From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24031 invoked by alias); 1 Dec 2011 10:26:31 -0000 Received: (qmail 24021 invoked by uid 22791); 1 Dec 2011 10:26:30 -0000 X-SWARE-Spam-Status: No, hits=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 01 Dec 2011 10:26:16 +0000 From: "iains at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/50325] [4.7 Regression] 76 new fails with rev. 177691 Date: Thu, 01 Dec 2011 10:26:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Keywords: X-Bugzilla-Severity: critical X-Bugzilla-Who: iains at gcc dot gnu.org X-Bugzilla-Status: REOPENED X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.7.0 X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2011-12/txt/msg00036.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50325 --- Comment #24 from Iain Sandoe 2011-12-01 10:25:33 UTC --- well.. sorry, that might be a bogus comment - it depends on whether the following can be interpreted to allow a different layout on the stack from 'normal' memory. Since the embedding alignment of bitfields doesn't seem to be specifically referenced in the struct. layout section (pp10 in the pdf) - other than saying that it's 'natural' if the first element and 4 bytes otherwise. but page14 in the pdf of the ABI doc has: 1. All nonvector parameters are aligned on 4-byte boundaries. 2. Vector parameters are aligned on 16-byte boundaries. 3. Noncomposite parameters (that is, parameters that are not arrays or data structures) smaller than 4 bytes occupy the high-order bytes of their 4-byte area. 4. Composite parameters (arrays, structures, and unions) 1 or 2 bytes in size occupy the low-order bytes of their 4-byte area. They are preceded by padding to 4 bytes. This rule is inconsistent with other 32-bit PowerPC binary inter faces. In AIX and Mac OS 9 (and earlier), padding bytes always follow the data structure even in the case of composite parameters smaller than 4 bytes. 5. Composite parameters 3 bytes or larger in size occupy the high-order bytes of their 4-byte area. They are followed by padding to make a multiple of 4 bytes, with the padding bytes being undefined. again no specific mention of bitfields ...