Date: Sat, 29 Aug 2009 11:24:14 GMT From: Rafaël Carré <rafael.carre@gmail.com> To: freebsd-gnats-submit@FreeBSD.org Subject: standards/138307: posix_memalign has incorrect behaviour if size == 0 Message-ID: <200908291124.n7TBOEKl097272@www.freebsd.org> Resent-Message-ID: <200908291130.n7TBU2Dk060280@freefall.freebsd.org>
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>Number: 138307 >Category: standards >Synopsis: posix_memalign has incorrect behaviour if size == 0 >Confidential: no >Severity: non-critical >Priority: low >Responsible: freebsd-standards >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Sat Aug 29 11:30:02 UTC 2009 >Closed-Date: >Last-Modified: >Originator: Rafaël Carré >Release: 8-BETA2 >Organization: >Environment: FreeBSD kru 8.0-BETA2 FreeBSD 8.0-BETA2 #1: Thu Aug 13 15:49:26 CEST 2009 fun@kru:/usr/obj/usr/src/sys/GENERIC amd64 >Description: http://www.opengroup.org/onlinepubs/9699919799/functions/posix_memalign.html quotes: "If the size of the space requested is 0, the behavior is implementation-defined; the value returned in memptr shall be either a null pointer or a unique pointer." The behaviour is different using differents alignements: posix_memalign either returns EINVAL, either asserts. Sample test program is attached, output is: --8<-- % ./a.out malloc 0 align 4 Invalid argument align 8 Assertion failed: (size != 0), function arena_malloc, file /usr/src/lib/libc/stdlib/malloc.c, line 3349. zsh: abort (core dumped) ./a.out --8<-- call stack: #2 0x000000080071c225 in __assert () from /lib/libc.so.7 #3 0x00000008006be011 in malloc_usable_size () from /lib/libc.so.7 #4 0x00000008006c1228 in posix_memalign () from /lib/libc.so.7 I got a report that it functions correctly on "FreeBSD turbine 7.1-RELEASE-p5 FreeBSD 7.1-RELEASE-p5 #7 r191765: Thu Aug 20 12:26:09 CEST 2009" but I can't test myself >How-To-Repeat: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> int main(void) { void *p; int i; errno = 0; printf("malloc 0\n"); p = malloc(0); if(!p) printf("%s\n", strerror(errno)); printf("\n"); printf("align 4\n"); i = posix_memalign(&p, 4, 0); printf("%s\n\n", strerror(i)); printf("align 8\n"); i = posix_memalign(&p, 8, 0); printf("%s\n\n", strerror(i)); return 0; } >Fix: >Release-Note: >Audit-Trail: >Unformatted:
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