From ac43da8466971553001e7105e03d514b72721814 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 18 Jul 2005 15:53:28 +0000
Subject: [PATCH] MemSet() must not cast its pointer argument to int32* until
after it has checked that the pointer is actually word-aligned. Casting a
non-aligned pointer to int32* is technically illegal per the C spec, and some
recent versions of gcc actually generate bad code for the memset() when given
such a pointer. Per report from Andrew Morrow.
---
src/include/c.h | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/src/include/c.h b/src/include/c.h
index 4567e2102d5..7752e1ae02d 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -12,7 +12,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/c.h,v 1.187 2005/07/02 17:01:52 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/c.h,v 1.188 2005/07/18 15:53:28 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -630,21 +630,22 @@ typedef NameData *Name;
#define MemSet(start, val, len) \
do \
{ \
- int32 *_start = (int32 *) (start); \
+ void *_vstart = (void *) (start); \
int _val = (val); \
Size _len = (len); \
\
- if ((((long) _start) & INT_ALIGN_MASK) == 0 && \
+ if ((((long) _vstart) & INT_ALIGN_MASK) == 0 && \
(_len & INT_ALIGN_MASK) == 0 && \
_val == 0 && \
_len <= MEMSET_LOOP_LIMIT) \
{ \
+ int32 *_start = (int32 *) _vstart; \
int32 *_stop = (int32 *) ((char *) _start + _len); \
while (_start < _stop) \
*_start++ = 0; \
} \
else \
- memset(_start, _val, _len); \
+ memset(_vstart, _val, _len); \
} while (0)
#define MEMSET_LOOP_LIMIT 1024
--
GitLab