diff -bcrN gc.org/doc/README.ews4800 gc/doc/README.ews4800
*** gc.org/doc/README.ews4800	Thu Jan  1 09:00:00 1970
--- gc/doc/README.ews4800	Wed Jul 25 17:38:57 2001
***************
*** 0 ****
--- 1,75 ----
+ 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>
+ 
diff -bcrN gc.org/include/private/gcconfig.h gc/include/private/gcconfig.h
*** gc.org/include/private/gcconfig.h	Sun Jul  1 06:29:27 2001
--- gc/include/private/gcconfig.h	Wed Jul 25 17:38:57 2001
***************
*** 75,83 ****
  #    endif
  #    define mach_type_known
  # endif
! # if defined(mips) || defined(__mips)
  #    define MIPS
! #    if !defined(LINUX)
  #      if defined(ultrix) || defined(__ultrix) || defined(__NetBSD__)
  #	 define ULTRIX
  #      else
--- 75,86 ----
  #    endif
  #    define mach_type_known
  # endif
! # if defined(mips) || defined(__mips) || defined(_mips)
  #    define MIPS
! #    if defined(nec_ews) || defined(_nec_ews)
! #      define EWS4800
! #    endif
! #    if !defined(LINUX) && !defined(EWS4800)
  #      if defined(ultrix) || defined(__ultrix) || defined(__NetBSD__)
  #	 define ULTRIX
  #      else
***************
*** 1083,1088 ****
--- 1086,1114 ----
  	/* instead. But some kernel versions seem to give the wrong	*/
  	/* value from /proc.						*/
  #   endif /* Linux */
+ #   ifdef EWS4800
+ #      define HEURISTIC2
+ #      if defined(_MIPS_SZPTR) && (_MIPS_SZPTR == 64)
+          extern int _fdata[], _end[];
+ #        define DATASTART ((ptr_t)_fdata)
+ #        define DATAEND ((ptr_t)_end)
+ #        define CPP_WORDSZ _MIPS_SZPTR
+ #        define ALIGNMENT (_MIPS_SZPTR/8)
+ #      else
+          extern int etext, edata, end;
+          extern int _DYNAMIC_LINKING, _gp;
+ #        define DATASTART ((ptr_t)((((word)&etext + 0x3ffff) & ~0x3ffff) \
+                + ((word)&etext & 0xffff)))
+ #        define DATAEND (&edata)
+ #        define DATASTART2 (&_DYNAMIC_LINKING \
+                ? (ptr_t)(((word)&_gp + 0x8000 + 0x3ffff) & ~0x3ffff) \
+                : (ptr_t)&edata)
+ #        define DATAEND2 (&end)
+ #        define ALIGNMENT 4
+ #      endif
+ #      define OS_TYPE "EWS4800"
+ #      define USE_GENERIC_PUSH_REGS 1
+ #   endif
  #   ifdef ULTRIX
  #	define HEURISTIC2
  #       define DATASTART (ptr_t)0x10000000
diff -bcrN gc.org/mach_dep.c gc/mach_dep.c
*** gc.org/mach_dep.c	Thu Jun 28 05:54:23 2001
--- gc/mach_dep.c	Wed Jul 25 17:38:57 2001
***************
*** 429,435 ****
  		    *i = 0;
  		}
  #	      if defined(POWERPC) || defined(MSWIN32) || defined(MSWINCE) \
! 	         || defined(UTS4) || defined(LINUX)
  		  (void) setjmp(regs);
  #	      else
  	          (void) _setjmp(regs);
--- 429,435 ----
  		    *i = 0;
  		}
  #	      if defined(POWERPC) || defined(MSWIN32) || defined(MSWINCE) \
!                 || defined(UTS4) || defined(LINUX) || defined(EWS4800)
  		  (void) setjmp(regs);
  #	      else
  	          (void) _setjmp(regs);
diff -bcrN gc.org/os_dep.c gc/os_dep.c
*** gc.org/os_dep.c	Tue Jun 26 11:32:26 2001
--- gc/os_dep.c	Wed Jul 25 17:38:57 2001
***************
*** 1088,1093 ****
--- 1088,1096 ----
  	GC_add_roots_inner(DATASTART, (char *)sbrk(0), FALSE);
  #     else
  	GC_add_roots_inner(DATASTART, (char *)(DATAEND), FALSE);
+ #       if defined(DATASTART2)
+          GC_add_roots_inner(DATASTART2, (char *)(DATAEND2), FALSE);
+ #       endif
  #     endif
  #   endif
  #   if !defined(PCR) && (defined(NEXT) || defined(MACOSX))