From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759225AbaGDQ50 (ORCPT ); Fri, 4 Jul 2014 12:57:26 -0400 Received: from smtprelay0205.hostedemail.com ([216.40.44.205]:53877 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752622AbaGDQ5Z (ORCPT ); Fri, 4 Jul 2014 12:57:25 -0400 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::::::::::::::::,RULES_HIT:41:355:379:541:599:800:960:973:988:989:1260:1261:1277:1311:1313:1314:1345:1359:1373:1437:1515:1516:1518:1534:1543:1593:1594:1711:1730:1747:1777:1792:2393:2553:2559:2562:2828:3138:3139:3140:3141:3142:3355:3622:3865:3867:3868:3870:3871:3872:3874:4250:4321:5007:6117:6119:6235:7557:7558:7652:7903:10004:10400:10848:10967:11026:11232:11473:11658:11914:12043:12438:12517:12519:12740:13972:14093:14097:21060:21080,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF: X-HE-Tag: quill56_61e4df56bc58 X-Filterd-Recvd-Size: 4297 Message-ID: <1404493040.6384.21.camel@joe-AO725> Subject: Re: [PATCH 3/4] DRBG: Fix format string for debugging statements From: Joe Perches To: Dan Carpenter Cc: Stephan Mueller , Stephen Rothwell , Herbert Xu , kbuild test robot , kbuild@01.org, linux-crypto@vger.kernel.org, Randy Dunlap , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Date: Fri, 04 Jul 2014 09:57:20 -0700 In-Reply-To: <20140704112116.GC25934@mwanda> References: <4927386.WYHrRe3NJm@myon.chronox.de> <10901956.0EDQunEZJL@myon.chronox.de> <20140629122402.0fd014d8@canb.auug.org.au> <4311965.FMe9YfRAnU@myon.chronox.de> <1404013999.9064.50.camel@joe-AO725> <20140704112116.GC25934@mwanda> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.10.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2014-07-04 at 14:21 +0300, Dan Carpenter wrote: > On Sat, Jun 28, 2014 at 08:53:19PM -0700, Joe Perches wrote: > > On Sun, 2014-06-29 at 05:46 +0200, Stephan Mueller wrote: > > > Am Sonntag, 29. Juni 2014, 12:24:02 schrieb Stephen Rothwell: > > > > > > Hi Stephen, > > > > > > > Hi Stephan, > > > > > > > > On Sat, 28 Jun 2014 22:01:46 +0200 Stephan Mueller > > > wrote: > > > > > @@ -1987,8 +1987,9 @@ static int __init drbg_init(void) > > > > > > > > > > if (ARRAY_SIZE(drbg_cores) * 2 > ARRAY_SIZE(drbg_algs)) { > > > > > > > > > > pr_info("DRBG: Cannot register all DRBG types" > > > > > > > > > > - "(slots needed: %lu, slots available: %lu)\n", > > > > > - ARRAY_SIZE(drbg_cores) * 2, ARRAY_SIZE(drbg_algs)); > > > > > + "(slots needed: %u, slots available: %u)\n", > > > > > + (unsigned int)ARRAY_SIZE(drbg_cores) * 2, > > > > > + (unsigned int)ARRAY_SIZE(drbg_algs)); > > > > > > > > Doesn't ARRAY_SIZE() always return a size_t? In which case surely we > > > > need no casts, but need to us %zu in the format string. > > > > > > Unfortunately not at all. On my x86_64, I get the compiler warning that > > > ARRAY_SIZE is a long unsigned int without the cast. It doesn't seem to for 4.8. Is there some specific gcc version where this occurs? > > diff --git a/include/linux/kernel.h b/include/linux/kernel.h [] > > -#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) > > +#define ARRAY_SIZE(arr) \ > > + (sizeof(arr) / sizeof((arr)[0]) + (size_t)__must_be_array(arr)) > > > This change is a no-op isn't it? Yes, it is. Dumb idea. Assuming there's some odd promotion, size_t should have been around the whole thing #define ARRAY_SIZE(arr) \ ((size_t)((sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))) > I think Stephen Rothwell's suggestion > is correct. In linux-next this was changed to %lu which also works... > > Are there arches %zu and %lu are different? I get the same output types and error warnings compiling this either -m32 or -m64 #include #include #define typecheck(type, x) \ ({ \ type __dummy; \ typeof(x) __dummy2; \ (void)(&__dummy == &__dummy2); \ 1; \ }) #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) int main(int argc, char **argv) { char foo[100]; size_t array = sizeof(foo); typeof (ARRAY_SIZE(foo)) member = ARRAY_SIZE(foo); int member1 = ARRAY_SIZE(foo); size_t member2 = ARRAY_SIZE(foo); typecheck(size_t, member); typecheck(int, member); typecheck(size_t, member1); typecheck(int, member1); typecheck(size_t, member2); typecheck(int, member2); printf("array: %zu, member: %zu\n", array, (int)member); return 0; }