From patchwork Tue Oct 17 16:12:16 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pedro Alves X-Patchwork-Id: 23646 Received: (qmail 117377 invoked by alias); 17 Oct 2017 16:12:20 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 117362 invoked by uid 89); 17 Oct 2017 16:12:20 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:1658 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; Tue, 17 Oct 2017 16:12:19 +0000 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CBDA433A196; Tue, 17 Oct 2017 16:12:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com CBDA433A196 Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=palves@redhat.com 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 2A70378004; Tue, 17 Oct 2017 16:12:16 +0000 (UTC) Subject: Re: Sporadic failures of selftest tests To: Ulrich Weigand References: <20171017154758.DD85FD807C2@oc3748833570.ibm.com> <30d4dc25-a59b-1196-3bc3-c8b982191ec0@redhat.com> Cc: gdb-patches@sourceware.org From: Pedro Alves Message-ID: Date: Tue, 17 Oct 2017 17:12:16 +0100 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: <30d4dc25-a59b-1196-3bc3-c8b982191ec0@redhat.com> On 10/17/2017 04:54 PM, Pedro Alves wrote: > Commit bf4692711232 ("Eliminate catch_errors") also did this: > > @@ -1145,7 +1142,15 @@ captured_main (void *data) > change - SET_TOP_LEVEL() - has been eliminated. */ > while (1) > { > - catch_errors (captured_command_loop, 0, "", RETURN_MASK_ALL); > + TRY > + { > + captured_command_loop (); > + } > + CATCH (ex, RETURN_MASK_ALL) > + { > + exception_print (gdb_stderr, ex); > + } > + END_CATCH > } > > So most probably before that commit captured_command_loop > wasn't inlined in captured main (unless LTO, maybe). Probably the best fix would be to move away from selftest entirely and convert them to unit tests instead. Meanwhile, how about this as an easy fix? We could try playing games with making functions extern, but maybe that'd break again with LTO. Seems to work for gdb.gdb/selftest.exp and gdb.gdb/complaints.exp at least. (I think we can use __attribute__ directly because include/ansidecl.h defines it to empty on non-gcc or older gccs.) From: Pedro Alves Date: 2017-10-17 15:04:11 +0100 prevent inlining captured_command_loop --- gdb/main.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/gdb/main.c b/gdb/main.c index beb8203..a60cd50 100644 --- a/gdb/main.c +++ b/gdb/main.c @@ -307,6 +307,11 @@ setup_alternate_signal_stack (void) /* Call command_loop. */ +/* Prevent inlining this function for the benefit of gdb's selftests + in the testsuite. Those tests want to run GDB under GDB and stop + here. */ +static void captured_command_loop () __attribute__((noinline)); + static void captured_command_loop () {