* makefile.w32-in: Update dependencies.

[gnu-emacs] / src / ralloc.c

diff --git a/src/ralloc.c b/src/ralloc.c
index 61f7aff95f54039a895abd0282ec84a1a58bff5c..f5ebb8449ca57374d50f399803f9475807c96792 100644 (file)
--- a/src/ralloc.c
+++ b/src/ralloc.c
@@ -1,6 +1,6 @@
 /* Block-relocating memory allocator.
    Copyright (C) 1993, 1995, 2000, 2001, 2002, 2003, 2004,
-                 2005, 2006, 2007, 2008  Free Software Foundation, Inc.
+                 2005, 2006, 2007, 2008, 2009  Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
@@ -402,6 +402,11 @@ find_bloc (ptr)
 
   while (p != NIL_BLOC)
     {
+      /* Consistency check. Don't return inconsistent blocs.
+        Don't abort here, as callers might be expecting this,  but
+        callers that always expect a bloc to be returned should abort
+        if one isn't to avoid a memory corruption bug that is
+        difficult to track down.  */
       if (p->variable == ptr && p->data == *ptr)
        return p;
 
@@ -981,7 +986,7 @@ r_alloc_free (ptr)
 
   dead_bloc = find_bloc (ptr);
   if (dead_bloc == NIL_BLOC)
-    abort ();
+    abort (); /* Double free? PTR not originally used to allocate?  */
 
   free_bloc (dead_bloc);
   *ptr = 0;
@@ -1025,7 +1030,7 @@ r_re_alloc (ptr, size)
 
   bloc = find_bloc (ptr);
   if (bloc == NIL_BLOC)
-    abort ();
+    abort (); /* Already freed? PTR not originally used to allocate?  */
 
   if (size < bloc->size)
     {
@@ -1246,7 +1251,7 @@ r_alloc_reset_variable (old, new)
     }
 
   if (bloc == NIL_BLOC || bloc->variable != old)
-    abort ();
+    abort (); /* Already freed? OLD not originally used to allocate?  */
 
   /* Update variable to point to the new location.  */
   bloc->variable = new;