* alloc.c (allocate_buffer): Don't assume sizeof (struct buffer) is a

multiple of sizeof (EMACS_INT); it need not be, if
alignof(EMACS_INT) < sizeof (EMACS_INT).

2 files changed, 5 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index fa2aa03233d..81053d74480 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -6,6 +6,9 @@
         don't formally overflow signed char, to avoid warnings.
         (allocate_string_data) [GC_CHECK_STRING_OVERRUN]: Fix typo that
         can cause Emacs to crash when string overrun checking is enabled.
+        (allocate_buffer): Don't assume sizeof (struct buffer) is a
+        multiple of sizeof (EMACS_INT); it need not be, if
+        alignof(EMACS_INT) < sizeof (EMACS_INT).
 
 2011-04-17  Chong Yidong  <cyd@stupidchicken.com>
 
diff --git a/src/alloc.c b/src/alloc.c
index 2af75e3c471..2d1c8ffe70b 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -1055,7 +1055,8 @@ allocate_buffer (void)
   struct buffer *b
     = (struct buffer *) lisp_malloc (sizeof (struct buffer),
                                      MEM_TYPE_BUFFER);
-  b->size = sizeof (struct buffer) / sizeof (EMACS_INT);
+  b->size = ((sizeof (struct buffer) + sizeof (EMACS_INT) - 1)
+             / sizeof (EMACS_INT));
   XSETPVECTYPE (b, PVEC_BUFFER);
   return b;
 }