From patchwork Thu Mar 9 09:43:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Preudhomme X-Patchwork-Id: 736916 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 3vf5764wr3z9s76 for ; Thu, 9 Mar 2017 20:43:28 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.b="fd4ucqfj"; 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 :subject:to:references:cc:from:message-id:date:mime-version :in-reply-to:content-type; q=dns; s=default; b=l2KplfOr5NgNNiPzX EQHf9+yaQDyYYc3CO3erxkpjJ7wLvHCsd07seHdE+psp/uS/NUkxH71yeYSYAtTA i0w4LXKC8xFf9w2nuknUU5vU8QXEeynujKswWJEoyGvoAylT06c0PmmEGNbtnChr AlDGVuNiiWbksWFHTOFe2xzBSA= 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 :subject:to:references:cc:from:message-id:date:mime-version :in-reply-to:content-type; s=default; bh=DQZCjIC5ZAK3D2MMI6CAxAv Fj2Y=; b=fd4ucqfjZu/Fr8pWvDrt6o1PZ5M84kaCe4yLoUdvbp8i7pESnySy2gS FmRzdhq1zMjmhyy6k5qWoFfGCbEQA42iTmQCiqAobGzwkUg3qrBup3Cf7pAI6sQb bmTzHwGiEy8sCgvtyPXifNetV9Q7pt8g5pBRWh7L22Mo+SPt8F0U= Received: (qmail 51730 invoked by alias); 9 Mar 2017 09:43:20 -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 50048 invoked by uid 89); 9 Mar 2017 09:43:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-25.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_LAZY_DOMAIN_SECURITY, KAM_LOTSOFHASH, KAM_STOCKGEN, RP_MATCHES_RCVD autolearn=ham version=3.3.2 spammy=twofold, Best X-HELO: foss.arm.com Received: from foss.arm.com (HELO foss.arm.com) (217.140.101.70) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 09 Mar 2017 09:43:17 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7A8CC344; Thu, 9 Mar 2017 01:43:16 -0800 (PST) Received: from [10.2.206.52] (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CE1513F3E1; Thu, 9 Mar 2017 01:43:15 -0800 (PST) Subject: Re: [PATCH, GCC/LTO] Fix PR69866: LTO with def for weak alias in regular object file To: Richard Biener , "gcc-patches@gcc.gnu.org" References: <654b4277-ced9-e778-bcda-3054e1983727@foss.arm.com> Cc: Jan Hubicka From: Thomas Preudhomme Message-ID: <1db1d20c-6f06-9bd3-2e7d-e862e31199cd@foss.arm.com> Date: Thu, 9 Mar 2017 09:43:13 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <654b4277-ced9-e778-bcda-3054e1983727@foss.arm.com> X-IsSubscribed: yes Ping? Best regards, Thomas On 02/03/17 14:51, Thomas Preudhomme wrote: > Hi, > > This patch fixes an assert failure when linking one LTOed object file > having a weak alias with a regular object file containing a strong > definition for that same symbol. The patch is twofold: > > + do not add an alias to a partition if it is external > + do not declare (.globl) an alias if it is external > > ChangeLog entries are as follow: > > *** gcc/lto/ChangeLog *** > > 2017-03-01 Thomas Preud'homme > > PR lto/69866 > * lto/lto-partition.c (add_symbol_to_partition_1): Do not add external > aliases to partition. > > *** gcc/ChangeLog *** > > 2017-03-01 Thomas Preud'homme > > PR lto/69866 > * cgraphunit.c (cgraph_node::assemble_thunks_and_aliases): Do not > declare external aliases. > > *** gcc/testsuite/ChangeLog *** > > 2017-02-28 Thomas Preud'homme > > PR lto/69866 > * gcc.dg/lto/pr69866_0.c: New test. > * gcc.dg/lto/pr69866_1.c: Likewise. > > > Testing: Testsuite shows no regression when targeting Cortex-M3 with an > arm-none-eabi GCC cross-compiler, neither does it show any regression with > native LTO-bootstrapped x86-64_linux-gnu and aarch64-linux-gnu compilers. > > Is this ok for stage4? > > Best regards, > > Thomas diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c index c82a88a599ca61b068dd9783d2a6158163809b37..580500ff922b8546d33119261a2455235edbf16d 100644 --- a/gcc/cgraphunit.c +++ b/gcc/cgraphunit.c @@ -1972,7 +1972,7 @@ cgraph_node::assemble_thunks_and_aliases (void) FOR_EACH_ALIAS (this, ref) { cgraph_node *alias = dyn_cast (ref->referring); - if (!alias->transparent_alias) + if (!alias->transparent_alias && !DECL_EXTERNAL (alias->decl)) { bool saved_written = TREE_ASM_WRITTEN (decl); diff --git a/gcc/lto/lto-partition.c b/gcc/lto/lto-partition.c index e27d0d1690c1fcfb39e2fac03ce0f4154031fc7c..f44fd435ed075a27e373bdfdf0464eb06e1731ef 100644 --- a/gcc/lto/lto-partition.c +++ b/gcc/lto/lto-partition.c @@ -178,7 +178,8 @@ add_symbol_to_partition_1 (ltrans_partition part, symtab_node *node) /* Add all aliases associated with the symbol. */ FOR_EACH_ALIAS (node, ref) - if (!ref->referring->transparent_alias) + if (!ref->referring->transparent_alias + && ref->referring->get_partitioning_class () != SYMBOL_EXTERNAL) add_symbol_to_partition_1 (part, ref->referring); else { @@ -189,7 +190,8 @@ add_symbol_to_partition_1 (ltrans_partition part, symtab_node *node) { /* Nested transparent aliases are not permitted. */ gcc_checking_assert (!ref2->referring->transparent_alias); - add_symbol_to_partition_1 (part, ref2->referring); + if (ref2->referring->get_partitioning_class () != SYMBOL_EXTERNAL) + add_symbol_to_partition_1 (part, ref2->referring); } } diff --git a/gcc/testsuite/gcc.dg/lto/pr69866_0.c b/gcc/testsuite/gcc.dg/lto/pr69866_0.c new file mode 100644 index 0000000000000000000000000000000000000000..f49ef8d4c1da7a21d1bfb5409d647bd18141595b --- /dev/null +++ b/gcc/testsuite/gcc.dg/lto/pr69866_0.c @@ -0,0 +1,13 @@ +/* { dg-lto-do link } */ + +int _umh(int i) +{ + return i+1; +} + +int weaks(int i) __attribute__((weak, alias("_umh"))); + +int main() +{ + return weaks(10); +} diff --git a/gcc/testsuite/gcc.dg/lto/pr69866_1.c b/gcc/testsuite/gcc.dg/lto/pr69866_1.c new file mode 100644 index 0000000000000000000000000000000000000000..3a14f850eefaffbf659ce4642adef7900330f4ed --- /dev/null +++ b/gcc/testsuite/gcc.dg/lto/pr69866_1.c @@ -0,0 +1,6 @@ +/* { dg-options { -fno-lto } } */ + +int weaks(int i) +{ + return i+1; +}