From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28289 invoked by alias); 26 Apr 2015 18:00:52 -0000 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 Received: (qmail 28269 invoked by uid 48); 26 Apr 2015 18:00:48 -0000 From: "msebor at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/65892] gcc fails to implement N685 aliasing of union members Date: Sun, 26 Apr 2015 18:00:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 5.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: msebor at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2015-04/txt/msg02229.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65892 --- Comment #6 from Martin Sebor --- I agree it's subtle and could be clearer but I believe the key phrase is "a union contains several structures." Here, the term "union" refers to the type, not the object. This is supported by the use of the term "union object" in the second part of the sentence. This interpretation is in line with Derek Jones' excellent The New C Standard -- An Economic and Cultural Commentary: http://www.coding-guidelines.com/cbook But if there's doubt that this interpretation is intended I'd be happy to raise an interpretation request on the WG14 mailing list.