From patchwork Tue Apr 9 16:36:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Marchi X-Patchwork-Id: 32222 Received: (qmail 104734 invoked by alias); 9 Apr 2019 16:37:02 -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 104668 invoked by uid 89); 9 Apr 2019 16:37:01 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-20.6 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mail.efficios.com Received: from mail.efficios.com (HELO mail.efficios.com) (167.114.142.138) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 09 Apr 2019 16:36:58 +0000 Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 128D37D08B; Tue, 9 Apr 2019 12:36:57 -0400 (EDT) Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10032) with ESMTP id tU_7OAkpVnVN; Tue, 9 Apr 2019 12:36:56 -0400 (EDT) Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 79EDB7D084; Tue, 9 Apr 2019 12:36:56 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 79EDB7D084 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1554827816; bh=oHxq9FDyz/fJOGGkM1Ox2cUFRt8X+54YfcdP00fVLhI=; h=To:From:Message-ID:Date:MIME-Version; b=H91JYuqjebaHWrGPmqtd1/NGf/t0mYxHJCPM5x2rcOj63NUDaZ40TA9gN7eNsHzVN 1uqxX2T/RzkZ3xJCpRxhuXnK2roKNikDRabBRlkwfMBpyemcfcPWIWbVy6IPWARPfh MVoeBs6Tz3DEEmWLvLibFo4rkBkQyM7GWuYQHHJ1UeAE+2AGXGkXcCJmcOXJVdTy1n ldphkqRKfWbNby8qaxzHJzkSJq7zsVMofxmhksYLwZsWrMsFvFrzeMQAZN7tnzImCQ i48678Tht68YiV/ZyzcmfxAY4nUqMJ+Up2gjzc4HUDfoq1i5UuSH9ocTNuEvLfuiOX Qwz3XwoQuE14g== Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10026) with ESMTP id EAptUlsDDSWX; Tue, 9 Apr 2019 12:36:56 -0400 (EDT) Received: from [172.16.0.120] (192-222-157-41.qc.cable.ebox.net [192.222.157.41]) by mail.efficios.com (Postfix) with ESMTPSA id 731DD7D07C; Tue, 9 Apr 2019 12:36:55 -0400 (EDT) Subject: Re: [PATCH] Use -qualified flag when setting temporary breakpoint in start command To: Pedro Alves , Simon Marchi , gdb-patches@sourceware.org References: <20190409025557.28846-1-simon.marchi@polymtl.ca> <4f78ab22-013e-9dba-6c3d-18c6a680c9a9@redhat.com> From: Simon Marchi Message-ID: <07dba943-b1b1-7160-78ff-8ed7d093a1c5@efficios.com> Date: Tue, 9 Apr 2019 12:36:54 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <4f78ab22-013e-9dba-6c3d-18c6a680c9a9@redhat.com> On 2019-04-09 12:30 p.m., Pedro Alves wrote: > On 4/9/19 5:19 PM, Simon Marchi wrote: > >> I had initially changed start.exp to test both C and C++, then decided to just >> keep C++ for simplicity. But your point about coverage is good, so I've done >> as you suggested. >> > > Thanks. > >> gdb/ChangeLog: >> >> * infcmd.c (run_command_1): Pass -qualified to tbreak when usind >> the "start" command. > > Typo "usind". Damn, I noticed this comment just after pushing. I fixed it in a follow up commit. >> >> gdb/testsuite/ChangeLog: >> >> * gdb.base/start-cpp.exp: New file. >> * gdb.base/start-cpp.cc: New file. > > Note start-cpp.cc wasn't included in this patch -- don't forget > to git add it. Ah, I think it's because I've renamed it from start-cpp.cpp at the last minute, when I noticed your comment about the extension. Here's what the definitive version I pushed (with start-cpp.cc included). Thanks for the review. Simon From e242fd1249ae85a97f08f95d5c61f4cbe3b906e0 Mon Sep 17 00:00:00 2001 From: Simon Marchi Date: Tue, 9 Apr 2019 12:32:26 -0400 Subject: [PATCH] Use -qualified flag when setting temporary breakpoint in start command When using the "start" command, GDB puts a temporary breakpoint on the "main" symbol (we literally invoke the tbreak command). However, since it does wild matching by default, it also puts a breakpoint on any C++ method or "main" function in a namespace. For example, when debugging GDB, it creates a total of 24 locations: (gdb) start Temporary breakpoint 1 at 0x198c1e9: main. (24 locations) as there are a bunch of methods called main in the selftests, such as selftests::string_view::capacity_1::main() If such method was called in the constructor of a global object, or a function marked with the attribute "constructor", then we would stop at the wrong place. Also, this causes a few extra symtabs (those that contain the "wrong" mains) to be expanded for nothing. The dummiest, most straightforward solution is to add -qualified when invoking tbreak. With this patch, "start" creates a single-location breakpoint, as expected. I copied the start.exp test to start-cpp.exp and made it use a C++ test file, which contains two main functions. The new test verifies that the output of "start" is the output we get when we set a single-location breakpoint. gdb/ChangeLog: * infcmd.c (run_command_1): Pass -qualified to tbreak when usind the "start" command. gdb/testsuite/ChangeLog: * gdb.base/start-cpp.exp: New file. * gdb.base/start-cpp.cc: New file. --- gdb/ChangeLog | 5 ++++ gdb/infcmd.c | 5 +++- gdb/testsuite/ChangeLog | 5 ++++ gdb/testsuite/gdb.base/start-cpp.cc | 33 +++++++++++++++++++++++++ gdb/testsuite/gdb.base/start-cpp.exp | 37 ++++++++++++++++++++++++++++ 5 files changed, 84 insertions(+), 1 deletion(-) create mode 100644 gdb/testsuite/gdb.base/start-cpp.cc create mode 100644 gdb/testsuite/gdb.base/start-cpp.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index e1d20fd4f20e..7af9b9047018 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2019-04-09 Simon Marchi + + * infcmd.c (run_command_1): Pass -qualified to tbreak when usind + the "start" command. + 2019-04-08 Kevin Buettner * python/py-inferior.c (infpy_thread_from_thread_handle): diff --git a/gdb/infcmd.c b/gdb/infcmd.c index 3b26fd4a4671..178f89e95207 100644 --- a/gdb/infcmd.c +++ b/gdb/infcmd.c @@ -604,7 +604,10 @@ run_command_1 (const char *args, int from_tty, enum run_how run_how) /* Insert temporary breakpoint in main function if requested. */ if (run_how == RUN_STOP_AT_MAIN) - tbreak_command (main_name (), 0); + { + std::string arg = string_printf ("-qualified %s", main_name ()); + tbreak_command (arg.c_str (), 0); + } exec_file = get_exec_file (0); diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 5f1ce3cb32d8..5c7cadf10a19 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2019-04-09 Simon Marchi + + * gdb.base/start-cpp.exp: New file. + * gdb.base/start-cpp.cc: New file. + 2019-04-08 Kevin Buettner * gdb.python/py-thrhandle.exp: Adjust tests to call diff --git a/gdb/testsuite/gdb.base/start-cpp.cc b/gdb/testsuite/gdb.base/start-cpp.cc new file mode 100644 index 000000000000..1d0fd7d323c9 --- /dev/null +++ b/gdb/testsuite/gdb.base/start-cpp.cc @@ -0,0 +1,33 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2019 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +namespace foo +{ + +int +main () +{ + return 1; +} + +} /* namespace foo */ + +int +main () +{ + return foo::main (); +} diff --git a/gdb/testsuite/gdb.base/start-cpp.exp b/gdb/testsuite/gdb.base/start-cpp.exp new file mode 100644 index 000000000000..5f98b92ffa41 --- /dev/null +++ b/gdb/testsuite/gdb.base/start-cpp.exp @@ -0,0 +1,37 @@ +# Copyright 2005-2019 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +standard_testfile .cc + +if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} { + return -1 +} + +# This is a testcase specifically for the `start' GDB command. For regular +# stop-in-main goal in the testcases consider using `runto_main' instead. + +# In this C++ version of the test (as opposed to start.exp), we specifically +# test that the temporary breakpoint created by the start command has a single +# location, even if we have a function named "main" in a non-root namespace. + +# For C++ programs, "start" should stop in main(). +if { [gdb_start_cmd] < 0 } { + untested start + return -1 +} + +gdb_test "" \ + "Temporary breakpoint $decimal at $hex: file.*main \\(\\) at .*start-cpp.cc:.*" \ + "start"