at some point, since #elif has been
-standardized at least since 1989.
-
-Many of the tested configuration macros are at least somewhat defined in
-either include/private/gcconfig.h or in Makefile.direct.  Here is an attempt
-at defining some of the remainder:  (Thanks to Walter Bright for suggesting
-this.  This is a work in progress)
-
-MACRO		EXPLANATION
------		-----------
-
-__DMC__	Always #define'd by the Digital Mars compiler. Expands
-		to the compiler version number in hex, i.e. 0x810 is
-		version 8.1b0
-
-_ENABLE_ARRAYNEW
-		#define'd by the Digital Mars C++ compiler when
-		operator new[] and delete[] are separately
-		overloadable. Used in gc_cpp.h.
-
-_MSC_VER	Expands to the Visual C++ compiler version.  Assumed to
-		not be defined for other compilers (at least if they behave
-		appreciably differently).
-
-_DLL		Defined by Visual C++ if dynamic libraries are being built
-		or used.  Used to test whether __declspec(dllimport) or
-		__declspec(dllexport) needs to be added to declarations
-		to support the case in which the collector is in a dll.
-
-GC_DLL		User-settable macro that forces the effect of _DLL.
-
-GC_NOT_DLL	User-settable macro that overrides _DLL, e.g. if dynamic
-		libraries are used, but the collector is in a static library.
-
-__STDC__	Assumed to be defined only by compilers that understand
-		prototypes and other C89 features.  Its value is generally
-		not used, since we are fine with most nonconforming extensions.
-
-SUNOS5SIGS	Solaris-like signal handling.  This is probably misnamed,
-		since it really doesn't guarantee much more than Posix.
-		Currently set only for Solaris2.X, HPUX, and DRSNX.  Should
-		probably be set for some other platforms.
-
-PCR		Set if the collector is being built as part of the Xerox
-		Portable Common Runtime.
-
-SRC_M3		Set if the collector is being built as a replacement of the
-		one in the DEC/Compaq SRC Modula-3 runtime.  I suspect this
-		was last used around 1994, and no doubt broke a long time ago.
-		It's there primarily incase someone wants to port to a similar
-		system.
-
-
-
diff --git a/gc/doc/README.rs6000 b/gc/doc/README.rs6000
deleted file mode 100644
index f5630b2..0000000
--- a/gc/doc/README.rs6000
+++ /dev/null
@@ -1,9 +0,0 @@
-We have so far failed to find a good way to determine the stack base.
-It is highly recommended that GC_stackbottom be set explicitly on program
-startup.  The supplied value sometimes causes failure under AIX 4.1, though
-it appears to work under 3.X.  HEURISTIC2 seems to work under 4.1, but
-involves a substantial performance penalty, and will fail if there is
-no limit on stack size.
-
-There is no thread support.  (I assume recent versions of AIX provide
-pthreads?  I no longer have access to a machine ...)
diff --git a/gc/doc/README.sgi b/gc/doc/README.sgi
deleted file mode 100644
index 7bdb50a..0000000
--- a/gc/doc/README.sgi
+++ /dev/null
@@ -1,41 +0,0 @@
-Performance of the incremental collector can be greatly enhanced with
--DNO_EXECUTE_PERMISSION.
-
-The collector should run with all of the -32, -n32 and -64 ABIs.  Remember to
-define the AS macro in the Makefile to be "as -64", or "as -n32".
-
-If you use -DREDIRECT_MALLOC=GC_malloc with C++ code, your code should make
-at least one explicit call to malloc instead of new to ensure that the proper
-version of malloc is linked in.
-
-Sproc threads are not supported in this version, though there may exist other
-ports.
-
-Pthreads support is provided.  This requires that:
-
-1) You compile the collector with -DGC_IRIX_THREADS specified in the Makefile.
-
-2) You have the latest pthreads patches installed.  
-
-(Though the collector makes only documented pthread calls,
-it relies on signal/threads interactions working just right in ways
-that are not required by the standard.  It is unlikely that this code
-will run on other pthreads platforms.  But please tell me if it does.)
-
-3) Every file that makes thread calls should define IRIX_THREADS and then
-include gc.h.  Gc.h redefines some of the pthread primitives as macros which
-also provide the collector with information it requires.
-
-4) pthread_cond_wait and pthread_cond_timed_wait should be prepared for
-premature wakeups.  (I believe the pthreads and realted standards require this
-anyway.  Irix pthreads often terminate a wait if a signal arrives.
-The garbage collector uses signals to stop threads.)
-
-5) It is expensive to stop a thread waiting in IO at the time the request is
-initiated.  Applications with many such threads may not exhibit acceptable
-performance with the collector.  (Increasing the heap size may help.)
-
-6) The collector should not be compiled with -DREDIRECT_MALLOC.  This
-confuses some library calls made by the pthreads implementation, which
-expect the standard malloc.
-
diff --git a/gc/doc/README.solaris2 b/gc/doc/README.solaris2
deleted file mode 100644
index 6ed61dc..0000000
--- a/gc/doc/README.solaris2
+++ /dev/null
@@ -1,62 +0,0 @@
-The collector supports both incremental collection and threads under
-Solaris 2.  The incremental collector normally retrieves page dirty information
-through the appropriate /proc calls.  But it can also be configured
-(by defining MPROTECT_VDB instead of PROC_VDB in gcconfig.h) to use mprotect
-and signals.  This may result in shorter pause times, but it is no longer
-safe to issue arbitrary system calls that write to the heap.
-
-Under other UNIX versions,
-the collector normally obtains memory through sbrk.  There is some reason
-to expect that this is not safe if the client program also calls the system
-malloc, or especially realloc.  The sbrk man page strongly suggests this is
-not safe: "Many library routines use malloc() internally, so use brk()
-and sbrk() only when you know  that malloc() definitely will not be used by
-any library routine."  This doesn't make a lot of sense to me, since there
-seems to be no documentation as to which routines can transitively call malloc.
-Nonetheless, under Solaris2, the collector now (since 4.12) allocates
-memory using mmap by default.  (It defines USE_MMAP in gcconfig.h.)
-You may want to reverse this decisions if you use -DREDIRECT_MALLOC=...
-
-
-SOLARIS THREADS:
-
-The collector must be compiled with -DGC_SOLARIS_THREADS (thr_ functions)
-or -DGC_SOLARIS_PTHREADS (pthread_ functions) to be thread safe.
-It is also essential that gc.h be included in files that call thr_create,
-thr_join, thr_suspend, thr_continue, or dlopen.  Gc.h macro defines
-these to also do GC bookkeeping, etc.  Gc.h must be included with
-one or both of these macros defined, otherwise
-these replacements are not visible.
-A collector built in this way way only be used by programs that are
-linked with the threads library.
-
-In this mode, the collector contains various workarounds for older Solaris
-bugs.  Mostly, these should not be noticeable unless you look at system
-call traces.  However, it cannot protect a guard page at the end of
-a thread stack.  If you know that you will only be running Solaris2.5
-or later, it should be possible to fix this by compiling the collector
-with -DSOLARIS23_MPROTECT_BUG_FIXED.
-
-Since 5.0 alpha5, dlopen disables collection temporarily,
-unless USE_PROC_FOR_LIBRARIES is defined.  In some unlikely cases, this
-can result in unpleasant heap growth.  But it seems better than the
-race/deadlock issues we had before.
-
-If solaris_threads are used on an X86 processor with malloc redirected to
-GC_malloc, it is necessary to call GC_thr_init explicitly before forking the
-first thread.  (This avoids a deadlock arising from calling GC_thr_init
-with the allocation lock held.)
-
-It appears that there is a problem in using gc_cpp.h in conjunction with
-Solaris threads and Sun's C++ runtime.  Apparently the overloaded new operator
-is invoked by some iostream initialization code before threads are correctly
-initialized.  As a result, call to thr_self() in garbage collector
-initialization  segfaults.  Currently the only known workaround is to not
-invoke the garbage collector from a user defined global operator new, or to
-have it invoke the garbage-collector's allocators only after main has started.
-(Note that the latter requires a moderately expensive test in operator
-delete.)
-
-Hans-J. Boehm
-(The above contains my personal opinions, which are probably not shared
-by anyone else.)
diff --git a/gc/doc/README.uts b/gc/doc/README.uts
deleted file mode 100644
index 6be4966..0000000
--- a/gc/doc/README.uts
+++ /dev/null
@@ -1,2 +0,0 @@
-Alistair Crooks supplied the port.  He used Lexa C version 2.1.3 with
--Xa to compile.
diff --git a/gc/doc/README.win32 b/gc/doc/README.win32
deleted file mode 100644
index dcccec3..0000000
--- a/gc/doc/README.win32
+++ /dev/null
@@ -1,164 +0,0 @@
-The collector has at various times been compiled under Windows 95 & NT,
-with the original Microsoft SDK, with Visual C++ 2.0, 4.0, and 6, with
-the GNU win32 environment, with Borland 4.5,  with Watcom C, and recently
-with the Digital Mars compiler.  It is likely that some of these have been
-broken in the meantime.  Patches are appreciated.
-
-It runs under both win32s and win32, but with different semantics.
-Under win32, all writable pages outside of the heaps and stack are
-scanned for roots.  Thus the collector sees pointers in DLL data
-segments.  Under win32s, only the main data segment is scanned.
-(The main data segment should always be scanned.  Under some
-versions of win32s, other regions may also be scanned.)
-Thus all accessible objects should be accessible from local variables
-or variables in the main data segment.  Alternatively, other data
-segments (e.g. in DLLs) may be registered with the collector by
-calling GC_init() and then GC_register_root_section(a), where
-a is the address of some variable inside the data segment.  (Duplicate
-registrations are ignored, but not terribly quickly.)
-
-(There are two reasons for this.  We didn't want to see many 16:16
-pointers.  And the VirtualQuery call has different semantics under
-the two systems, and under different versions of win32s.)
-
-Win32 applications compiled with some flavor of gcc currently behave
-like win32s applications, in that dynamic library data segments are
-not scanned.  (Gcc does not directly support Microsoft's "structured
-exception handling".  It turns out that use of this feature is
-unavoidable if you scan arbirtray memory segments obtained from
-VirtualQuery.)
-
-The collector test program "gctest" is linked as a GUI application,
-but does not open any windows.  Its output appears in the file
-"gc.log".  It may be started from the file manager.  The hour glass
-cursor may appear as long as it's running.  If it is started from the
-command line, it will usually run in the background.  Wait a few
-minutes (a few seconds on a modern machine) before you check the output.
-You should see either a failure indication or a "Collector appears to
-work" message.
-
-The cord test program has not been ported (but should port
-easily).  A toy editor (cord/de.exe) based on cords (heavyweight
-strings represented as trees) has been ported and is included.
-It runs fine under either win32 or win32S.  It serves as an example
-of a true Windows application, except that it was written by a
-nonexpert Windows programmer.  (There are some peculiarities
-in the way files are displayed.  The <cr> is displayed explicitly
-for standard DOS text files.  As in the UNIX version, control
-characters are displayed explicitly, but in this case as red text.
-This may be suboptimal for some tastes and/or sets of default
-window colors.)
-
-In general -DREDIRECT_MALLOC is unlikely to work unless the
-application is completely statically linked.
-
-The collector normally allocates memory from the OS with VirtualAlloc.
-This appears to cause problems under Windows NT and Windows 2000 (but
-not Windows 95/98) if the memory is later passed to CreateDIBitmap.
-To work around this problem, build the collector with -DUSE_GLOBAL_ALLOC.
-This is currently incompatible with -DUSE_MUNMAP.  (Thanks to Jonathan
-Clark for tracking this down.  There's some chance this may be fixed
-in 6.1alpha4, since we now separate heap sections with an unused page.)
-
-For Microsoft development tools, rename NT_MAKEFILE as
-MAKEFILE.  (Make sure that the CPU environment variable is defined
-to be i386.)  In order to use the gc_cpp.h C++ interface, all
-client code should include gc_cpp.h.
-
-Clients may need to define GC_NOT_DLL before including gc.h, if the
-collector was built as a static library (as it normally is in the
-absence of thread support).
-
-For GNU-win32, use the regular makefile, possibly after uncommenting
-the line "include Makefile.DLLs".  The latter should be necessary only
-if you want to package the collector as a DLL.  The GNU-win32 port is
-believed to work only for b18, not b19, probably due to linker changes
-in b19.  This is probably fixable with a different definition of
-DATASTART and DATAEND in gcconfig.h.
-
-For Borland tools, use BCC_MAKEFILE.  Note that
-Borland's compiler defaults to 1 byte alignment in structures (-a1),
-whereas Visual C++ appears to default to 8 byte alignment (/Zp8).
-The garbage collector in its default configuration EXPECTS AT
-LEAST 4 BYTE ALIGNMENT.  Thus the BORLAND DEFAULT MUST
-BE OVERRIDDEN.  (In my opinion, it should usually be anyway.
-I expect that -a1 introduces major performance penalties on a
-486 or Pentium.)  Note that this changes structure layouts.  (As a last
-resort, gcconfig.h can be changed to allow 1 byte alignment.  But
-this has significant negative performance implications.)
-The Makefile is set up to assume Borland 4.5.  If you have another
-version, change the line near the top.  By default, it does not
-require the assembler.  If you do have the assembler, I recommend
-removing the -DUSE_GENERIC.
-
-There is some support for incremental collection.  This is
-currently pretty simple-minded.  Pages are protected.  Protection
-faults are caught by a handler installed at the bottom of the handler
-stack.  This is both slow and interacts poorly with a debugger.
-Whenever possible, I recommend adding a call to
-GC_enable_incremental at the last possible moment, after most
-debugging is complete.  Unlike the UNIX versions, no system
-calls are wrapped by the collector itself.  It may be necessary
-to wrap ReadFile calls that use a buffer in the heap, so that the
-call does not encounter a protection fault while it's running.
-(As usual, none of this is an issue unless GC_enable_incremental
-is called.)
-
-Note that incremental collection is disabled with -DSMALL_CONFIG.
-
-James Clark has contributed the necessary code to support win32 threads.
-Use NT_THREADS_MAKEFILE (a.k.a gc.mak) instead of NT_MAKEFILE
-to build this version.  Note that this requires some files whose names
-are more than 8 + 3 characters long.  Thus you should unpack the tar file
-so that long file names are preserved.  To build the garbage collector
-test with VC++ from the command line, use
-
-nmake /F ".\gc.mak" CFG="gctest - Win32 Release"
-
-This requires that the subdirectory gctest\Release exist.
-The test program and DLL will reside in the Release directory.
-
-This version relies on the collector residing in a dll.
-
-This version currently supports incremental collection only if it is
-enabled before any additional threads are created.
-Version 4.13 attempts to fix some of the earlier problems, but there
-may be other issues.  If you need solid support for win32 threads, you
-might check with Geodesic Systems.  Their collector must be licensed,
-but they have invested far more time in win32-specific issues.
-
-Hans
-
-Ivan V. Demakov's README for the Watcom port:
-
-The collector has been compiled with Watcom C 10.6 and 11.0.
-It runs under win32, win32s, and even under msdos with dos4gw
-dos-extender. It should also run under OS/2, though this isn't
-tested. Under win32 the collector can be built either as dll
-or as static library.
-
-Note that all compilations were done under Windows 95 or NT.
-For unknown reason compiling under Windows 3.11 for NT (one
-attempt has been made) leads to broken executables.
-
-Incremental collection is not supported.
-
-cord is not ported.
-
-Before compiling you may need to edit WCC_MAKEFILE to set target
-platform, library type (dynamic or static), calling conventions, and
-optimization options.
-
-To compile the collector and testing programs use the command:
-    wmake -f WCC_MAKEFILE
-
-All programs using gc should be compiled with 4-byte alignment.
-For further explanations on this see comments about Borland.
-
-If gc compiled as dll, the macro ``GC_DLL'' should be defined before
-including "gc.h" (for example, with -DGC_DLL compiler option). It's
-important, otherwise resulting programs will not run.
-
-Ivan Demakov (email: ivan@tgrad.nsk.su)
-
-