[PATCH] Gold: Do not emit locals from discard .eh_frame sections.
Doug Kwan (關振德)
dougkwan@google.com
Fri Jun 5 00:45:00 GMT 2009
Hi,
This patches fixes a bug in which gold attempts to output local
symbols from discarded .eh_frame sections and triggers an assert in
Output_section::output_address because the function cannot find
corresponding input sections for those symbols. This passed all gold
tests on x86_64-unknown-linux-gnu, including a new test in this patch.
-Doug
2009-06-04 Doug Kwan <dougkwan@google.com>
* object.cc (Sized_relobj::Sized_relobj): Initialize
discarded_eh_frame_shndx_ to -1U.
(Sized_relobj::do_layout): Record index of a discard .eh_frame
section.
(Sized_relobj::do_count_local_symbols): Skip local symbols in
a discarded .eh_frame section.
(Sized_relobj::do_finalize_local_symbols): Ditto.
* object.h (class Sized_relobj): Declare new member
discarded_eh_frame_shndx_.
* testsuite/Makefile.am (check_PROGRAMS): Add local_labels_test.
(local_labels_test_SOURCE, local_labels_test_LDFLAGS): Define new.
(local_labels_test.o): New rule.
* testsuite/Makefile.in: Regenerate.
* testsuite/local_labels_test.cc: New file.
-------------- next part --------------
Index: gold/object.cc
===================================================================
RCS file: /cvs/src/src/gold/object.cc,v
retrieving revision 1.91
diff -u -u -p -r1.91 object.cc
--- gold/object.cc 22 May 2009 18:31:22 -0000 1.91
+++ gold/object.cc 5 Jun 2009 00:30:22 -0000
@@ -327,7 +327,8 @@ Sized_relobj<size, big_endian>::Sized_re
local_values_(),
local_got_offsets_(),
kept_comdat_sections_(),
- has_eh_frame_(false)
+ has_eh_frame_(false),
+ discarded_eh_frame_shndx_(-1U)
{
}
@@ -1295,7 +1296,12 @@ Sized_relobj<size, big_endian>::do_layou
&offset);
out_sections[i] = os;
if (offset == -1)
- out_section_offsets[i] = invalid_address;
+ {
+ // There can be at most one .eh_frame section per object.
+ gold_assert(this->discarded_eh_frame_shndx_ == -1U);
+ this->discarded_eh_frame_shndx_ = i;
+ out_section_offsets[i] = invalid_address;
+ }
else
out_section_offsets[i] = convert_types<Address, off_t>(offset);
@@ -1453,7 +1459,8 @@ Sized_relobj<size, big_endian>::do_count
// Decide whether this symbol should go into the output file.
- if (shndx < shnum && out_sections[shndx] == NULL)
+ if ((shndx < shnum && out_sections[shndx] == NULL)
+ || (shndx == this->discarded_eh_frame_shndx_))
{
lv.set_no_output_symtab_entry();
gold_assert(!lv.needs_output_dynsym_entry());
@@ -1558,7 +1565,15 @@ Sized_relobj<size, big_endian>::do_final
// This is a SHF_MERGE section or one which otherwise
// requires special handling.
- if (!lv.is_section_symbol())
+ if (shndx == this->discarded_eh_frame_shndx_)
+ {
+ // This local symbol belongs to a discarded .eh_frame
+ // section. Just treat it like the case in which
+ // os == NULL above.
+ gold_assert(this->has_eh_frame_);
+ continue;
+ }
+ else if (!lv.is_section_symbol())
{
// This is not a section symbol. We can determine
// the final value now.
Index: gold/object.h
===================================================================
RCS file: /cvs/src/src/gold/object.h,v
retrieving revision 1.74
diff -u -u -p -r1.74 object.h
--- gold/object.h 19 May 2009 22:14:17 -0000 1.74
+++ gold/object.h 5 Jun 2009 00:30:22 -0000
@@ -1815,6 +1815,9 @@ class Sized_relobj : public Relobj
Kept_comdat_section_table kept_comdat_sections_;
// Whether this object has a GNU style .eh_frame section.
bool has_eh_frame_;
+ // If this object has a GNU sytle .eh_frame section that is discarded in
+ // output, record the index here. Otherwise it is -1U.
+ unsigned int discarded_eh_frame_shndx_;
// The list of sections whose layout was deferred.
std::vector<Deferred_layout> deferred_layout_;
};
Index: gold/testsuite/Makefile.am
===================================================================
RCS file: /cvs/src/src/gold/testsuite/Makefile.am,v
retrieving revision 1.91
diff -u -u -p -r1.91 Makefile.am
--- gold/testsuite/Makefile.am 26 May 2009 22:52:56 -0000 1.91
+++ gold/testsuite/Makefile.am 5 Jun 2009 00:30:23 -0000
@@ -1074,5 +1074,11 @@ alt/libexclude_libs_test_3.a: exclude_li
test -d alt || mkdir -p alt
$(TEST_AR) rc $@ $^
+check_PROGRAMS += local_labels_test
+local_labels_test_SOURCES = local_labels_test.cc
+local_labels_test_LDFLAGS = -Bgcctestdir/
+local_labels_test.o: local_labels_test.cc
+ $(CXXCOMPILE) -g -c -Wa,--keep-locals -o $@ $<
+
endif GCC
endif NATIVE_LINKER
Index: gold/testsuite/Makefile.in
===================================================================
RCS file: /cvs/src/src/gold/testsuite/Makefile.in,v
retrieving revision 1.96
diff -u -u -p -r1.96 Makefile.in
--- gold/testsuite/Makefile.in 26 May 2009 22:52:56 -0000 1.96
+++ gold/testsuite/Makefile.in 5 Jun 2009 00:30:23 -0000
@@ -318,7 +318,8 @@ check_PROGRAMS = object_unittest$(EXEEXT
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_test_2.err \
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_test_3.err \
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_test_4.err
-@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_24 = exclude_libs_test
+@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_24 = exclude_libs_test \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ local_labels_test
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_25 = exclude_libs_test.sh
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_26 = exclude_libs_test.syms
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_27 = exclude_libs_test.syms libexclude_libs_test_1.a \
@@ -429,7 +430,8 @@ libgoldtest_a_OBJECTS = $(am_libgoldtest
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_test_3$(EXEEXT) \
@GCC_TRUE@@NATIVE_LINKER_TRUE@@PLUGINS_TRUE@ plugin_test_4$(EXEEXT)
@GCC_TRUE@@NATIVE_LINKER_TRUE@am__EXEEXT_17 = \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@ exclude_libs_test$(EXEEXT)
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ exclude_libs_test$(EXEEXT) \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ local_labels_test$(EXEEXT)
basic_pic_test_SOURCES = basic_pic_test.c
basic_pic_test_OBJECTS = basic_pic_test.$(OBJEXT)
basic_pic_test_LDADD = $(LDADD)
@@ -573,6 +575,14 @@ am__justsyms_SOURCES_DIST = justsyms_1.c
@GCC_TRUE@@NATIVE_LINKER_TRUE@ justsyms_1.$(OBJEXT)
justsyms_OBJECTS = $(am_justsyms_OBJECTS)
justsyms_LDADD = $(LDADD)
+am__local_labels_test_SOURCES_DIST = local_labels_test.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@am_local_labels_test_OBJECTS = \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ local_labels_test.$(OBJEXT)
+local_labels_test_OBJECTS = $(am_local_labels_test_OBJECTS)
+local_labels_test_LDADD = $(LDADD)
+local_labels_test_DEPENDENCIES = libgoldtest.a ../libgold.a \
+ ../../libiberty/libiberty.a $(am__DEPENDENCIES_1) \
+ $(am__DEPENDENCIES_1) $(am__DEPENDENCIES_1)
many_sections_r_test_SOURCES = many_sections_r_test.c
many_sections_r_test_OBJECTS = many_sections_r_test.$(OBJEXT)
many_sections_r_test_LDADD = $(LDADD)
@@ -900,7 +910,8 @@ SOURCES = $(libgoldtest_a_SOURCES) basic
$(exclude_libs_test_SOURCES) \
flagstest_compress_debug_sections.c flagstest_o_specialfile.c \
flagstest_o_specialfile_and_compress_debug_sections.c \
- $(initpri1_SOURCES) $(justsyms_SOURCES) many_sections_r_test.c \
+ $(initpri1_SOURCES) $(justsyms_SOURCES) \
+ $(local_labels_test_SOURCES) many_sections_r_test.c \
$(many_sections_test_SOURCES) $(object_unittest_SOURCES) \
plugin_test_1.c plugin_test_2.c plugin_test_3.c \
plugin_test_4.c $(protected_1_SOURCES) $(protected_2_SOURCES) \
@@ -955,7 +966,8 @@ DIST_SOURCES = $(libgoldtest_a_SOURCES)
flagstest_compress_debug_sections.c flagstest_o_specialfile.c \
flagstest_o_specialfile_and_compress_debug_sections.c \
$(am__initpri1_SOURCES_DIST) $(am__justsyms_SOURCES_DIST) \
- many_sections_r_test.c $(am__many_sections_test_SOURCES_DIST) \
+ $(am__local_labels_test_SOURCES_DIST) many_sections_r_test.c \
+ $(am__many_sections_test_SOURCES_DIST) \
$(object_unittest_SOURCES) plugin_test_1.c plugin_test_2.c \
plugin_test_3.c plugin_test_4.c \
$(am__protected_1_SOURCES_DIST) \
@@ -1519,6 +1531,8 @@ binary_unittest_SOURCES = binary_unittes
@GCC_TRUE@@NATIVE_LINKER_TRUE@exclude_libs_test_LDADD = -lexclude_libs_test_1 -lexclude_libs_test_2 \
@GCC_TRUE@@NATIVE_LINKER_TRUE@ alt/libexclude_libs_test_3.a
+@GCC_TRUE@@NATIVE_LINKER_TRUE@local_labels_test_SOURCES = local_labels_test.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@local_labels_test_LDFLAGS = -Bgcctestdir/
all: $(BUILT_SOURCES)
$(MAKE) $(AM_MAKEFLAGS) all-am
@@ -1659,6 +1673,9 @@ initpri1$(EXEEXT): $(initpri1_OBJECTS) $
justsyms$(EXEEXT): $(justsyms_OBJECTS) $(justsyms_DEPENDENCIES)
@rm -f justsyms$(EXEEXT)
$(CXXLINK) $(justsyms_LDFLAGS) $(justsyms_OBJECTS) $(justsyms_LDADD) $(LIBS)
+local_labels_test$(EXEEXT): $(local_labels_test_OBJECTS) $(local_labels_test_DEPENDENCIES)
+ @rm -f local_labels_test$(EXEEXT)
+ $(CXXLINK) $(local_labels_test_LDFLAGS) $(local_labels_test_OBJECTS) $(local_labels_test_LDADD) $(LIBS)
@GCC_FALSE@many_sections_r_test$(EXEEXT): $(many_sections_r_test_OBJECTS) $(many_sections_r_test_DEPENDENCIES)
@GCC_FALSE@ @rm -f many_sections_r_test$(EXEEXT)
@GCC_FALSE@ $(LINK) $(many_sections_r_test_LDFLAGS) $(many_sections_r_test_OBJECTS) $(many_sections_r_test_LDADD) $(LIBS)
@@ -1891,6 +1908,7 @@ distclean-compile:
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/flagstest_o_specialfile_and_compress_debug_sections.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/initpri1.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/justsyms_1.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/local_labels_test.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/many_sections_r_test.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/many_sections_test.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/object_unittest.Po@am__quote@
@@ -2613,6 +2631,8 @@ uninstall-am: uninstall-info-am
@GCC_TRUE@@NATIVE_LINKER_TRUE@alt/libexclude_libs_test_3.a: exclude_libs_test_3.o
@GCC_TRUE@@NATIVE_LINKER_TRUE@ test -d alt || mkdir -p alt
@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(TEST_AR) rc $@ $^
+@GCC_TRUE@@NATIVE_LINKER_TRUE@local_labels_test.o: local_labels_test.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ $(CXXCOMPILE) -g -c -Wa,--keep-locals -o $@ $<
# Tell versions [3.59,3.63) of GNU make to not export all variables.
# Otherwise a system limit (for SysV at least) may be exceeded.
.NOEXPORT:
Index: gold/testsuite/local_labels_test.cc
===================================================================
RCS file: gold/testsuite/local_labels_test.cc
diff -N gold/testsuite/local_labels_test.cc
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gold/testsuite/local_labels_test.cc 5 Jun 2009 00:30:23 -0000
@@ -0,0 +1,32 @@
+// local_labels_test.cc -- test case for local labels in .eh_frame sections.
+
+// Copyright 2009 Free Software Foundation, Inc.
+// Written by Doug Kwan <dougkwan@google.com>.
+
+// This file is part of gold.
+
+// This program 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 of the License, or
+// (at your option) any later version.
+
+// This program 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 program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+// This is assembled with the -Wa,--keep-locals option to preserve all
+// local labels in the object. gold had a bug in which local symbols from
+// discarded .eh_frame sections were not removed. Those local symbols caused
+// gold to abort because no output sections were found.
+
+int
+main (int, char**)
+{
+ return 0;
+}
More information about the Binutils
mailing list