diff --git a/lib/mac/MacMemoryAllocator/src/nsGCMalloc.c b/lib/mac/MacMemoryAllocator/src/nsGCMalloc.c
new file mode 100644
index 000000000000..e79e746860d6
--- /dev/null
+++ b/lib/mac/MacMemoryAllocator/src/nsGCMalloc.c
@@ -0,0 +1,79 @@
+/* -*- Mode: C++;    tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- 
+ * 
+ * The contents of this file are subject to the Netscape Public License 
+ * Version 1.0 (the "NPL"); you may not use this file except in 
+ * compliance with the NPL. You may obtain a copy of the NPL at  
+ * http://www.mozilla.org/NPL/ 
+ * 
+ * Software distributed under the NPL is distributed on an "AS IS" basis, 
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL 
+ * for the specific language governing rights and limitations under the 
+ * NPL. 
+ * 
+ * The Initial Developer of this code under the NPL is Netscape 
+ * Communications Corporation. Portions created by Netscape are 
+ * Copyright (C) 1998 Netscape Communications Corporation. All Rights    
+ * Reserved. */
+
+#include <string.h>
+#include <stdlib.h>
+
+#define GC_DEBUG
+#include "gc.h"
+
+// GC implementation of malloc/free, for testing purposes
+
+//--------------------------------------------------------------------
+void *malloc(size_t blockSize)
+//--------------------------------------------------------------------
+{
+	return GC_MALLOC(blockSize);
+}
+
+
+//--------------------------------------------------------------------
+void free(void *deadBlock)
+//--------------------------------------------------------------------
+{
+	if (deadBlock != NULL)
+		GC_FREE(deadBlock);
+}
+
+
+//--------------------------------------------------------------------
+void* realloc(void* block, size_t newSize)
+//--------------------------------------------------------------------
+{
+#ifdef GC_DEBUG
+	return GC_REALLOC(block, newSize);
+#else
+    size_t oldSize = GC_size(block);
+    void * newBlock = block;
+ 
+    if (newSize <= 10000)
+    	return(GC_REALLOC(block, newSize));
+    
+    if (newSize <= oldSize)
+    	return(block);
+    	
+    newBlock = GC_malloc_ignore_off_page(newSize);
+    if (newBlock == NULL)
+    	return NULL;
+    
+    memcpy(newBlock, block, oldSize);
+    GC_FREE(block);
+    
+    return(newBlock);
+#endif
+}
+
+//--------------------------------------------------------------------
+void *calloc(size_t nele, size_t elesize)
+//--------------------------------------------------------------------
+{
+	size_t	space = nele * elesize;
+	void	*newBlock = malloc(space);
+	if (newBlock)
+		memset(newBlock, 0, space);
+	return newBlock;
+}