From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12133 invoked by alias); 20 Aug 2012 23:21:48 -0000 Received: (qmail 12124 invoked by uid 22791); 20 Aug 2012 23:21:47 -0000 X-SWARE-Spam-Status: No, hits=-4.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00,KHOP_THREADED 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; Mon, 20 Aug 2012 23:21:33 +0000 From: "luto at mit dot edu" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/54336] [c++0x] diagnostics for functions with arg-dependent return types have bad signatures Date: Mon, 20 Aug 2012 23:21:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c++ X-Bugzilla-Keywords: X-Bugzilla-Severity: minor X-Bugzilla-Who: luto at mit dot edu X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- 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: 2012-08/txt/msg01415.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54336 --- Comment #2 from Andy Lutomirski 2012-08-20 23:21:32 UTC --- Fair enough. Here's a better example: struct A { int method(); }; template auto func(T x) -> decltype(x.method()) { bogus(x); } int main() { func(A()); } The error is: decltype_return.cc: In instantiation of 'decltype (x.method()) func(T) [with T = A; decltype (x.method()) = int]': decltype_return.cc:8:22: required from here decltype_return.cc:5:3: error: 'bogus' was not declared in this scope bogus(x); ^ 'decltype (x.method())' is still meaningless in that context. Even just 'auto func(T) [with ...; auto = int]' might be less puzzling. (This is a very minor issue -- I just found it puzzling when I hit it earlier today in an STL error message.)