From patchwork Wed Feb 24 18:35:58 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Wakely X-Patchwork-Id: 587579 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 8F3D0140322 for ; Thu, 25 Feb 2016 05:36:18 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.b=dNddvMEj; dkim-atps=neutral DomainKey-Signature: a=rsa-sha1; c=nofws; d=gcc.gnu.org; h=list-id :list-unsubscribe:list-archive:list-post:list-help:sender:date :from:to:cc:subject:message-id:mime-version:content-type; q=dns; s=default; b=vbJ1cWMtQrg1+NKmq+KTbEkkiJxCEDXyQdrIPUUV0vZg7sNj4g eBk3u6lDMosu9Aq5yxAAG9P+eswbMZhPVRVgOUGEMh2vXakGBifduilbRYfwcENh HbMjVdy0sDTNi+1K2NXEf7/hPmIMScxI2t0Ni+ImzL2498splIejctIYQ= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=gcc.gnu.org; h=list-id :list-unsubscribe:list-archive:list-post:list-help:sender:date :from:to:cc:subject:message-id:mime-version:content-type; s= default; bh=9UcYwWsQHnSFqrzKEvHLk+DQedQ=; b=dNddvMEjUosA2Y9G0NLX TWdsuVvTTTah4Ya1ldWVKPC7mObK8geeonYwt5kr3slfKtoSgIMZGVCRJHTVuu1k jvvRWg8eU9y9wkzYIkwd2l9CO+9F/5jVoy9ASas6bML7AOSXp4y82WKd+BO4qdoE B7rPfpRpfi8Z58g7F+o8Fa8= Received: (qmail 128363 invoked by alias); 24 Feb 2016 18:36:02 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org Received: (qmail 128326 invoked by uid 89); 24 Feb 2016 18:36:02 -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=deallocate, 1108, 18_support, pools 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 (AES256-GCM-SHA384 encrypted) ESMTPS; Wed, 24 Feb 2016 18:36:00 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 70D1764366; Wed, 24 Feb 2016 18:35:59 +0000 (UTC) Received: from localhost (ovpn-116-70.ams2.redhat.com [10.36.116.70]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u1OIZwj3021135; Wed, 24 Feb 2016 13:35:59 -0500 Date: Wed, 24 Feb 2016 18:35:58 +0000 From: Jonathan Wakely To: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org Cc: Ivo Raisr , Mark Wielaard Subject: [patch] libstdc++/69945 Add __gnu_cxx::__freeres hook Message-ID: <20160224183558.GF4664@redhat.com> MIME-Version: 1.0 Content-Disposition: inline X-Clacks-Overhead: GNU Terry Pratchett User-Agent: Mutt/1.5.24 (2015-08-30) This adds a new function to libsupc++ which will free the memory still in use by the pool used for allocating exceptions when malloc fails. This is similar to glibc's __libc_freeres, which valgrind (and other tools?) use to tell glibc to deallocate everything before exiting. I initially called it __gnu_cxx::__free_eh_pool() but I figured we might have other memory in use at some later date, and we wouldn't want valgrind to have to start calling a second function, nor make a function called __free_eh_pool() actually free other things. I intentionally *didn't* lock the pool's mutex before freeing it, because this should never be called in a context where multiple threads are still active and accessing the pool. Thoughts? Is the new test a good idea, or will exposing it like that in the testsuite just give users the idea that they can/should be doing the same themselves? [ Aside: should the actual pool be created with placement-new to [ ensure it doesn't ever get destroyed? [ [ alignas(pool) unsigned char poolbuf[sizeof(pool)]; [ pool& emergency_pool = *::new(poolbuf) pool; commit 40fed1db72b0a4852d5890c2c464a0baabb02b74 Author: Jonathan Wakely Date: Wed Feb 24 18:22:30 2016 +0000 libstdc++/69945 Add __gnu_cxx::__freeres hook * config/abi/pre/gnu.ver: Add new symbol. * libsupc++/eh_alloc.cc (__gnu_cxx::__freeres): Define. * testsuite/18_support/free_eh_pool.cc: New test. diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver index 41069d1..5c6b0fe 100644 --- a/libstdc++-v3/config/abi/pre/gnu.ver +++ b/libstdc++-v3/config/abi/pre/gnu.ver @@ -2148,6 +2148,8 @@ CXXABI_1.3.10 { _ZGTtNKSt13bad_exceptionD1Ev; _ZGTtNKSt13bad_exception4whatEv; + _ZN9__gnu_cxx9__freeresEv; + } CXXABI_1.3.9; # Symbols in the support library (libsupc++) supporting transactional memory. diff --git a/libstdc++-v3/libsupc++/eh_alloc.cc b/libstdc++-v3/libsupc++/eh_alloc.cc index 6973af3..d362e40 100644 --- a/libstdc++-v3/libsupc++/eh_alloc.cc +++ b/libstdc++-v3/libsupc++/eh_alloc.cc @@ -73,6 +73,10 @@ using namespace __cxxabiv1; # define EMERGENCY_OBJ_COUNT 4 #endif +namespace __gnu_cxx +{ + void __freeres(); +} namespace { @@ -106,6 +110,8 @@ namespace // to implement in_pool. char *arena; std::size_t arena_size; + + friend void __gnu_cxx::__freeres(); }; pool::pool() @@ -244,6 +250,19 @@ namespace pool emergency_pool; } +namespace __gnu_cxx +{ + void + __freeres() + { + if (emergency_pool.arena) + { + ::free(emergency_pool.arena); + emergency_pool.arena = 0; + } + } +} + extern "C" void * __cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) _GLIBCXX_NOTHROW { diff --git a/libstdc++-v3/testsuite/18_support/free_eh_pool.cc b/libstdc++-v3/testsuite/18_support/free_eh_pool.cc new file mode 100644 index 0000000..9712d3d --- /dev/null +++ b/libstdc++-v3/testsuite/18_support/free_eh_pool.cc @@ -0,0 +1,35 @@ +// Copyright (C) 2016 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library 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, or (at your option) +// any later version. + +// This library 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 library; see the file COPYING3. If not see +// . + +// { dg-do run } + +namespace __gnu_cxx { + void __freeres(); +} + +struct X { + ~X() { + __gnu_cxx::__freeres(); + } +}; + +X x; + +int +main() +{ +}