From 183b1bf84f127f420451f9eb0bc74c86af238cfa Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 18 Jul 2005 15:53:46 +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 | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/src/include/c.h b/src/include/c.h index 5f884d8f2f0..08ce6dd243f 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 1.178 2004/12/31 22:03:18 pgsql Exp $ + * $PostgreSQL: pgsql/src/include/c.h,v 1.178.4.1 2005/07/18 15:53:46 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -593,21 +593,22 @@ 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 * _stop = (int32 *) ((char *) _start + _len); \ + int32 *_start = (int32 *) _vstart; \ + int32 *_stop = (int32 *) ((char *) _start + _len); \ while (_start < _stop) \ *_start++ = 0; \ } \ else \ - memset((char *) _start, _val, _len); \ + memset(_vstart, _val, _len); \ } while (0) #define MEMSET_LOOP_LIMIT 1024 -- 2.39.5