Build Mercury using MSVC 6.

boehm_gc/NT_MAKEFILE:
	msvc_dbg.c is in the include\private directory.

boehm_gc/msvc_dbg.c:
	Define ULONG_PTR as an int.

compiler/prog_event.m:
	ssize_t isn't defined under windows.

library/par_builtin.m:
	The CL compiler doesn't accept empty structs.

robdd/Makefile:
	-Wall isn't a valid option to CL.

runtime/mercury_mm_own_stacks.c:
runtime/mercury_term_size.c:
	Conditionally import unistd.h

runtime/mercury_trace_base.c:
	Use the correct version of snprintf.
	Fix the MR_FILE_EXISTS macro to work under win32.

boehm_gc/NT_MAKEFILE

@@ -16,7 +16,7 @@ all: gctest.exe cord\de.exe test_cpp.exe
 .cpp.obj:
 	$(cc) $(cdebug) $(cflags) $(cvars) -Iinclude -DALL_INTERIOR_POINTERS -DGC_NOT_DLL -DGC_BUILD $*.CPP /Fo$*.obj
 
-$(OBJS) tests\test.obj: include\private\gc_priv.h include\private\gc_hdrs.h include\gc.h include\private\gcconfig.h include\private\gc_locks.h include\private\gc_pmark.h include\gc_mark.h include\msvc_dbg.h
+$(OBJS) tests\test.obj: include\private\gc_priv.h include\private\gc_hdrs.h include\gc.h include\private\gcconfig.h include\private\gc_locks.h include\private\gc_pmark.h include\gc_mark.h include\private\msvc_dbg.h
 
 gc.lib: $(OBJS)
 	lib /MACHINE:i386 /out:gc.lib $(OBJS)

boehm_gc/msvc_dbg.c

@@ -34,6 +34,8 @@
 #ifdef _WIN64
 	typedef ULONG_PTR ULONG_ADDR;
 #else
+		/* the following line is needed for MSVC 6 */
+	typedef int       ULONG_PTR;
 	typedef ULONG     ULONG_ADDR;
 #endif
 

compiler/prog_event.m

@@ -203,7 +203,7 @@ read_event_set(SpecsFileName, EventSetName, EventSpecMap, ErrorSpecs, !IO) :-
                     SpecsFileName);
                 MR_make_aligned_string_copy(Problem, buf);
             } else {
-                ssize_t num_bytes_read;
+                size_t num_bytes_read;
 
                 num_bytes_read = read(spec_fd, spec_buf, stat_buf.st_size);
                 if (num_bytes_read != stat_buf.st_size) {

library/par_builtin.m

@@ -82,6 +82,7 @@
     };
 #else /* !MR_THREAD_SAFE */
     struct MR_Future {
+        char dummy; /* ANSI C doesn't allow empty structs */
     };
 #endif /* !MR_THREAD_SAFE */
 ").

robdd/Makefile

@@ -1,5 +1,5 @@
 #-----------------------------------------------------------------------------#
-# Copyright (C) 2001-2004 University of Melbourne. 
+# Copyright (C) 2001-2004,2007 University of Melbourne. 
 # This file may only be copied under the terms of the GNU General
 # Public Licence - see the file COPYING in the Mercury distribution.
 #-----------------------------------------------------------------------------#
@@ -38,7 +38,7 @@ GENFILES=$(COMMONOS) $(TESTOS)
 # Unix options
 LINKSW=-o
 DEF=-D
-MSGS=-Wall
+MSGS=
 RM=rm -f
 MV=mv
 MKDIR=mkdir

runtime/mercury_mm_own_stacks.c

@@ -19,7 +19,9 @@
 #include "mercury_dlist.h"
 
 #include <stdio.h>
-#include <unistd.h>                         /* for sleep() */
+#ifdef MR_HAVE_UNISTD_H
+  #include <unistd.h>                         /* for sleep() */
+#endif
 
 #ifdef  MR_MINIMAL_MODEL_DEBUG
   /*

runtime/mercury_term_size.c

@@ -18,7 +18,9 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <stdlib.h>
-#include <unistd.h>
+#ifdef MR_HAVE_UNISTD_H
+  #include <unistd.h>
+#endif
 #include <string.h>
 
 #ifdef MR_RECORD_TERM_SIZES

runtime/mercury_trace_base.c

@@ -43,6 +43,10 @@ ENDINIT
   #include <sys/wait.h>     /* for the wait system call */
 #endif
 
+#if defined(MR_HAVE__SNPRINTF) && ! defined(MR_HAVE_SNPRINTF)
+  #define snprintf	_snprintf
+#endif
+
 #define MR_TRACE_COUNT_SUMMARY_MAX_DEFAULT  20
 
 void                (*MR_trace_shutdown)(void) = NULL;
@@ -274,7 +278,15 @@ MR_PathPort         MR_named_count_port[MR_PORT_NONE + 1];
 #define MERCURY_TRACE_COUNTS_PREFIX     "mercury_trace_counts"
 #define TEMP_SUFFIX                     ".tmp"
 
-#define MR_FILE_EXISTS(filename)        (access(filename, F_OK) == 0)
+#if defined(F_OK)
+    /* unistd.h version */
+  #define MR_PERMISSIONS    F_OK
+#else
+    /* win32 version */
+  #define MR_PERMISSIONS    0
+#endif
+
+#define MR_FILE_EXISTS(filename)        (access(filename, MR_PERMISSIONS) == 0)
 
 void
 MR_trace_record_label_exec_counts(void *dummy)