From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F31C4C77B7A for ; Tue, 16 May 2023 19:14:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229524AbjEPTON convert rfc822-to-8bit (ORCPT ); Tue, 16 May 2023 15:14:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43642 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229464AbjEPTOM (ORCPT ); Tue, 16 May 2023 15:14:12 -0400 Received: from secure.elehost.com (secure.elehost.com [185.209.179.11]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E5795264 for ; Tue, 16 May 2023 12:14:10 -0700 (PDT) X-Virus-Scanned: Debian amavisd-new at secure.elehost.com Received: from Mazikeen (cpebc4dfb928313-cmbc4dfb928310.cpe.net.cable.rogers.com [99.228.251.108] (may be forged)) (authenticated bits=0) by secure.elehost.com (8.15.2/8.15.2/Debian-22ubuntu3) with ESMTPSA id 34GJCnPT2497732 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 16 May 2023 19:12:49 GMT Reply-To: From: To: "'Junio C Hamano'" , "'Taylor Blau'" Cc: , "'Randall S. Becker'" , "'Elijah Newren'" References: In-Reply-To: Subject: RE: [PATCH] run-command.c: fix missing include under `NO_PTHREADS` Date: Tue, 16 May 2023 15:13:57 -0400 Organization: Nexbridge Inc. Message-ID: <00a601d9882a$93c7a940$bb56fbc0$@nexbridge.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Mailer: Microsoft Outlook 16.0 Thread-Index: AQHsJJn1ilZfYkryfQksEiQudd2gtgElbtoOAqjywXmvGZjBIA== Content-Language: en-ca Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tuesday, May 16, 2023 3:12 PM, Junio C Hamano wrote: >Taylor Blau writes: > >> When building git with `NO_PTHREADS=YesPlease`, we fail to build >> run-command.o since we don't have a definition for ALLOC_GROW: >> >> $ make NO_PTHREADS=1 DEVELOPER=1 run-command.o >> GIT_VERSION = 2.41.0.rc0.1.g787eb3beae.dirty >> CC run-command.o >> run-command.c: In function ‘git_atexit’: >> run-command.c:1103:9: error: implicit declaration of function ‘ALLOC_GROW’ [- >Werror=implicit-function-declaration] >> 1103 | ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, >git_atexit_hdlrs.alloc); >> | ^~~~~~~~~~ >> cc1: all warnings being treated as errors >> make: *** [Makefile:2715: run-command.o] Error 1 > >I am OK to give a reproduction recipe, i.e. the "$ make" command line, to make it >easy for people, who cannot remember how to define make variables from the >command line, to try out themselves, but I hate the "build transcript" in the log >message, when a few lines of prose suffices. > >How about this? > > Git 2.41-rc0 fails to compile run-command.c with NO_PTHREADS > defined, i.e. > > $ make NO_PTHREADS=1 run-command.o > > as ALLOC_GROW() macro is used in the atexit() emulation but the > macro definition is not available. > >> This bisects to 36bf195890 (alloc.h: move ALLOC_GROW() functions from >> cache.h, 2023-02-24), which replaced includes of "cache.h" with >> "alloc.h", which is the new home of `ALLOC_GROW()` (and >> `ALLOC_GROW_BY()`). > >Good. >Insert something like: > > We can see that run-command.c is the only one that try to use > these macros without including . > > $ git grep -l -e '[^_]ALLOC_GROW(' -e 'ALLOC_GROW_BY(' \*.c | sort >/tmp/1 > $ git grep -l 'alloc\.h' \*.c | sort >/tmp/2 > $ comm -23 /tmp/[12] > compat/simple-ipc/ipc-unix-socket.c > run-command.c > > The "compat/" file only talks about the macro in the comment, > and is not broken. > >here. What I am aiming for is to tell readers what they do not have to spend their >time on. As we encourage people to make sure to look for other errors that come >from the same root cause when making a fix, avoiding duplicated work by telling >what they do not have to look at is rather important. > >> run-command.c compiles fine when `NO_PTHREADS` is undefined, since its >> use of `ALLOC_GROW()` is behind a `#ifndef NO_PTHREADS`. (Everything >> else compiles fine when NO_PTHREADS is defined, so this is the only >> spot that needs fixing). > >I think we can say that, but is probably coered by the three-line summary I gave >above. > >> We could fix this by conditionally including "alloc.h" when >> `NO_PTHREADS` is defined. But we have relatively few examples of >> conditional includes throughout the tree[^1]. >> >> Instead, include "alloc.h" unconditionally in run-command.c to allow >> it to successfully compile even when NO_PTHREADS is defined. > >Good. > >> [^1]: With `git grep -E -A1 '#if(n)?def' -- **/*.c | grep '#include' -B1`. > >Good. This all makes sense to me.