From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by sourceware.org (Postfix) with ESMTPS id 6CFA33858402 for ; Mon, 13 Sep 2021 19:06:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 6CFA33858402 Received: by mail-pg1-x52c.google.com with SMTP id h3so10352020pgb.7 for ; Mon, 13 Sep 2021 12:06:22 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=awAoXqEOKFV5Z02qZ4PaT1usuN7o/CrN8zRpfSmqziw=; b=Vx5f68y5dCJUqllaavhbB75qXRgRPII8jLh8bC0lPxXo2ba1edqZh9Xmp/kHyv0GU+ IgO00QlPk7TATOKCnyyRvbaWTbrUIO0GJsOfSFQ4UZSkuI05kYju0V6rbyy4mdlh0/TJ PbrRV8hMFDNshYirylEuoQBPa1Fk2qNoUzo5CbXYlrzW6vAoyc9jfZwC5EFDRifZ9KEX XZ/3jPmDOfxnAJpVKH5xDvm21hpAXdOU0KYlLVBwve1qdXNvo+9tZLgTplSuIOxGBNwW RvGjfuq9OKj/vIvMyBDPaDdESe4RaUmAGj6uurKJEW7Swx82aCItTJNuFQyGrExhmuxi hr3A== X-Gm-Message-State: AOAM5319wOPpOAdv5bxZx0gr+noDwaSp9xzeUfSRsf/mS3xxNxWmzzkr Vq5njBjBWLvRRvsXadU3kjs= X-Google-Smtp-Source: ABdhPJwkXFx1AtG7106cTyq+wecPwOjjYnnnkRj+w8x17orpQMaWxzy5JmdlGiNWkkjsibkkqOMQKw== X-Received: by 2002:a62:7985:0:b0:437:36f1:d0df with SMTP id u127-20020a627985000000b0043736f1d0dfmr880149pfc.52.1631559981428; Mon, 13 Sep 2021 12:06:21 -0700 (PDT) Received: from [172.31.0.175] (c-98-202-48-222.hsd1.ut.comcast.net. [98.202.48.222]) by smtp.gmail.com with ESMTPSA id n38sm2763982pfv.198.2021.09.13.12.06.20 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 13 Sep 2021 12:06:21 -0700 (PDT) Subject: Re: [PATCH][v2] Always default to DWARF2_DEBUG if not specified, warn about deprecated STABS To: "Koning, Paul" , Richard Guenther Cc: GCC Patches , Andreas Schwab , "dave.anglin@bell.net" , "ni1d@arrl.net" References: <66161527-98n2-3060-49ss-67oro67381nq@fhfr.qr> <0E74A665-3565-4E4A-8DD8-D9883EE14C49@dell.com> From: Jeff Law Message-ID: <81f5fede-d55a-da9b-aca7-3f461d4d32b3@gmail.com> Date: Mon, 13 Sep 2021 13:06:19 -0600 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <0E74A665-3565-4E4A-8DD8-D9883EE14C49@dell.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Spam-Status: No, score=-3.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Sep 2021 19:06:23 -0000 On 9/13/2021 10:52 AM, Koning, Paul wrote: > >> On Sep 13, 2021, at 3:31 AM, Richard Biener wrote: >> >> This makes defaults.h choose DWARF2_DEBUG if PREFERRED_DEBUGGING_TYPE >> is not specified by the target and NO_DEBUG if DWARF is not supported. >> >> It also makes us warn when STABS is enabled and removes the corresponding >> diagnostic from the Ada frontend. The warnings are pruned from the >> testsuite output via prune_gcc_output. >> >> This leaves the following targets without debug support: >> >> pdp11-*-* pdp11 is a.out, dwarf support is difficult > I'll admit that I don't know much about debug formats. It is definitely the case that pdp11 output is a.out (it may be BSD 2.x style a.out -- which I think is somewhat different though it's been many years since I looked at that, and then only briefly). I guess that constrains which debug formats can be used, but I don't know any details. My recollection of aout stabs is mostly lost.  IIRC we'd emit .stabs directives to the assembler which would turn into symbol table entries. Embedded stabs used the same underlying stab strings, but instead put the information into a special section.  That requires an object format that supports named sections, so it's a non-starter for a.out. dwarf also requires named sections.  While in theory one could probably do something hackish like dwarf embedded in .stab directives, that just seems just awful. > > pdp11-elf was done as an experiment by someone else, in binutils. I'll ask about the status of that. If it's possible to deliver that, it would presumably enable DWARF support. Is that all common code so it's a matter of enabling it, or would "DWARF machine details for pdp11" have to be defined? That's going to be the best path forward.  Get the pdp11-elf bits working and the dwarf2 debugging stuff should come along for free. Jeff