Message ID | 20201228194855.510315-3-maskray@google.com |
---|---|
State | Superseded |
Delegated to: | Carlos O'Donell |
Headers |
Return-Path: <libc-alpha-bounces@sourceware.org> X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 3D41B3875414; Mon, 28 Dec 2020 19:49:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3D41B3875414 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1609184950; bh=iLNXrLXzW6YJVpPHP1sLs0ZvCN1QLQq+/LnEnypZU1g=; h=Date:In-Reply-To:References:Subject:To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=WGbxngy6Uq3YsJYWWD3HAbHrbDCqrc1AX+mq0kyryDY662rOy3CLqR7vpQer2GpPi TOLkAZxi+gUsV1wm8bnEkRfTc53Lp1yLn+70c2QWiT0is3VuSrqCnpsWQPMGWWBj/5 wubIUXBRI9rIfCxQpvnLwyJ3U50m1mMgsUuahdp4= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by sourceware.org (Postfix) with ESMTPS id 688553861887 for <libc-alpha@sourceware.org>; Mon, 28 Dec 2020 19:49:08 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 688553861887 Received: by mail-yb1-xb49.google.com with SMTP id k7so19694222ybm.13 for <libc-alpha@sourceware.org>; Mon, 28 Dec 2020 11:49:08 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=iLNXrLXzW6YJVpPHP1sLs0ZvCN1QLQq+/LnEnypZU1g=; b=lrmLBW1jpI+U+sI/kEJfAi8JFG4q7cTrrWzUEH/G0j6a/+s6ACeYmB6fcrUOXPxMgH E5wypQ9mignPDx+vp5mjcMD7n0P0uUnMCxERLRJGwvNdqRVzFF0eYoKZf9lmUzrPWlOV CGo4XEM2QyA4u+KArl2HeALSXK7LkDGXuTtBjHnHTf41UKtb1Ej3sU1Ts6+OwWxaDyTw K3LXoF7HraKhtQgp+jleN3VhBuAoNFsZo09Eol20cZdDSbr39gfTKXQbdkimfYS9cN83 LOKtUmagzHUpo5s1QSNbFjluSVFAbsZC+Ew9XCvCLX/2CVKFq6lnSCXnHQiK5XLcqfql XcUg== X-Gm-Message-State: AOAM532Lf0sXwFog0ySEsErO/Qg2w9NovKm1j7On07zzL2k9Q03q4ppn 7AWnI0IhVCZN6zYn6+VKuECNABY5qO6rGya4G3vQa3r4jygAmmcWIlJb6RyvFiEnS23VCnMlYUf 4tooCW6NhZmrg3M2R0Pr3pEmIFUJqL7GALK4zbUOzY+UBMeRrhZQCOf8jCD/fV7hf4SEw X-Google-Smtp-Source: ABdhPJwHsZamxSIwy6WCcJUDaTO/HsSQVB3lDY5DYlOdB4iOkAfk2rTCfjC3uDvx5aXL1JpgJtSL+Ja7EMot X-Received: from maskray1.svl.corp.google.com ([2620:15c:2ce:0:a6ae:11ff:fe11:4abb]) (user=maskray job=sendgmr) by 2002:a25:aa45:: with SMTP id s63mr66032979ybi.471.1609184947926; Mon, 28 Dec 2020 11:49:07 -0800 (PST) Date: Mon, 28 Dec 2020 11:48:54 -0800 In-Reply-To: <20201228194855.510315-1-maskray@google.com> Message-Id: <20201228194855.510315-3-maskray@google.com> Mime-Version: 1.0 References: <20201228194855.510315-1-maskray@google.com> X-Mailer: git-send-email 2.29.2.729.g45daf8777d-goog Subject: [PATCH 2/3] elf: Replace a --defsym trick with an object file to be compatible with lld To: libc-alpha@sourceware.org Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-19.9 required=5.0 tests=BAYES_00, DKIMWL_WL_MED, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list <libc-alpha.sourceware.org> List-Unsubscribe: <https://sourceware.org/mailman/options/libc-alpha>, <mailto:libc-alpha-request@sourceware.org?subject=unsubscribe> List-Archive: <https://sourceware.org/pipermail/libc-alpha/> List-Post: <mailto:libc-alpha@sourceware.org> List-Help: <mailto:libc-alpha-request@sourceware.org?subject=help> List-Subscribe: <https://sourceware.org/mailman/listinfo/libc-alpha>, <mailto:libc-alpha-request@sourceware.org?subject=subscribe> From: Fangrui Song via Libc-alpha <libc-alpha@sourceware.org> Reply-To: Fangrui Song <maskray@google.com> Cc: Fangrui Song <maskray@google.com> Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" <libc-alpha-bounces@sourceware.org> |
Series |
Make glibc build with LLD
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Commit Message
Fangrui Song
Dec. 28, 2020, 7:48 p.m. UTC
The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os definitions before libc_pic.a so that libc_pic.a(malloc.os) is not fetched. This trick is used to avoid multiple definition errors which would happen as a chain result: dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free free fetches libc_pic.a(malloc.os) libc_pic.a(malloc.os) has an undefined __libc_message __libc_message fetches libc_pic.a(libc_fatal.os) libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) >>> defined at dl-fxstatat64.c >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) >>> defined at libc_fatal.c >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a lld processes --defsym after all input files, so this trick does not suppress multiple definition errors with lld. Split the step into two and use an object file to make the intention more obvious and make lld work. This is conceptually more appropriate because --defsym defines a SHN_ABS symbol while a normal definition is relative to the image base. See https://sourceware.org/pipermail/libc-alpha/2020-March/111910.html for discussions about the --defsym semantics. --- elf/Makefile | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
Comments
On Mon, Dec 28, 2020 at 11:49 AM Fangrui Song <maskray@google.com> wrote: > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > fetched. This trick is used to avoid multiple definition errors which > would happen as a chain result: > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > free fetches libc_pic.a(malloc.os) > libc_pic.a(malloc.os) has an undefined __libc_message > __libc_message fetches libc_pic.a(libc_fatal.os) > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > >>> defined at dl-fxstatat64.c > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > >>> defined at libc_fatal.c > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > lld processes --defsym after all input files, so this trick does not > suppress multiple definition errors with lld. Split the step into two > and use an object file to make the intention more obvious and make lld > work. > > This is conceptually more appropriate because --defsym defines a SHN_ABS > symbol while a normal definition is relative to the image base. > > See https://sourceware.org/pipermail/libc-alpha/2020-March/111910.html > for discussions about the --defsym semantics. > --- > elf/Makefile | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) Ping on this
On Mon, Jan 11, 2021 at 12:06 PM Fāng-ruì Sòng <maskray@google.com> wrote: > > On Mon, Dec 28, 2020 at 11:49 AM Fangrui Song <maskray@google.com> wrote: > > > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > > fetched. This trick is used to avoid multiple definition errors which > > would happen as a chain result: > > > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > > free fetches libc_pic.a(malloc.os) > > libc_pic.a(malloc.os) has an undefined __libc_message > > __libc_message fetches libc_pic.a(libc_fatal.os) > > > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > > >>> defined at dl-fxstatat64.c > > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > > >>> defined at libc_fatal.c > > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > > > lld processes --defsym after all input files, so this trick does not > > suppress multiple definition errors with lld. Split the step into two > > and use an object file to make the intention more obvious and make lld > > work. > > > > This is conceptually more appropriate because --defsym defines a SHN_ABS > > symbol while a normal definition is relative to the image base. > > > > See https://sourceware.org/pipermail/libc-alpha/2020-March/111910.html > > for discussions about the --defsym semantics. > > --- > > elf/Makefile | 11 ++++------- > > 1 file changed, 4 insertions(+), 7 deletions(-) > > Ping on this PING^2 https://sourceware.org/pipermail/libc-alpha/2020-December/121144.html You can also find the commit in https://sourceware.org/git/?p=glibc.git;a=shortlog;h=refs/heads/maskray/lld
On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha <libc-alpha@sourceware.org> wrote: > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > fetched. This trick is used to avoid multiple definition errors which > would happen as a chain result: > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > free fetches libc_pic.a(malloc.os) > libc_pic.a(malloc.os) has an undefined __libc_message > __libc_message fetches libc_pic.a(libc_fatal.os) > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > >>> defined at dl-fxstatat64.c > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > >>> defined at libc_fatal.c > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > lld processes --defsym after all input files, so this trick does not > suppress multiple definition errors with lld. Split the step into two > and use an object file to make the intention more obvious and make lld > work. > > This is conceptually more appropriate because --defsym defines a SHN_ABS > symbol while a normal definition is relative to the image base. > This is irrelevant since --defsym was used to create a temporary file which was removed immediately after it was created: /usr/bin/gcc -nostdlib -nostartfiles -r -o /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 -Wl,--defsym=__stack_chk_fail_local=0 \ '-Wl,-(' /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > --- > elf/Makefile | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) > > diff --git a/elf/Makefile b/elf/Makefile > index 0b4d78c874..299bf24b49 100644 > --- a/elf/Makefile > +++ b/elf/Makefile > @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > malloc \ > realloc \ > > -# The GCC arguments that implement $(rtld-stubbed-symbols). > -rtld-stubbed-symbols-args = \ > - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > - > ifeq ($(have-ssp),yes) > # rtld is not built with the stack protector, so these references will > # go away in the rebuilds. > @@ -536,9 +532,10 @@ endif > > $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > @-rm -f $@T > - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > - rm -f $@.o > + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - Please generate .globl symbol; symbol = 0; to make it closer to -Wl,--defsym=symbol=0. > + $(reloc-link) -o $@.o $@T.o '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > + rm -f %@T.o $@.o > mv -f $@T $@ > > # For lld, skip preceding addresses and values before matching the archive and the member. > -- > 2.29.2.729.g45daf8777d-goog >
On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha > <libc-alpha@sourceware.org> wrote: > > > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > > fetched. This trick is used to avoid multiple definition errors which > > would happen as a chain result: > > > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > > free fetches libc_pic.a(malloc.os) > > libc_pic.a(malloc.os) has an undefined __libc_message > > __libc_message fetches libc_pic.a(libc_fatal.os) > > > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > > >>> defined at dl-fxstatat64.c > > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > > >>> defined at libc_fatal.c > > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > > > lld processes --defsym after all input files, so this trick does not > > suppress multiple definition errors with lld. Split the step into two > > and use an object file to make the intention more obvious and make lld > > work. > > > > This is conceptually more appropriate because --defsym defines a SHN_ABS > > symbol while a normal definition is relative to the image base. > > > > This is irrelevant since --defsym was used to create a temporary file which was > removed immediately after it was created: > > /usr/bin/gcc -nostdlib -nostartfiles -r -o > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 > -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 > -Wl,--defsym=__stack_chk_fail_local=0 \ > '-Wl,-(' > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a > -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > > > --- > > elf/Makefile | 11 ++++------- > > 1 file changed, 4 insertions(+), 7 deletions(-) > > > > diff --git a/elf/Makefile b/elf/Makefile > > index 0b4d78c874..299bf24b49 100644 > > --- a/elf/Makefile > > +++ b/elf/Makefile > > @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > > malloc \ > > realloc \ > > > > -# The GCC arguments that implement $(rtld-stubbed-symbols). > > -rtld-stubbed-symbols-args = \ > > - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > > - > > ifeq ($(have-ssp),yes) > > # rtld is not built with the stack protector, so these references will > > # go away in the rebuilds. > > @@ -536,9 +532,10 @@ endif > > > > $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > > @-rm -f $@T > > - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > > - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > > - rm -f $@.o > > + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > > + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - > > Please generate > > .globl symbol; > symbol = 0; > > to make it closer to -Wl,--defsym=symbol=0. If symbol: and symbol = 0; work, isn't symbol: slightly better because it looks more normal? Or is the intention here using SHN_ABS to make it clear these symbols are special? > > + $(reloc-link) -o $@.o $@T.o '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > > + rm -f %@T.o $@.o > > mv -f $@T $@ > > > > # For lld, skip preceding addresses and values before matching the archive and the member. > > -- > > 2.29.2.729.g45daf8777d-goog > > > > > -- > H.J.
On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: > > On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > > > On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha > > <libc-alpha@sourceware.org> wrote: > > > > > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > > > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > > > fetched. This trick is used to avoid multiple definition errors which > > > would happen as a chain result: > > > > > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > > > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > > > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > > > free fetches libc_pic.a(malloc.os) > > > libc_pic.a(malloc.os) has an undefined __libc_message > > > __libc_message fetches libc_pic.a(libc_fatal.os) > > > > > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > > > >>> defined at dl-fxstatat64.c > > > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > > > >>> defined at libc_fatal.c > > > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > > > > > lld processes --defsym after all input files, so this trick does not > > > suppress multiple definition errors with lld. Split the step into two > > > and use an object file to make the intention more obvious and make lld > > > work. > > > > > > This is conceptually more appropriate because --defsym defines a SHN_ABS > > > symbol while a normal definition is relative to the image base. > > > > > > > This is irrelevant since --defsym was used to create a temporary file which was > > removed immediately after it was created: > > > > /usr/bin/gcc -nostdlib -nostartfiles -r -o > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 > > -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 > > -Wl,--defsym=__stack_chk_fail_local=0 \ > > '-Wl,-(' > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a > > -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > > > > > --- > > > elf/Makefile | 11 ++++------- > > > 1 file changed, 4 insertions(+), 7 deletions(-) > > > > > > diff --git a/elf/Makefile b/elf/Makefile > > > index 0b4d78c874..299bf24b49 100644 > > > --- a/elf/Makefile > > > +++ b/elf/Makefile > > > @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > > > malloc \ > > > realloc \ > > > > > > -# The GCC arguments that implement $(rtld-stubbed-symbols). > > > -rtld-stubbed-symbols-args = \ > > > - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > > > - > > > ifeq ($(have-ssp),yes) > > > # rtld is not built with the stack protector, so these references will > > > # go away in the rebuilds. > > > @@ -536,9 +532,10 @@ endif > > > > > > $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > > > @-rm -f $@T > > > - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > > > - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > > > - rm -f $@.o > > > + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > > > + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - > > > > Please generate > > > > .globl symbol; > > symbol = 0; > > > > to make it closer to -Wl,--defsym=symbol=0. > > If symbol: and symbol = 0; work, isn't symbol: slightly better because > it looks more normal? > Or is the intention here using SHN_ABS to make it clear these symbols > are special? Generate machine independent assembly codes is tricky. We should make before and after the change as close as possible to avoid ANY surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE to decide using ".set" vs "=".
On Tue, Jan 19, 2021 at 4:31 AM H.J. Lu <hjl.tools@gmail.com> wrote: > > On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: > > > > On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > > > > > On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha > > > <libc-alpha@sourceware.org> wrote: > > > > > > > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > > > > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > > > > fetched. This trick is used to avoid multiple definition errors which > > > > would happen as a chain result: > > > > > > > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > > > > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > > > > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > > > > free fetches libc_pic.a(malloc.os) > > > > libc_pic.a(malloc.os) has an undefined __libc_message > > > > __libc_message fetches libc_pic.a(libc_fatal.os) > > > > > > > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > > > > >>> defined at dl-fxstatat64.c > > > > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > > > > >>> defined at libc_fatal.c > > > > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > > > > > > > lld processes --defsym after all input files, so this trick does not > > > > suppress multiple definition errors with lld. Split the step into two > > > > and use an object file to make the intention more obvious and make lld > > > > work. > > > > > > > > This is conceptually more appropriate because --defsym defines a SHN_ABS > > > > symbol while a normal definition is relative to the image base. > > > > > > > > > > This is irrelevant since --defsym was used to create a temporary file which was > > > removed immediately after it was created: > > > > > > /usr/bin/gcc -nostdlib -nostartfiles -r -o > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > > -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 > > > -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 > > > -Wl,--defsym=__stack_chk_fail_local=0 \ > > > '-Wl,-(' > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a > > > -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > > rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > > mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > > > > > > > --- > > > > elf/Makefile | 11 ++++------- > > > > 1 file changed, 4 insertions(+), 7 deletions(-) > > > > > > > > diff --git a/elf/Makefile b/elf/Makefile > > > > index 0b4d78c874..299bf24b49 100644 > > > > --- a/elf/Makefile > > > > +++ b/elf/Makefile > > > > @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > > > > malloc \ > > > > realloc \ > > > > > > > > -# The GCC arguments that implement $(rtld-stubbed-symbols). > > > > -rtld-stubbed-symbols-args = \ > > > > - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > > > > - > > > > ifeq ($(have-ssp),yes) > > > > # rtld is not built with the stack protector, so these references will > > > > # go away in the rebuilds. > > > > @@ -536,9 +532,10 @@ endif > > > > > > > > $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > > > > @-rm -f $@T > > > > - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > > > > - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > > > > - rm -f $@.o > > > > + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > > > > + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - > > > > > > Please generate > > > > > > .globl symbol; > > > symbol = 0; > > > > > > to make it closer to -Wl,--defsym=symbol=0. > > > > If symbol: and symbol = 0; work, isn't symbol: slightly better because > > it looks more normal? > > Or is the intention here using SHN_ABS to make it clear these symbols > > are special? > > Generate machine independent assembly codes is tricky. We should > make before and after the change as close as possible to avoid ANY > surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE > to decide using ".set" vs "=". > > -- > H.J. Thanks for the tip. In this case I think the patch as is (sticking with `foo:`, don't use `foo = 0` or set) is better. foo: works everywhere.
On Wed, Jan 20, 2021 at 10:51 AM Fāng-ruì Sòng <maskray@google.com> wrote: > > On Tue, Jan 19, 2021 at 4:31 AM H.J. Lu <hjl.tools@gmail.com> wrote: > > > > On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: > > > > > > On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: > > > > > > > > On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha > > > > <libc-alpha@sourceware.org> wrote: > > > > > > > > > > The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > > > > > definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > > > > > fetched. This trick is used to avoid multiple definition errors which > > > > > would happen as a chain result: > > > > > > > > > > dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > > > > > __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > > > > > libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > > > > > free fetches libc_pic.a(malloc.os) > > > > > libc_pic.a(malloc.os) has an undefined __libc_message > > > > > __libc_message fetches libc_pic.a(libc_fatal.os) > > > > > > > > > > libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > > > > > >>> defined at dl-fxstatat64.c > > > > > >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > > > > > >>> defined at libc_fatal.c > > > > > >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > > > > > > > > > > lld processes --defsym after all input files, so this trick does not > > > > > suppress multiple definition errors with lld. Split the step into two > > > > > and use an object file to make the intention more obvious and make lld > > > > > work. > > > > > > > > > > This is conceptually more appropriate because --defsym defines a SHN_ABS > > > > > symbol while a normal definition is relative to the image base. > > > > > > > > > > > > > This is irrelevant since --defsym was used to create a temporary file which was > > > > removed immediately after it was created: > > > > > > > > /usr/bin/gcc -nostdlib -nostartfiles -r -o > > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > > > -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 > > > > -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 > > > > -Wl,--defsym=__stack_chk_fail_local=0 \ > > > > '-Wl,-(' > > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os > > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a > > > > -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > > > rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > > > > mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > > > > /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > > > > > > > > > --- > > > > > elf/Makefile | 11 ++++------- > > > > > 1 file changed, 4 insertions(+), 7 deletions(-) > > > > > > > > > > diff --git a/elf/Makefile b/elf/Makefile > > > > > index 0b4d78c874..299bf24b49 100644 > > > > > --- a/elf/Makefile > > > > > +++ b/elf/Makefile > > > > > @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > > > > > malloc \ > > > > > realloc \ > > > > > > > > > > -# The GCC arguments that implement $(rtld-stubbed-symbols). > > > > > -rtld-stubbed-symbols-args = \ > > > > > - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > > > > > - > > > > > ifeq ($(have-ssp),yes) > > > > > # rtld is not built with the stack protector, so these references will > > > > > # go away in the rebuilds. > > > > > @@ -536,9 +532,10 @@ endif > > > > > > > > > > $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > > > > > @-rm -f $@T > > > > > - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > > > > > - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > > > > > - rm -f $@.o > > > > > + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > > > > > + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - > > > > > > > > Please generate > > > > > > > > .globl symbol; > > > > symbol = 0; > > > > > > > > to make it closer to -Wl,--defsym=symbol=0. > > > > > > If symbol: and symbol = 0; work, isn't symbol: slightly better because > > > it looks more normal? > > > Or is the intention here using SHN_ABS to make it clear these symbols > > > are special? > > > > Generate machine independent assembly codes is tricky. We should > > make before and after the change as close as possible to avoid ANY > > surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE > > to decide using ".set" vs "=". > > > > -- > > H.J. > > Thanks for the tip. In this case I think the patch as is (sticking > with `foo:`, don't use `foo = 0` or set) is better. > foo: works everywhere. Ping. I think the patch as-is is better than the alternative approach using either `=` or `.set`.
On 27/01/2021 22:03, Fāng-ruì Sòng via Libc-alpha wrote: > On Wed, Jan 20, 2021 at 10:51 AM Fāng-ruì Sòng <maskray@google.com> wrote: >> >> On Tue, Jan 19, 2021 at 4:31 AM H.J. Lu <hjl.tools@gmail.com> wrote: >>> >>> On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: >>>> >>>> On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: >>>>> >>>>> On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha >>>>> <libc-alpha@sourceware.org> wrote: >>>>>> >>>>>> The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os >>>>>> definitions before libc_pic.a so that libc_pic.a(malloc.os) is not >>>>>> fetched. This trick is used to avoid multiple definition errors which >>>>>> would happen as a chain result: >>>>>> >>>>>> dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size >>>>>> __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) >>>>>> libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free >>>>>> free fetches libc_pic.a(malloc.os) >>>>>> libc_pic.a(malloc.os) has an undefined __libc_message >>>>>> __libc_message fetches libc_pic.a(libc_fatal.os) >>>>>> >>>>>> libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) >>>>>> >>> defined at dl-fxstatat64.c >>>>>> >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) >>>>>> >>> defined at libc_fatal.c >>>>>> >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a >>>>>> >>>>>> lld processes --defsym after all input files, so this trick does not >>>>>> suppress multiple definition errors with lld. Split the step into two >>>>>> and use an object file to make the intention more obvious and make lld >>>>>> work. >>>>>> >>>>>> This is conceptually more appropriate because --defsym defines a SHN_ABS >>>>>> symbol while a normal definition is relative to the image base. >>>>>> >>>>> >>>>> This is irrelevant since --defsym was used to create a temporary file which was >>>>> removed immediately after it was created: >>>>> >>>>> /usr/bin/gcc -nostdlib -nostartfiles -r -o >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o >>>>> -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 >>>>> -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 >>>>> -Wl,--defsym=__stack_chk_fail_local=0 \ >>>>> '-Wl,-(' >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a >>>>> -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT >>>>> rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o >>>>> mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map >>>>> >>>>>> --- >>>>>> elf/Makefile | 11 ++++------- >>>>>> 1 file changed, 4 insertions(+), 7 deletions(-) >>>>>> >>>>>> diff --git a/elf/Makefile b/elf/Makefile >>>>>> index 0b4d78c874..299bf24b49 100644 >>>>>> --- a/elf/Makefile >>>>>> +++ b/elf/Makefile >>>>>> @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ >>>>>> malloc \ >>>>>> realloc \ >>>>>> >>>>>> -# The GCC arguments that implement $(rtld-stubbed-symbols). >>>>>> -rtld-stubbed-symbols-args = \ >>>>>> - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) >>>>>> - >>>>>> ifeq ($(have-ssp),yes) >>>>>> # rtld is not built with the stack protector, so these references will >>>>>> # go away in the rebuilds. >>>>>> @@ -536,9 +532,10 @@ endif >>>>>> >>>>>> $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a >>>>>> @-rm -f $@T >>>>>> - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ >>>>>> - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T >>>>>> - rm -f $@.o >>>>>> + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ >>>>>> + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - >>>>> >>>>> Please generate >>>>> >>>>> .globl symbol; >>>>> symbol = 0; >>>>> >>>>> to make it closer to -Wl,--defsym=symbol=0. >>>> >>>> If symbol: and symbol = 0; work, isn't symbol: slightly better because >>>> it looks more normal? >>>> Or is the intention here using SHN_ABS to make it clear these symbols >>>> are special? >>> >>> Generate machine independent assembly codes is tricky. We should >>> make before and after the change as close as possible to avoid ANY >>> surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE >>> to decide using ".set" vs "=". >>> >>> -- >>> H.J. >> >> Thanks for the tip. In this case I think the patch as is (sticking >> with `foo:`, don't use `foo = 0` or set) is better. >> foo: works everywhere. > > Ping. I think the patch as-is is better than the alternative approach > using either `=` or `.set`. The patch breaks both arc-linux-gnuhf and hppa-linux-gnu with recent ld.bfd 2.26, as below. We will need to sort these out. arc-linux-gnuhf: make[2]: Entering directory '/home/azanella/glibc/glibc-git/elf' echo '.globl calloc; .globl free; .globl malloc; .globl realloc; .globl __stack_chk_fail; .globl __stack_chk_fail_local; calloc: free: malloc: realloc: __stack_chk_fail: __stack_chk_fail_local:' | \ /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/bin/arc-glibc-linux-gnuhf-gcc -o /home/azanella/glibc/build/arc-linux-gnuhf/elf/librtld.mapT.o -g -Werror=undef -Wa,--noexecstack -c -x assembler - /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/bin/arc-glibc-linux-gnuhf-gcc -nostdlib -nostartfiles -r -o /home/azanella/glibc/build/arc-linux-gnuhf/elf/librtld.map.o /home/azanella/glibc/build/arc-linux-gnuhf/elf/librtld.mapT.o '-Wl,-(' /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a -lgcc '-Wl,-)' -Wl,-Map,/home/azanella/glibc/build/arc-linux-gnuhf/elf/librtld.mapT /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(sbrk.os): in function `__GI___sbrk': /home/azanella/glibc/glibc-git/misc/sbrk.c:37: multiple definition of `__sbrk'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/../misc/sbrk.c:37: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(libc_fatal.os): in function `__GI___libc_fatal': /home/azanella/glibc/glibc-git/libio/../sysdeps/posix/libc_fatal.c:161: multiple definition of `__GI___libc_fatal'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:267: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(libc_fatal.os): in function `__GI___libc_fatal': /home/azanella/glibc/glibc-git/libio/../sysdeps/posix/libc_fatal.c:161: multiple definition of `__libc_fatal'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:267: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(_itoa.os): in function `_itoa': /home/azanella/glibc/glibc-git/stdio-common/_itoa.c:196: multiple definition of `_itoa'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:323: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(getcwd.os): in function `__GI___getcwd': /home/azanella/glibc/glibc-git/io/../sysdeps/unix/sysv/linux/getcwd.c:50: multiple definition of `__getcwd'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/../sysdeps/unix/sysv/linux/getcwd.c:50: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(dl-error.os): in function `__GI__dl_signal_exception': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:91: multiple definition of `_dl_signal_exception'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:91: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(dl-error.os): in function `__GI__dl_signal_error': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:109: multiple definition of `_dl_signal_error'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:109: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(dl-error.os): in function `__GI__dl_catch_exception': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:175: multiple definition of `_dl_catch_exception'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:175: first defined here /home/azanella/toolchain/install/compilers/arc-linux-gnuhf/lib/gcc/arc-glibc-linux-gnuhf/10.2.1/../../../../arc-glibc-linux-gnuhf/bin/ld: /home/azanella/glibc/build/arc-linux-gnuhf/libc_pic.a(dl-error.os): in function `__GI__dl_catch_error': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:225: multiple definition of `_dl_catch_error'; /home/azanella/glibc/build/arc-linux-gnuhf/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:225: first defined here collect2: error: ld returned 1 exit status make[2]: *** [Makefile:538: /home/azanella/glibc/build/arc-linux-gnuhf/elf/librtld.map] Error 1 hppa-linux-gnu: echo '.globl calloc; .globl free; .globl malloc; .globl realloc; calloc: free: malloc: realloc:' | \ /home/azanella/toolchain/install/compilers/hppa-linux-gnu/bin/hppa-glibc-linux-gnu-gcc -o /home/azanella/glibc/build/hppa-linux-gnu/elf/librtld.mapT.o -g -Werror=undef -c -x assembler - /home/azanella/toolchain/install/compilers/hppa-linux-gnu/bin/hppa-glibc-linux-gnu-gcc -nostdlib -nostartfiles -r -o /home/azanella/glibc/build/hppa-linux-gnu/elf/librtld.map.o /home/azanella/glibc/build/hppa-linux-gnu/elf/librtld.mapT.o '-Wl,-(' /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a -lgcc '-Wl,-)' -Wl,-Map,/home/azanella/glibc/build/hppa-linux-gnu/elf/librtld.mapT /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(sbrk.os): in function `__GI___sbrk': /home/azanella/glibc/glibc-git/misc/sbrk.c:37: multiple definition of `__sbrk'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/../misc/sbrk.c:37: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(libc_fatal.os): in function `__GI___libc_fatal': /home/azanella/glibc/glibc-git/libio/../sysdeps/posix/libc_fatal.c:161: multiple definition of `__GI___libc_fatal'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:268: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(libc_fatal.os): in function `__GI___libc_fatal': /home/azanella/glibc/glibc-git/libio/../sysdeps/posix/libc_fatal.c:161: multiple definition of `__libc_fatal'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:268: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(_itoa.os): in function `_itoa': /home/azanella/glibc/glibc-git/stdio-common/_itoa.c:196: multiple definition of `_itoa'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-minimal.c:323: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(getcwd.os): in function `__GI___getcwd': /home/azanella/glibc/glibc-git/io/../sysdeps/unix/sysv/linux/getcwd.c:50: multiple definition of `__getcwd'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/../sysdeps/unix/sysv/linux/getcwd.c:50: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(dl-error.os): in function `__GI__dl_signal_exception': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:91: multiple definition of `_dl_signal_exception'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:91: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(dl-error.os): in function `__GI__dl_signal_error': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:109: multiple definition of `_dl_signal_error'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:109: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(dl-error.os): in function `__GI__dl_catch_exception': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:175: multiple definition of `_dl_catch_exception'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:175: first defined here /home/azanella/toolchain/install/compilers/hppa-linux-gnu/lib/gcc/hppa-glibc-linux-gnu/10.2.1/../../../../hppa-glibc-linux-gnu/bin/ld: /home/azanella/glibc/build/hppa-linux-gnu/libc_pic.a(dl-error.os): in function `__GI__dl_catch_error': /home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:225: multiple definition of `_dl_catch_error'; /home/azanella/glibc/build/hppa-linux-gnu/elf/dl-allobjs.os:/home/azanella/glibc/glibc-git/elf/dl-error-skeleton.c:225: first defined here collect2: error: ld returned 1 exit status
On Fri, Jan 29, 2021 at 7:26 AM Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org> wrote: > > > > On 27/01/2021 22:03, Fāng-ruì Sòng via Libc-alpha wrote: > > On Wed, Jan 20, 2021 at 10:51 AM Fāng-ruì Sòng <maskray@google.com> wrote: > >> > >> On Tue, Jan 19, 2021 at 4:31 AM H.J. Lu <hjl.tools@gmail.com> wrote: > >>> > >>> On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: > >>>> > >>>> On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: > >>>>> > >>>>> On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha > >>>>> <libc-alpha@sourceware.org> wrote: > >>>>>> > >>>>>> The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os > >>>>>> definitions before libc_pic.a so that libc_pic.a(malloc.os) is not > >>>>>> fetched. This trick is used to avoid multiple definition errors which > >>>>>> would happen as a chain result: > >>>>>> > >>>>>> dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size > >>>>>> __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) > >>>>>> libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free > >>>>>> free fetches libc_pic.a(malloc.os) > >>>>>> libc_pic.a(malloc.os) has an undefined __libc_message > >>>>>> __libc_message fetches libc_pic.a(libc_fatal.os) > >>>>>> > >>>>>> libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) > >>>>>> >>> defined at dl-fxstatat64.c > >>>>>> >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) > >>>>>> >>> defined at libc_fatal.c > >>>>>> >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a > >>>>>> > >>>>>> lld processes --defsym after all input files, so this trick does not > >>>>>> suppress multiple definition errors with lld. Split the step into two > >>>>>> and use an object file to make the intention more obvious and make lld > >>>>>> work. > >>>>>> > >>>>>> This is conceptually more appropriate because --defsym defines a SHN_ABS > >>>>>> symbol while a normal definition is relative to the image base. > >>>>>> > >>>>> > >>>>> This is irrelevant since --defsym was used to create a temporary file which was > >>>>> removed immediately after it was created: > >>>>> > >>>>> /usr/bin/gcc -nostdlib -nostartfiles -r -o > >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > >>>>> -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 > >>>>> -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 > >>>>> -Wl,--defsym=__stack_chk_fail_local=0 \ > >>>>> '-Wl,-(' > >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os > >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a > >>>>> -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > >>>>> rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o > >>>>> mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT > >>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map > >>>>> > >>>>>> --- > >>>>>> elf/Makefile | 11 ++++------- > >>>>>> 1 file changed, 4 insertions(+), 7 deletions(-) > >>>>>> > >>>>>> diff --git a/elf/Makefile b/elf/Makefile > >>>>>> index 0b4d78c874..299bf24b49 100644 > >>>>>> --- a/elf/Makefile > >>>>>> +++ b/elf/Makefile > >>>>>> @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ > >>>>>> malloc \ > >>>>>> realloc \ > >>>>>> > >>>>>> -# The GCC arguments that implement $(rtld-stubbed-symbols). > >>>>>> -rtld-stubbed-symbols-args = \ > >>>>>> - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) > >>>>>> - > >>>>>> ifeq ($(have-ssp),yes) > >>>>>> # rtld is not built with the stack protector, so these references will > >>>>>> # go away in the rebuilds. > >>>>>> @@ -536,9 +532,10 @@ endif > >>>>>> > >>>>>> $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a > >>>>>> @-rm -f $@T > >>>>>> - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ > >>>>>> - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T > >>>>>> - rm -f $@.o > >>>>>> + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ > >>>>>> + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - > >>>>> > >>>>> Please generate > >>>>> > >>>>> .globl symbol; > >>>>> symbol = 0; > >>>>> > >>>>> to make it closer to -Wl,--defsym=symbol=0. > >>>> > >>>> If symbol: and symbol = 0; work, isn't symbol: slightly better because > >>>> it looks more normal? > >>>> Or is the intention here using SHN_ABS to make it clear these symbols > >>>> are special? > >>> > >>> Generate machine independent assembly codes is tricky. We should > >>> make before and after the change as close as possible to avoid ANY > >>> surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE > >>> to decide using ".set" vs "=". > >>> > >>> -- > >>> H.J. > >> > >> Thanks for the tip. In this case I think the patch as is (sticking > >> with `foo:`, don't use `foo = 0` or set) is better. > >> foo: works everywhere. > > > > Ping. I think the patch as-is is better than the alternative approach > > using either `=` or `.set`. > > The patch breaks both arc-linux-gnuhf and hppa-linux-gnu with recent > ld.bfd 2.26, as below. > > We will need to sort these out. > Does my suggestion work?
On 29/01/2021 12:29, H.J. Lu wrote: > On Fri, Jan 29, 2021 at 7:26 AM Adhemerval Zanella via Libc-alpha > <libc-alpha@sourceware.org> wrote: >> >> >> >> On 27/01/2021 22:03, Fāng-ruì Sòng via Libc-alpha wrote: >>> On Wed, Jan 20, 2021 at 10:51 AM Fāng-ruì Sòng <maskray@google.com> wrote: >>>> >>>> On Tue, Jan 19, 2021 at 4:31 AM H.J. Lu <hjl.tools@gmail.com> wrote: >>>>> >>>>> On Tue, Jan 19, 2021 at 12:50 AM Fāng-ruì Sòng <maskray@google.com> wrote: >>>>>> >>>>>> On Mon, Jan 18, 2021 at 4:04 PM H.J. Lu <hjl.tools@gmail.com> wrote: >>>>>>> >>>>>>> On Mon, Dec 28, 2020 at 11:50 AM Fangrui Song via Libc-alpha >>>>>>> <libc-alpha@sourceware.org> wrote: >>>>>>>> >>>>>>>> The existing code specifies -Wl,--defsym=malloc=0 and other malloc.os >>>>>>>> definitions before libc_pic.a so that libc_pic.a(malloc.os) is not >>>>>>>> fetched. This trick is used to avoid multiple definition errors which >>>>>>>> would happen as a chain result: >>>>>>>> >>>>>>>> dl-allobjs.os has an undefined __libc_scratch_buffer_set_array_size >>>>>>>> __libc_scratch_buffer_set_array_size fetches libc_pic.a(scratch_buffer_set_array_size.os) >>>>>>>> libc_pic.a(scratch_buffer_set_array_size.os) has an undefined free >>>>>>>> free fetches libc_pic.a(malloc.os) >>>>>>>> libc_pic.a(malloc.os) has an undefined __libc_message >>>>>>>> __libc_message fetches libc_pic.a(libc_fatal.os) >>>>>>>> >>>>>>>> libc_fatal.os will cause a multiple definition error (__GI___libc_fatal) >>>>>>>> >>> defined at dl-fxstatat64.c >>>>>>>> >>> /tmp/p/glibc/Release/elf/dl-allobjs.os:(__GI___libc_fatal) >>>>>>>> >>> defined at libc_fatal.c >>>>>>>> >>> libc_fatal.os:(.text+0x240) in archive /tmp/p/glibc/Release/libc_pic.a >>>>>>>> >>>>>>>> lld processes --defsym after all input files, so this trick does not >>>>>>>> suppress multiple definition errors with lld. Split the step into two >>>>>>>> and use an object file to make the intention more obvious and make lld >>>>>>>> work. >>>>>>>> >>>>>>>> This is conceptually more appropriate because --defsym defines a SHN_ABS >>>>>>>> symbol while a normal definition is relative to the image base. >>>>>>>> >>>>>>> >>>>>>> This is irrelevant since --defsym was used to create a temporary file which was >>>>>>> removed immediately after it was created: >>>>>>> >>>>>>> /usr/bin/gcc -nostdlib -nostartfiles -r -o >>>>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o >>>>>>> -Wl,--defsym=calloc=0 -Wl,--defsym=free=0 -Wl,--defsym=malloc=0 >>>>>>> -Wl,--defsym=realloc=0 -Wl,--defsym=__stack_chk_fail=0 >>>>>>> -Wl,--defsym=__stack_chk_fail_local=0 \ >>>>>>> '-Wl,-(' >>>>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/dl-allobjs.os >>>>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/libc_pic.a >>>>>>> -lgcc '-Wl,-)' -Wl,-Map,/export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT >>>>>>> rm -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map.o >>>>>>> mv -f /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.mapT >>>>>>> /export/users/hjl/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/elf/librtld.map >>>>>>> >>>>>>>> --- >>>>>>>> elf/Makefile | 11 ++++------- >>>>>>>> 1 file changed, 4 insertions(+), 7 deletions(-) >>>>>>>> >>>>>>>> diff --git a/elf/Makefile b/elf/Makefile >>>>>>>> index 0b4d78c874..299bf24b49 100644 >>>>>>>> --- a/elf/Makefile >>>>>>>> +++ b/elf/Makefile >>>>>>>> @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ >>>>>>>> malloc \ >>>>>>>> realloc \ >>>>>>>> >>>>>>>> -# The GCC arguments that implement $(rtld-stubbed-symbols). >>>>>>>> -rtld-stubbed-symbols-args = \ >>>>>>>> - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) >>>>>>>> - >>>>>>>> ifeq ($(have-ssp),yes) >>>>>>>> # rtld is not built with the stack protector, so these references will >>>>>>>> # go away in the rebuilds. >>>>>>>> @@ -536,9 +532,10 @@ endif >>>>>>>> >>>>>>>> $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a >>>>>>>> @-rm -f $@T >>>>>>>> - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ >>>>>>>> - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T >>>>>>>> - rm -f $@.o >>>>>>>> + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ >>>>>>>> + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - >>>>>>> >>>>>>> Please generate >>>>>>> >>>>>>> .globl symbol; >>>>>>> symbol = 0; >>>>>>> >>>>>>> to make it closer to -Wl,--defsym=symbol=0. >>>>>> >>>>>> If symbol: and symbol = 0; work, isn't symbol: slightly better because >>>>>> it looks more normal? >>>>>> Or is the intention here using SHN_ABS to make it clear these symbols >>>>>> are special? >>>>> >>>>> Generate machine independent assembly codes is tricky. We should >>>>> make before and after the change as close as possible to avoid ANY >>>>> surprises. BTW, you need to check HAVE_ASM_SET_DIRECTIVE >>>>> to decide using ".set" vs "=". >>>>> >>>>> -- >>>>> H.J. >>>> >>>> Thanks for the tip. In this case I think the patch as is (sticking >>>> with `foo:`, don't use `foo = 0` or set) is better. >>>> foo: works everywhere. >>> >>> Ping. I think the patch as-is is better than the alternative approach >>> using either `=` or `.set`. >> >> The patch breaks both arc-linux-gnuhf and hppa-linux-gnu with recent >> ld.bfd 2.26, as below. >> >> We will need to sort these out. The issue was in fact that hppa and arc uses no default asm line separators (represented by ASM_LINE_SEP within code): hppa uses '!' while arc '`'. By replacing echo with printf and issuing a new line explicit I see that all targets build: --- diff --git a/elf/Makefile b/elf/Makefile index 5d666b1b0c..e5c04f682c 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -526,10 +526,6 @@ rtld-stubbed-symbols = \ malloc \ realloc \ -# The GCC arguments that implement $(rtld-stubbed-symbols). -rtld-stubbed-symbols-args = \ - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) - ifeq ($(have-ssp),yes) # rtld is not built with the stack protector, so these references will # go away in the rebuilds. @@ -538,9 +534,10 @@ endif $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a @-rm -f $@T - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T - rm -f $@.o + printf '$(patsubst %,.globl %;\n,$(rtld-stubbed-symbols)) $(patsubst %,% = 0;\n,$(rtld-stubbed-symbols))' | \ + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - + $(reloc-link) -o $@.o $@T.o '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T + rm -f %@T.o $@.o mv -f $@T $@ # For lld, skip preceding addresses and values before matching the archive and the member.
diff --git a/elf/Makefile b/elf/Makefile index 0b4d78c874..299bf24b49 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -524,10 +524,6 @@ rtld-stubbed-symbols = \ malloc \ realloc \ -# The GCC arguments that implement $(rtld-stubbed-symbols). -rtld-stubbed-symbols-args = \ - $(patsubst %,-Wl$(comma)--defsym=%=0, $(rtld-stubbed-symbols)) - ifeq ($(have-ssp),yes) # rtld is not built with the stack protector, so these references will # go away in the rebuilds. @@ -536,9 +532,10 @@ endif $(objpfx)librtld.map: $(objpfx)dl-allobjs.os $(common-objpfx)libc_pic.a @-rm -f $@T - $(reloc-link) -o $@.o $(rtld-stubbed-symbols-args) \ - '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T - rm -f $@.o + echo '$(patsubst %,.globl %;,$(rtld-stubbed-symbols)) $(patsubst %,%:,$(rtld-stubbed-symbols))' | \ + $(CC) -o $@T.o $(ASFLAGS) -c -x assembler - + $(reloc-link) -o $@.o $@T.o '-Wl,-(' $^ -lgcc '-Wl,-)' -Wl,-Map,$@T + rm -f %@T.o $@.o mv -f $@T $@ # For lld, skip preceding addresses and values before matching the archive and the member.