implement GC_remove_roots for win32 by letting it use the nonwin32 codepath. feels kinda scary. see this question on boehm maillinglist:

http://permalink.gmane.org/gmane.comp.programming.garbage-collection.boehmgc/4732

Author: lucasmeijer

libgc/include/gc.h

@@ -959,6 +959,8 @@ extern void GC_thr_init(void);	/* Needed for Solaris/X86	*/
 
 #endif /* defined(GC_WIN32_THREADS)  && !cygwin */
 
+#define UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS 1
+
  /*
   * Fully portable code should call GC_INIT() from the main program
   * before making any other GC_ calls.  On most platforms this is a

libgc/include/private/gc_priv.h

@@ -797,14 +797,14 @@ struct exclusion {
 struct roots {
 	ptr_t r_start;
 	ptr_t r_end;
-#	if !defined(MSWIN32) && !defined(MSWINCE)
+#	if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
 	  struct roots * r_next;
 #	endif
 	GC_bool r_tmp;
 	  	/* Delete before registering new dynamic libraries */
 };
 
-#if !defined(MSWIN32) && !defined(MSWINCE)
+#if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
     /* Size of hash table index to roots.	*/
 #   define LOG_RT_SIZE 6
 #   define RT_SIZE (1 << LOG_RT_SIZE) /* Power of 2, may be != MAX_ROOT_SETS */
@@ -997,7 +997,7 @@ struct _GC_arrays {
     		/* Commited lengths of memory regions obtained from kernel. */
 # endif
   struct roots _static_roots[MAX_ROOT_SETS];
-# if !defined(MSWIN32) && !defined(MSWINCE)
+# if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
     struct roots * _root_index[RT_SIZE];
 # endif
   struct exclusion _excl_table[MAX_EXCLUSIONS];

libgc/mark_rts.c

@@ -32,6 +32,7 @@ struct roots {
 struct roots GC_static_roots[MAX_ROOT_SETS];
 */
 
+
 int GC_no_dls = 0;	/* Register dynamic library data segments.	*/
 
 static int n_root_sets = 0;
@@ -87,7 +88,7 @@ ptr_t p;
     return(FALSE);
 }
 
-#if !defined(MSWIN32) && !defined(MSWINCE)
+#if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
 /* 
 #   define LOG_RT_SIZE 6
 #   define RT_SIZE (1 << LOG_RT_SIZE)  -- Power of 2, may be != MAX_ROOT_SETS
@@ -175,7 +176,7 @@ GC_bool tmp;
 {
     struct roots * old;
 
-#   if defined(MSWIN32) || defined(MSWINCE)
+#   if defined(MSWIN32) || defined(MSWINCE) && !UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
       /* Spend the time to ensure that there are no overlapping	*/
       /* or adjacent intervals.					*/
       /* This could be done faster with e.g. a			*/
@@ -222,7 +223,7 @@ GC_bool tmp;
                   GC_root_size -= (other -> r_end - other -> r_start);
                   other -> r_start = GC_static_roots[n_root_sets-1].r_start;
                   other -> r_end = GC_static_roots[n_root_sets-1].r_end;
-                                  n_root_sets--;
+                  n_root_sets--;
               }
             }
           return;
@@ -285,7 +286,7 @@ int i;
     n_root_sets--;
 }
 
-#if !defined(MSWIN32) && !defined(MSWINCE)
+#if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
 static void GC_rebuild_root_index()
 {
     register int i;
@@ -313,7 +314,7 @@ void GC_remove_tmp_roots()
     #endif
 }
 
-#if !defined(MSWIN32) && !defined(MSWINCE)
+#if !defined(MSWIN32) && !defined(MSWINCE) || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
 void GC_remove_roots(b, e)
 char * b; char * e;
 {

mono/metadata/boehm-gc.c

@@ -318,7 +318,7 @@ mono_gc_register_root (char *start, size_t size, void *descr)
 void
 mono_gc_deregister_root (char* addr)
 {
-#ifndef PLATFORM_WIN32
+#ifndef PLATFORM_WIN32 || UNITY_USE_REASONABLE_LOOKING_GCROOTS_CODEPATH_ON_WINDOWS
 	/* FIXME: libgc doesn't define this work win32 for some reason */
 	/* FIXME: No size info */
 	GC_remove_roots (addr, addr + sizeof (gpointer) + 1);