From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 100515 invoked by alias); 27 Apr 2018 18:47:04 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 100492 invoked by uid 89); 27 Apr 2018 18:47:02 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-7.6 required=5.0 tests=AWL,BAYES_00,GIT_PATCH_3,KAM_SHORT,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=drag, punt X-HELO: mx1.redhat.com Received: from mx3-rdu2.redhat.com (HELO mx1.redhat.com) (66.187.233.73) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 27 Apr 2018 18:47:01 +0000 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 24A0210D420; Fri, 27 Apr 2018 18:47:00 +0000 (UTC) Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id A4E2BAB3FE; Fri, 27 Apr 2018 18:46:59 +0000 (UTC) Subject: Re: [RFA v2 2/6] Handle alignof and _Alignof To: Tom Tromey , gdb-patches@sourceware.org References: <20180427140139.7957-1-tom@tromey.com> <20180427140139.7957-3-tom@tromey.com> From: Pedro Alves Message-ID: <2acfa770-0ec2-b675-a139-f350aa059da0@redhat.com> Date: Fri, 27 Apr 2018 18:47:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180427140139.7957-3-tom@tromey.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2018-04/txt/msg00575.txt.bz2 On 04/27/2018 03:01 PM, Tom Tromey wrote: > This adds alignof and _Alignof to the C/C++ expression parser, and > adds new tests to test the features. The tests are written to try to > ensure that gdb's knowledge of alignment rules stays in sync with the > compiler's. This looks good to me. A few comments on additional tests below, but there's no need for another round of review for those. > +++ b/gdb/testsuite/gdb.cp/align.exp > @@ -0,0 +1,145 @@ ... > + > +# Prologue. > +puts $outfile { > + template > + struct align_pair > + { > + T one; > + U two; > + }; > + > + template > + struct align_union > + { > + T one; > + U two; > + }; > + > + enum bigenum { VALUE = 0xffffffffull }; > + > + struct empty { }; > + > + struct vstruct { virtual ~vstruct() {} char c; }; > + > + struct bfstruct { unsigned b : 3; }; > + > + struct arrstruct { short fld[7]; }; Sorry to be a drag, but I think it'd be good to add a few more tests here: - alignof(typedef) (to make sure we're not missing a check_typedef call somewhere. e.g., add "typedef arrstruct arrstruct_t", then add arrstruct_t to the list of tested types. - alignof(a class with a base class). E.g.,: struct A { int i;}; struct B : A { char c; }; and then check alignof(B). multiple and virtual inheritance might be worth testing too, not sure whether the code paths are (and will always be) the same. - alignof(array-type) This is what I actually meant by arrays in v1. E.g.: alignof (int[3]) It might be we don't parse that. Not sure. If it's hard, it's ok to punt, but then it'd be good to still add the test and kfail it. > +proc maybe_xfail {type} { > + # See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69560 > + # The g++ implementation of alignof is changing to match C11. > + if {[is_x86_like_target] > + && ($type == "double" || $type == "long long" > + || $type == "unsigned long long")} { > + setup_xfail *-*-* It seems like we can check for gcc version with test_compiler_info. Maybe go ahead and limit the xfail to: [test_compiler_info {gcc-[0-8]-*}] ? Thanks, Pedro Alves