On Mon, Mar 30, 2015 at 10:38 PM, Jakub Jelinek <ja...@redhat.com> wrote: > On Mon, Mar 30, 2015 at 07:08:00PM -0700, H.J. Lu wrote: >> --- a/gcc/gcc.c >> +++ b/gcc/gcc.c >> @@ -1566,11 +1566,13 @@ init_spec (void) >> if (in_sep && *p == '-' && strncmp (p, "-lgcc", 5) == 0) >> { >> init_gcc_specs (&obstack, >> + "-lgcc_nonshared " >> "-lgcc_s" >> #ifdef USE_LIBUNWIND_EXCEPTIONS >> " -lunwind" >> #endif >> , >> + "-lgcc_nonshared " >> "-lgcc", >> "-lgcc_eh" >> #ifdef USE_LIBUNWIND_EXCEPTIONS >> @@ -1591,7 +1593,9 @@ init_spec (void) >> /* Ug. We don't know shared library extensions. Hope that >> systems that use this form don't do shared libraries. */ >> init_gcc_specs (&obstack, >> + "libgcc_nonshared.a%s " >> "-lgcc_s", >> + "libgcc_nonshared.a%s " >> "libgcc.a%s", >> "libgcc_eh.a%s" > > Why do you need to link libgcc_nonshared.a twice here? -lgcc_s surely won't > add any new __cpu* undefined references.
The one added for -lgcc_s is for building shared C++ library since -lgcc isn't used and only -lgcc_s is used. The one added for -lgcc is for static linking since -lgcc_s isn't used. I updated the patch to add some testcases for -static. I couldn't find a way to add tests for: export/build/gnu/gcc/build-x86_64-linux/gcc/xg++ -B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O2 -c -o main.o main.cc /export/build/gnu/gcc/build-x86_64-linux/gcc/xg++ -B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -shared -fPIC -O2 -o libmv20.so mv20.cc -L/export/build/gnu/gcc/build-x86_64-linux/x86_64-unknown-linux-gnu/libstdc++-v3/src/.libs /export/build/gnu/gcc/build-x86_64-linux/gcc/xg++ -B/export/build/gnu/gcc/build-x86_64-linux/gcc/ -O2 -o x main.o libmv20.so -Wl,-R,. -L/export/build/gnu/gcc/build-x86_64-linux/x86_64-unknown-linux-gnu/libstdc++-v3/src/.libs /usr/local/bin/ld: x: hidden symbol `__cpu_model' in /export/build/gnu/gcc/build-x86_64-linux/gcc/libgcc_nonshared.a(cpuinfo.o) is referenced by DSO /usr/local/bin/ld: final link failed: Bad value collect2: error: ld returned 1 exit status >> @@ -424,3 +424,8 @@ __cpu_indicator_init (void) >> >> return 0; >> } >> + >> +#if defined SHARED && !defined _WIN32 >> +__asm__ (".symver __cpu_indicator_init, __cpu_indicator_init@GCC_4.8.0"); >> +__asm__ (".symver __cpu_model, __cpu_model@GCC_4.8.0"); >> +#endif > > Will this work on Solaris? > I'd say you at least want to also guard with some configure check if > .symver is supported by assembler. > I updated my patch with: @@ -424,3 +424,8 @@ __cpu_indicator_init (void) return 0; } + +#if defined SHARED && defined USE_ELF_SYMVER +__asm__ (".symver __cpu_indicator_init, __cpu_indicator_init@GCC_4.8.0"); +__asm__ (".symver __cpu_model, __cpu_model@GCC_4.8.0"); +#endif diff --git a/libgcc/config/i386/t-linux b/libgcc/config/i386/t-linux index 4f47f7b..11bb46e 100644 --- a/libgcc/config/i386/t-linux +++ b/libgcc/config/i386/t-linux @@ -3,4 +3,4 @@ # t-slibgcc-elf-ver and t-linux SHLIB_MAPFILES = libgcc-std.ver $(srcdir)/config/i386/libgcc-glibc.ver -HOST_LIBGCC2_CFLAGS += -mlong-double-80 +HOST_LIBGCC2_CFLAGS += -mlong-double-80 -DUSE_ELF_SYMVER OK for master? -- H.J.
From 259457afe0add56064ed49da1954d0770b1e1975 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" <hjl.to...@gmail.com> Date: Sun, 29 Mar 2015 18:03:49 -0700 Subject: [PATCH] Hide __cpu_indicator_init/__cpu_model from linker We shouldn't call external function, __cpu_indicator_init, while an object is being relocated since its .got.plt section hasn't been updated. It works for non-PIE since no update on .got.plt section is required. This patch hides __cpu_indicator_init/__cpu_model from linker to force linker to resolve __cpu_indicator_init/__cpu_model to their hidden definitions in libgcc_nonshared.a while providing backward binary compatibility. The new libgcc_nonshared.a is always linked togther with -lgcc_s and -lgcc. gcc/ PR target/65612 * gcc.c (init_spec): Add -lgcc_nonshared/libgcc_nonshared.a%s to -lgcc_s/-lgcc/libgcc.a%s. gcc/testsuite/ PR target/65612 * g++.dg/ext/mv18.C: New test. * g++.dg/ext/mv19.C: Likewise. * g++.dg/ext/mv20.C: Likewise. * g++.dg/ext/mv21.C: Likewise. * g++.dg/ext/mv22.C: Likewise. * g++.dg/ext/mv23.C: Likewise. libgcc/ PR target/65612 * Makefile.in (LIB2ADDSHARED): New. (LIB2ADDNONSHARED): Likewise. (libgcc-nonshared-objects): Likewise. (libgcc_nonshared.a): Likewise. Check unsupported files in LIB2ADDNONSHARED or LIB2ADDSHARED. (iter-items): Add $(LIB2ADDNONSHARED) $(LIB2ADDSHARED). (libgcc-s-objects): Add $(LIB2ADDSHARED). (all): Depend on libgcc_nonshared.a. ($(libgcc-nonshared-objects)): Depend on libgcc_tm.h. (install-leaf): Install libgcc_nonshared.a. * shared-object.mk: Check empty $o. * config/i386/cpuinfo.c (__cpu_model): Initialize. (__cpu_indicator_init@GCC_4.8.0): New. (__cpu_model@GCC_4.8.0): Likewise. * config/i386/t-cpuinfo (LIB2ADD): Renamed to ... (LIB2ADDSHARED): This. (LIB2ADDNONSHARED): New. * config/i386/t-linux (HOST_LIBGCC2_CFLAGS): Add -DUSE_ELF_SYMVER. --- gcc/gcc.c | 4 ++++ gcc/testsuite/g++.dg/ext/mv18.C | 7 +++++++ gcc/testsuite/g++.dg/ext/mv19.C | 7 +++++++ gcc/testsuite/g++.dg/ext/mv20.C | 7 +++++++ gcc/testsuite/g++.dg/ext/mv21.C | 7 +++++++ gcc/testsuite/g++.dg/ext/mv22.C | 7 +++++++ gcc/testsuite/g++.dg/ext/mv23.C | 7 +++++++ libgcc/Makefile.in | 28 ++++++++++++++++++++++++---- libgcc/config/i386/cpuinfo.c | 7 ++++++- libgcc/config/i386/t-cpuinfo | 3 ++- libgcc/config/i386/t-linux | 2 +- libgcc/shared-object.mk | 2 ++ 12 files changed, 81 insertions(+), 7 deletions(-) create mode 100644 gcc/testsuite/g++.dg/ext/mv18.C create mode 100644 gcc/testsuite/g++.dg/ext/mv19.C create mode 100644 gcc/testsuite/g++.dg/ext/mv20.C create mode 100644 gcc/testsuite/g++.dg/ext/mv21.C create mode 100644 gcc/testsuite/g++.dg/ext/mv22.C create mode 100644 gcc/testsuite/g++.dg/ext/mv23.C diff --git a/gcc/gcc.c b/gcc/gcc.c index d956c36..88a8dac 100644 --- a/gcc/gcc.c +++ b/gcc/gcc.c @@ -1566,11 +1566,13 @@ init_spec (void) if (in_sep && *p == '-' && strncmp (p, "-lgcc", 5) == 0) { init_gcc_specs (&obstack, + "-lgcc_nonshared " "-lgcc_s" #ifdef USE_LIBUNWIND_EXCEPTIONS " -lunwind" #endif , + "-lgcc_nonshared " "-lgcc", "-lgcc_eh" #ifdef USE_LIBUNWIND_EXCEPTIONS @@ -1591,7 +1593,9 @@ init_spec (void) /* Ug. We don't know shared library extensions. Hope that systems that use this form don't do shared libraries. */ init_gcc_specs (&obstack, + "libgcc_nonshared.a%s " "-lgcc_s", + "libgcc_nonshared.a%s " "libgcc.a%s", "libgcc_eh.a%s" #ifdef USE_LIBUNWIND_EXCEPTIONS diff --git a/gcc/testsuite/g++.dg/ext/mv18.C b/gcc/testsuite/g++.dg/ext/mv18.C new file mode 100644 index 0000000..1f024de --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv18.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target pie } */ +/* { dg-options "-O2 -fPIE -pie" } */ + +#include "mv1.C" diff --git a/gcc/testsuite/g++.dg/ext/mv19.C b/gcc/testsuite/g++.dg/ext/mv19.C new file mode 100644 index 0000000..d1ea788 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv19.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target pie } */ +/* { dg-options "-O2 -fPIE -pie -march=x86-64" } */ + +#include "mv14.C" diff --git a/gcc/testsuite/g++.dg/ext/mv20.C b/gcc/testsuite/g++.dg/ext/mv20.C new file mode 100644 index 0000000..98f7408 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv20.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target pie } */ +/* { dg-options "-O2 -fPIE -pie -march=x86-64" } */ + +#include "mv15.C" diff --git a/gcc/testsuite/g++.dg/ext/mv21.C b/gcc/testsuite/g++.dg/ext/mv21.C new file mode 100644 index 0000000..9708ad9 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv21.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target static } */ +/* { dg-options "-O2 -static" } */ + +#include "mv1.C" diff --git a/gcc/testsuite/g++.dg/ext/mv22.C b/gcc/testsuite/g++.dg/ext/mv22.C new file mode 100644 index 0000000..2550136 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv22.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target static } */ +/* { dg-options "-O2 -static -march=x86-64" } */ + +#include "mv14.C" diff --git a/gcc/testsuite/g++.dg/ext/mv23.C b/gcc/testsuite/g++.dg/ext/mv23.C new file mode 100644 index 0000000..f00afb0 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/mv23.C @@ -0,0 +1,7 @@ +/* Test case to check if Multiversioning works. */ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-require-ifunc "" } */ +/* { dg-require-effective-target static } */ +/* { dg-options "-O2 -static -march=x86-64" } */ + +#include "mv15.C" diff --git a/libgcc/Makefile.in b/libgcc/Makefile.in index 88ddfea..f6eb047 100644 --- a/libgcc/Makefile.in +++ b/libgcc/Makefile.in @@ -261,6 +261,14 @@ LIB2ADD = # Assembler files should have names ending in `.S'. LIB2ADD_ST = +# List of extra C and assembler files to add to shared libgcc2. +# Assembler files should have names ending in `.S'. +LIB2ADDSHARED = + +# List of extra C and assembler files to add to libgcc_nonshared.a. +# Assembler files should have names ending in `.S'. +LIB2ADDNONSHARED = + # Specify the directories to be searched for header files. # Both . and srcdir are used, in that order, # so that *config.h will be found in the compilation @@ -807,12 +815,19 @@ endif libgcc-objects += $(addsuffix $(objext),$(basename $(notdir $(LIB2ADD)))) libgcc-objects += $(addsuffix $(objext),$(basename $(notdir $(LIB2ADD_ST)))) +# Build LIB2ADDNONSHARED and LIB2ADDSHARED. +ifneq ($(filter-out %.c %.S %.asm,$(LIB2ADDNONSHARED) $(LIB2ADDSHARED)),) +$(error Unsupported files in LIB2ADDNONSHARED or LIB2ADDSHARED.) +endif + +libgcc-nonshared-objects += $(addsuffix $(objext),$(basename $(notdir $(LIB2ADDNONSHARED)))) + c_flags := -iter-items := $(LIB2ADD) $(LIB2ADD_ST) +iter-items := $(LIB2ADD) $(LIB2ADD_ST) $(LIB2ADDNONSHARED) $(LIB2ADDSHARED) include $(iterator) ifeq ($(enable_shared),yes) -libgcc-s-objects += $(addsuffix _s$(objext),$(basename $(notdir $(LIB2ADD)))) +libgcc-s-objects += $(addsuffix _s$(objext),$(basename $(notdir $(LIB2ADD) $(LIB2ADDSHARED)))) endif # Build LIB2ADDEH, LIB2ADDEHSTATIC, and LIB2ADDEHSHARED. If we don't have @@ -890,8 +905,9 @@ libgcc.a: $(libgcc-objects) libgcov.a: $(libgcov-objects) libunwind.a: $(libunwind-objects) libgcc_eh.a: $(libgcc-eh-objects) +libgcc_nonshared.a: $(libgcc-nonshared-objects) -libgcc.a libgcov.a libunwind.a libgcc_eh.a: +libgcc.a libgcov.a libunwind.a libgcc_eh.a libgcc_nonshared.a: -rm -f $@ objects="$(objects)"; \ @@ -905,7 +921,7 @@ libgcc.a libgcov.a libunwind.a libgcc_eh.a: $(RANLIB) $@ -all: libgcc.a libgcov.a +all: libgcc.a libgcc_nonshared.a libgcov.a ifneq ($(LIBUNWIND),) all: libunwind.a @@ -1051,6 +1067,7 @@ libgcc-extra-parts: $(EXTRA_PARTS) all: $(extra-parts) $(libgcc-objects) $(libgcc-s-objects) $(libgcc-eh-objects) \ + $(libgcc-nonshared-objects) \ $(libgcov-objects) \ $(libunwind-objects) $(libunwind-s-objects) \ $(EXTRA_PARTS): libgcc_tm.h @@ -1118,6 +1135,9 @@ install-leaf: $(install-shared) $(install-libunwind) $(INSTALL_DATA) libgcc.a $(DESTDIR)$(inst_libdir)/ chmod 644 $(DESTDIR)$(inst_libdir)/libgcc.a $(RANLIB) $(DESTDIR)$(inst_libdir)/libgcc.a + $(INSTALL_DATA) libgcc_nonshared.a $(DESTDIR)$(inst_libdir)/ + chmod 644 $(DESTDIR)$(inst_libdir)/libgcc_nonshared.a + $(RANLIB) $(DESTDIR)$(inst_libdir)/libgcc_nonshared.a $(INSTALL_DATA) libgcov.a $(DESTDIR)$(inst_libdir)/ chmod 644 $(DESTDIR)$(inst_libdir)/libgcov.a $(RANLIB) $(DESTDIR)$(inst_libdir)/libgcov.a diff --git a/libgcc/config/i386/cpuinfo.c b/libgcc/config/i386/cpuinfo.c index eaf2f10..f6f91dd 100644 --- a/libgcc/config/i386/cpuinfo.c +++ b/libgcc/config/i386/cpuinfo.c @@ -109,7 +109,7 @@ struct __processor_model unsigned int __cpu_type; unsigned int __cpu_subtype; unsigned int __cpu_features[1]; -} __cpu_model; +} __cpu_model = { }; /* Get the specific type of AMD CPU. */ @@ -424,3 +424,8 @@ __cpu_indicator_init (void) return 0; } + +#if defined SHARED && defined USE_ELF_SYMVER +__asm__ (".symver __cpu_indicator_init, __cpu_indicator_init@GCC_4.8.0"); +__asm__ (".symver __cpu_model, __cpu_model@GCC_4.8.0"); +#endif diff --git a/libgcc/config/i386/t-cpuinfo b/libgcc/config/i386/t-cpuinfo index 31c8db9..8dbe9e6 100644 --- a/libgcc/config/i386/t-cpuinfo +++ b/libgcc/config/i386/t-cpuinfo @@ -1 +1,2 @@ -LIB2ADD += $(srcdir)/config/i386/cpuinfo.c +LIB2ADDSHARED += $(srcdir)/config/i386/cpuinfo.c +LIB2ADDNONSHARED += $(srcdir)/config/i386/cpuinfo.c diff --git a/libgcc/config/i386/t-linux b/libgcc/config/i386/t-linux index 4f47f7b..11bb46e 100644 --- a/libgcc/config/i386/t-linux +++ b/libgcc/config/i386/t-linux @@ -3,4 +3,4 @@ # t-slibgcc-elf-ver and t-linux SHLIB_MAPFILES = libgcc-std.ver $(srcdir)/config/i386/libgcc-glibc.ver -HOST_LIBGCC2_CFLAGS += -mlong-double-80 +HOST_LIBGCC2_CFLAGS += -mlong-double-80 -DUSE_ELF_SYMVER diff --git a/libgcc/shared-object.mk b/libgcc/shared-object.mk index efac797..306176d 100644 --- a/libgcc/shared-object.mk +++ b/libgcc/shared-object.mk @@ -4,6 +4,7 @@ o := $(firstword $(iter-items)) iter-items := $(filter-out $o,$(iter-items)) +ifneq ($o,) base := $(basename $(notdir $o)) c_flags-$o := $(c_flags) @@ -36,3 +37,4 @@ $(base)_s$(objext): $o $(gcc_s_compile) -c $(as_flags-$<) $< endif +endif -- 2.1.0