X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/7c420169baa7c50428589cca7f8eda71b462eb15..b2e4ca7d12b306cd15d4ec24ce7749db56729e2b:/src/w32heap.c

diff --git a/src/w32heap.c b/src/w32heap.c
index 39ff101746..35ac4cbf31 100644
--- a/src/w32heap.c
+++ b/src/w32heap.c
@@ -1,6 +1,5 @@
 /* Heap management routines for GNU Emacs on the Microsoft W32 API.
-   Copyright (C) 1994, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
-                 2008, 2009, 2010  Free Software Foundation, Inc.
+   Copyright (C) 1994, 2001-2012  Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
@@ -115,6 +114,7 @@ get_data_end (void)
   return data_region_end;
 }
 
+#if !defined (USE_LISP_UNION_TYPE) && !defined (USE_LSB_TAG)
 static char *
 allocate_heap (void)
 {
@@ -141,9 +141,31 @@ allocate_heap (void)
 
   return ptr;
 }
+#else  /* USE_LISP_UNION_TYPE || USE_LSB_TAG */
+static char *
+allocate_heap (void)
+{
+  unsigned long size = 0x80000000; /* start by asking for 2GB */
+  void *ptr = NULL;
+
+  while (!ptr && size > 0x00100000)
+    {
+      reserved_heap_size = size;
+      ptr = VirtualAlloc (NULL,
+			  get_reserved_heap_size (),
+			  MEM_RESERVE,
+			  PAGE_NOACCESS);
+      size -= 0x00800000; /* if failed, decrease request by 8MB */
+    }
+
+  return ptr;
+}
+#endif /* USE_LISP_UNION_TYPE || USE_LSB_TAG */
 
 
-/* Emulate Unix sbrk.  */
+/* Emulate Unix sbrk.  Note that ralloc.c expects the return value to
+   be the address of the _start_ (not end) of the new block in case of
+   success, and zero (not -1) in case of failure.  */
 void *
 sbrk (unsigned long increment)
 {