* lisp.h (SAFE_ALLOCA, SAFE_ALLOCA_LISP): Avoid 'int' overflow

leading to a memory leak, possible in functions like
load_charset_map_from_file that can allocate an unbounded number
of objects.

2 files changed, 7 insertions, 2 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index c8fa1e55695..a341d1b4678 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,10 @@
 2011-03-22  Paul Eggert  <eggert@cs.ucla.edu>
 
+        * lisp.h (SAFE_ALLOCA, SAFE_ALLOCA_LISP): Avoid 'int' overflow
+        leading to a memory leak, possible in functions like
+        load_charset_map_from_file that can allocate an unbounded number
+        of objects.
+
         * xmenu.c (set_frame_menubar): Use EMACS_UINT, not int, for indexes
         that could (at least in theory) be that large.
 
diff --git a/src/lisp.h b/src/lisp.h
index 645b82c80cf..e98172ec104 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3602,7 +3602,7 @@ extern Lisp_Object safe_alloca_unwind (Lisp_Object);
     else                                                  \
       {                                                   \
         buf = (type) xmalloc (size);                      \
-        sa_must_free++;                                   \
+        sa_must_free = 1;                                 \
         record_unwind_protect (safe_alloca_unwind,        \
                                make_save_value (buf, 0)); \
       }                                                   \
@@ -3632,7 +3632,7 @@ extern Lisp_Object safe_alloca_unwind (Lisp_Object);
         buf = (Lisp_Object *) xmalloc (size_);            \
         arg_ = make_save_value (buf, nelt);               \
         XSAVE_VALUE (arg_)->dogc = 1;                     \
-        sa_must_free++;                                   \
+        sa_must_free = 1;                                 \
         record_unwind_protect (safe_alloca_unwind, arg_); \
       }                                                   \
   } while (0)