From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 125857 invoked by alias); 29 Jun 2017 17:02:20 -0000 Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org Received: (qmail 125640 invoked by uid 89); 29 Jun 2017 17:02:20 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy= X-Spam-User: qpsmtpd, 2 recipients X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 29 Jun 2017 17:02:19 +0000 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CC71367AC8; Thu, 29 Jun 2017 17:02:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com CC71367AC8 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=palves@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com CC71367AC8 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 13B3060F90; Thu, 29 Jun 2017 17:02:04 +0000 (UTC) Subject: Re: [RFC PATCH 0/3] Pretty-printing for errno To: Phil Muldoon , Zack Weinberg , libc-alpha@sourceware.org, gdb@sourceware.org References: <20170622224456.1358-1-zackw@panix.com> <3a7946e9-d178-f878-9774-64ff44bcf5df@redhat.com> Cc: joseph@codesourcery.com, fweimer@redhat.com, tom@tromey.com, siddhesh@gotplt.org From: Pedro Alves Message-ID: <9490d183-a57b-b336-3131-6580e4773818@redhat.com> Date: Thu, 29 Jun 2017 17:02:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <3a7946e9-d178-f878-9774-64ff44bcf5df@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-06/txt/msg00043.txt.bz2 On 06/29/2017 05:53 PM, Pedro Alves wrote: > however, we'd need to still make "whatis" strip one level of > typedefs when the argument is a type, somehow, because we now > get this: > > (gdb) whatis zzz > type = zzz I suspect we can do that by making "whatis" look at the top of the expression tree, see if it's an OP_TYPE: (gdb) set debug expression 1 (gdb) whatis (zzz)0 ... Dump of expression @ 0x1bc6af0, after conversion to prefix form: Expression: `(zzz) 0' Language c, 8 elements, 16 bytes each. 0 UNOP_CAST_TYPE ( 1 OP_TYPE Type @0x18e7920 (zzz)) 4 OP_LONG Type @0x19a6650 (int), value 0 (0x0) type = zzz (gdb) whatis zzz ... Dump of expression @ 0x1bc87b0, after conversion to prefix form: Expression: `zzz' Language c, 3 elements, 16 bytes each. 0 OP_TYPE Type @0x18e7920 (zzz) type = zzz (gdb) whatis z ... Dump of expression @ 0x1bc6af0, after conversion to prefix form: Expression: `z' Language c, 4 elements, 16 bytes each. 0 OP_VAR_VALUE Block @0x19e8ee0, symbol @0x19e8e10 (z) type = zzz (gdb) There may be a helper for this already somewhere. I've never dug that much deeply into this area of the code. Thanks, Pedro Alves