Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753212AbYKXO23 (ORCPT ); Mon, 24 Nov 2008 09:28:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752621AbYKXO2U (ORCPT ); Mon, 24 Nov 2008 09:28:20 -0500 Received: from gv-out-0910.google.com ([216.239.58.191]:14149 "EHLO gv-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750983AbYKXO2T (ORCPT ); Mon, 24 Nov 2008 09:28:19 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :content-type:content-transfer-encoding; b=AoJIWwlIM93FmWtCQ3SQNVdkHU53fA+kHyQ9NkXfRCdeY3Hm0WJXRJhh8KxgSqI17o QfGh2iUxpSjJtdBkE34CYdCKXPCu7lLnZvzrvVO0HeGqh9y9+/rafog34xwxsQnNek2B nLV0Wbsy8coW4qjjVcaAZazCe8r12AAy6FroQ= Message-ID: <492AB9FD.5010602@gmail.com> Date: Mon, 24 Nov 2008 16:28:13 +0200 From: =?ISO-8859-1?Q?T=F6r=F6k_Edwin?= User-Agent: Mozilla-Thunderbird 2.0.0.17 (X11/20081018) MIME-Version: 1.0 To: James.Bottomley@HansenPartnership.com CC: linux-scsi@vger.kernel.org, Linux Kernel Subject: 2.6.28-rc6-tip fails to build with gcc 4.4.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1253 Lines: 42 Hi, Using gcc version 4.4.0 20081120 (experimental) [trunk revision 142055] I can't build latest tip/master (commit b27fef5b222564b6e7ae71f7110c233b2fb45a38) drivers/built-in.o: In function `sd_revalidate_disk': sd.c:(.text+0x8bc76): undefined reference to `____ilog2_NaN' make: *** [.tmp_vmlinux1] Error 1 Apparently gcc determines that sector_size can have an invalid constant value as ilog2's parameter in sd_read_capacity. I tried to narrow down, but all I found so far is that gcc 4.4.0 now says that __builtin_constant_p() is true even in these cases: a = .. constant value ... if (cond) { a = ... constant value ... } __builtin_constant_p(a) ? .... a = .. constant value ... if (cond) { a = ... constant value ... } else { a = ... another constant value ... } __builtin_constant_p(a) ? .... I guess it clones the __builtin_constant_p for each branch, where a is constant, gcc 4.3 doesn't seem to do that. Did it find a real bug in sd.c, or is it a gcc bug? Best regards, --Edwin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/