Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752283Ab0HXFX5 (ORCPT ); Tue, 24 Aug 2010 01:23:57 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:41953 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751357Ab0HXFXy (ORCPT ); Tue, 24 Aug 2010 01:23:54 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=w6rAxlCSamq0l8miRnKilL36ixf/V5+eWJVcsm3ZfOxZ0YroS6XucLG/7JC6bEoKda h97/AC7rQyU05O71cBSjPhKnV0e3QJnUxd6xN9EX5vI1hQY2AZ59UCif7b69QlNLQhfZ WUEN0MsaHNPh+v2tNj1irHOV6adiuTtH5rX20= Subject: Re: [PATCH] perf tools: Fix linking errors with --as-needed flag From: Tom Zanussi To: "Kirill A. Shutemov" Cc: Arnaldo Carvalho de Melo , Ozan =?UTF-8?Q?=C3=87a=C4=9Flayan?= , linux-kernel@vger.kernel.org, mingo@elte.hu In-Reply-To: <20100823165319.GA19611@shutemov.name> References: <1279449937-29115-1-git-send-email-ozan@pardus.org.tr> <4C42DFC0.1090708@pardus.org.tr> <20100821172433.GF2973@ghostprotocols.net> <1282459432.11398.53.camel@tropicana> <1282531453.30047.8.camel@tropicana> <20100823165319.GA19611@shutemov.name> Content-Type: text/plain; charset="UTF-8" Date: Tue, 24 Aug 2010 00:23:50 -0500 Message-ID: <1282627430.28324.8.camel@tropicana> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9864 Lines: 231 On Mon, 2010-08-23 at 19:53 +0300, Kirill A. Shutemov wrote: > On Sun, Aug 22, 2010 at 09:44:13PM -0500, Tom Zanussi wrote: > > On Sun, 2010-08-22 at 01:43 -0500, Tom Zanussi wrote: > > > Hi, > > > > > > On Sat, 2010-08-21 at 14:24 -0300, Arnaldo Carvalho de Melo wrote: > > > > Em Sun, Jul 18, 2010 at 02:04:32PM +0300, Ozan Çağlayan escreveu: > > > > > On 18.07.2010 13:45, Ozan Çağlayan wrote: > > > > > > External shared libraries should never be appended to the LDFLAGS as > > > > > > this messes the linking order. As EXTLIBS collects those libraries, > > > > > > it seems that perl and python libraries should also be appended > > > > > > to EXTLIBS. > > > > > > > > > > > > Also fix the broken linking order. > > > > > > > > > > Hm actually the PERL_EMBED_LDOPTS may contain LDFLAGS and LIBADD according > > > > > to distribution's perl package configuration's goodness/badness. On my system > > > > > the return value is crap which bloats the linking process: > > > > > > > > > > -rdynamic -Wl,-rpath,/usr/lib/perl5/5.10.1/i686-linux-thread-multi/CORE -fstack-protector -L/usr/local/lib -L/usr/lib/perl5/5.10.1/i686-linux-thread-multi/CORE -lperl -lpthread -lnsl -ldl -lm -lcrypt -lutil -lc > > > > > > > > > > PYTHON_EMBED_LDOPTS evaluates python-config --ldflags and adds these to > > > > > ALL_LDFLAGS. (--libs and --ldflags are synonyms for python-config). According > > > > > to python-config this code *never* returns LDFLAGS so it's safe to put them in > > > > > EXTLIBS. > > > > > > > > > > So the cure may be more than this patch for perl stuff, but at least it fixes my > > > > > linking problems with -Wl, --as-needed. > > > > > > > > Can you refresh this patch? I had it in the back of my mind, remembered > > > > it when considering a similar patch by Kirill, but his covers just the > > > > python case. > > > > > > > > Tom, can you please check Ozan's and Kirill's patches and tell me if I > > > > can stick your Acked-by to them? > > > > > > > > > > I refreshed Ozan's patch against tip and tried both with and without > > > -Wl,--as-needed and it worked fine for both Perl and Python, on my > > > Ubuntu 9.10 system. The refreshed patch I used is included below. > > > > > > It wasn't clear to me whether Ozan's PERL_EMBED_LDOPTS output still > > > caused link errors; here's mine, which didn't: > > > > > > trz@tropicana:~$ perl -MExtUtils::Embed -e ldopts > > > -Wl,-E -L/usr/local/lib -L/usr/lib/perl/5.10/CORE -lperl -ldl -lm > > > -lpthread -lc -lcrypt > > > > > > In any case, since neither ExtUtils::Embed nor python-config seem to > > > have a way to get the LDFLAGS and LIBADD components separately, we'll > > > have to find some other way to do that if necessary. > > > > > > > Looking into it a bit further, both ExtUtils::Embed -e ldopts and > > python-config --ldflags put the libs at the end, so we should be able to > > parse the output of those and take only the parts we need for each > > component. How about something like this instead? > > > > Tom > > > > --- > > > > [PATCH] Refresh of Ozan Çağlayan's patch: perf tools: Fix linking errors > > with --as-needed flag: > > > > External shared libraries should never be appended to the LDFLAGS as > > this messes the linking order. As EXTLIBS collects those libraries, > > it seems that perl and python libraries should also be appended > > to EXTLIBS. > > > > Also fix the broken linking order. > > > > v2: add commands to separate out LDFLAGS and libs from both Perl and > > Python LDOPTS (Tom Zanussi) > > > > Signed-off-by: Tom Zanussi > > Tested-by: Kirill A. Shutemov > > But, probably better to do it with make: > > diff --git a/tools/perf/Makefile b/tools/perf/Makefile > index 4f1fa77..03a53a9 100644 > --- a/tools/perf/Makefile > +++ b/tools/perf/Makefile > @@ -313,6 +313,9 @@ TEST_PROGRAMS = > > SCRIPT_SH += perf-archive.sh > > +grep-libs = $(filter -l%,$(1)) > +strip-libs = $(filter-out -l%,$(1)) > + > # > # No Perl scripts right now: > # > @@ -588,14 +591,17 @@ endif > ifdef NO_LIBPERL > BASIC_CFLAGS += -DNO_LIBPERL > else > - PERL_EMBED_LDOPTS = `perl -MExtUtils::Embed -e ldopts 2>/dev/null` > + PERL_EMBED_LDOPTS = $(shell perl -MExtUtils::Embed -e ldopts 2>/dev/null) > + PERL_EMBED_LDFLAGS = $(call strip-libs,$(PERL_EMBED_LDOPTS)) > + PERL_EMBED_LIBADD = $(call grep-libs,$(PERL_EMBED_LDOPTS)) > PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null` > FLAGS_PERL_EMBED=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS) > > ifneq ($(call try-cc,$(SOURCE_PERL_EMBED),$(FLAGS_PERL_EMBED)),y) > BASIC_CFLAGS += -DNO_LIBPERL > else > - ALL_LDFLAGS += $(PERL_EMBED_LDOPTS) > + ALL_LDFLAGS += $(PERL_EMBED_LDFLAGS) > + EXTLIBS += $(PERL_EMBED_LIBADD) > LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-perl.o > LIB_OBJS += $(OUTPUT)scripts/perl/Perf-Trace-Util/Context.o > endif > @@ -604,13 +610,16 @@ endif > ifdef NO_LIBPYTHON > BASIC_CFLAGS += -DNO_LIBPYTHON > else > - PYTHON_EMBED_LDOPTS = `python-config --ldflags 2>/dev/null` > + PYTHON_EMBED_LDOPTS = $(shell python-config --ldflags 2>/dev/null) > + PYTHON_EMBED_LDFLAGS = $(call strip-libs,$(PYTHON_EMBED_LDOPTS)) > + PYTHON_EMBED_LIBADD = $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) > PYTHON_EMBED_CCOPTS = `python-config --cflags 2>/dev/null` > FLAGS_PYTHON_EMBED=$(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS) > ifneq ($(call try-cc,$(SOURCE_PYTHON_EMBED),$(FLAGS_PYTHON_EMBED)),y) > BASIC_CFLAGS += -DNO_LIBPYTHON > else > - ALL_LDFLAGS += $(PYTHON_EMBED_LDOPTS) > + ALL_LDFLAGS += $(PYTHON_EMBED_LDFLAGS) > + EXTLIBS += $(PYTHON_EMBED_LIBADD) > LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-python.o > LIB_OBJS += $(OUTPUT)scripts/python/Perf-Trace-Util/Context.o > endif > @@ -910,8 +919,8 @@ $(OUTPUT)perf.o: perf.c $(OUTPUT)common-cmds.h $(OUTPUT)PERF-CFLAGS > $(ALL_CFLAGS) -c $(filter %.c,$^) -o $@ > > $(OUTPUT)perf$X: $(OUTPUT)perf.o $(BUILTIN_OBJS) $(PERFLIBS) > - $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(OUTPUT)perf.o \ > - $(BUILTIN_OBJS) $(ALL_LDFLAGS) $(LIBS) > + $(QUIET_LINK)$(CC) $(ALL_CFLAGS) $(ALL_LDFLAGS) $(OUTPUT)perf.o \ > + $(BUILTIN_OBJS) $(LIBS) -o $@ > > $(OUTPUT)builtin-help.o: builtin-help.c $(OUTPUT)common-cmds.h $(OUTPUT)PERF-CFLAGS > $(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) \ Yes, much better, thanks! Tested-by: Tom Zanussi BTW, I had some problems applying that patch, had to use -l and fix up a missing tab: --- tools/perf/Makefile | 21 +++++++++++++++------ 1 files changed, 15 insertions(+), 6 deletions(-) diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 26a3f2e..fe1e307 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -313,6 +313,9 @@ TEST_PROGRAMS = SCRIPT_SH += perf-archive.sh +grep-libs = $(filter -l%,$(1)) +strip-libs = $(filter-out -l%,$(1)) + # # No Perl scripts right now: # @@ -588,14 +591,17 @@ endif ifdef NO_LIBPERL BASIC_CFLAGS += -DNO_LIBPERL else - PERL_EMBED_LDOPTS = `perl -MExtUtils::Embed -e ldopts 2>/dev/null` + PERL_EMBED_LDOPTS = $(shell perl -MExtUtils::Embed -e ldopts 2>/dev/null) + PERL_EMBED_LDFLAGS = $(call strip-libs,$(PERL_EMBED_LDOPTS)) + PERL_EMBED_LIBADD = $(call grep-libs,$(PERL_EMBED_LDOPTS)) PERL_EMBED_CCOPTS = `perl -MExtUtils::Embed -e ccopts 2>/dev/null` FLAGS_PERL_EMBED=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS) ifneq ($(call try-cc,$(SOURCE_PERL_EMBED),$(FLAGS_PERL_EMBED)),y) BASIC_CFLAGS += -DNO_LIBPERL else - ALL_LDFLAGS += $(PERL_EMBED_LDOPTS) + ALL_LDFLAGS += $(PERL_EMBED_LDFLAGS) + EXTLIBS += $(PERL_EMBED_LIBADD) LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-perl.o LIB_OBJS += $(OUTPUT)scripts/perl/Perf-Trace-Util/Context.o endif @@ -604,13 +610,16 @@ endif ifdef NO_LIBPYTHON BASIC_CFLAGS += -DNO_LIBPYTHON else - PYTHON_EMBED_LDOPTS = `python-config --ldflags 2>/dev/null` + PYTHON_EMBED_LDOPTS = $(shell python-config --ldflags 2>/dev/null) + PYTHON_EMBED_LDFLAGS = $(call strip-libs,$(PYTHON_EMBED_LDOPTS)) + PYTHON_EMBED_LIBADD = $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) PYTHON_EMBED_CCOPTS = `python-config --cflags 2>/dev/null` FLAGS_PYTHON_EMBED=$(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS) ifneq ($(call try-cc,$(SOURCE_PYTHON_EMBED),$(FLAGS_PYTHON_EMBED)),y) BASIC_CFLAGS += -DNO_LIBPYTHON else - ALL_LDFLAGS += $(PYTHON_EMBED_LDOPTS) + ALL_LDFLAGS += $(PYTHON_EMBED_LDFLAGS) + EXTLIBS += $(PYTHON_EMBED_LIBADD) LIB_OBJS += $(OUTPUT)util/scripting-engines/trace-event-python.o LIB_OBJS += $(OUTPUT)scripts/python/Perf-Trace-Util/Context.o endif @@ -919,8 +928,8 @@ $(OUTPUT)perf.o: perf.c $(OUTPUT)common-cmds.h $(OUTPUT)PERF-CFLAGS $(ALL_CFLAGS) -c $(filter %.c,$^) -o $@ $(OUTPUT)perf$X: $(OUTPUT)perf.o $(BUILTIN_OBJS) $(PERFLIBS) - $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(OUTPUT)perf.o \ - $(BUILTIN_OBJS) $(ALL_LDFLAGS) $(LIBS) + $(QUIET_LINK)$(CC) $(ALL_CFLAGS) $(ALL_LDFLAGS) $(OUTPUT)perf.o \ + $(BUILTIN_OBJS) $(LIBS) -o $@ $(OUTPUT)builtin-help.o: builtin-help.c $(OUTPUT)common-cmds.h $(OUTPUT)PERF-CFLAGS $(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) \ -- 1.6.4.GIT -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/