Fix problem where version script causes predefined hidden symbol to be defined twice.

When creating a predefined hidden symbol like _GLOBAL_OFFSET_TABLE_, gold
was incorrectly letting a version script add a version to the symbol,
resulting in two copies of the symbol, both STB_LOCAL, but one of which
was grouped in the globals part of the symbol table.

gold/
	* symtab.cc (Symbol_table::define_special_symbol): Add is_forced_local
	parameter; if set, do not check version script.
	(Symbol_table::do_define_in_output_data): Pass is_forced_local for
	STB_LOCAL predefined symbols.
	(Symbol_table::do_define_in_output_segment): Likewise.
	(Symbol_table::do_define_in_output_segment): Likewise.
	(Symbol_table::do_define_as_constant): Likewise.
	* symtab.h (Symbol_table::define_special_symbol): Add is_forced_local
	parameter. Adjust all callers.
	* testsuite/Makefile.am (ver_test_8.sh): New test case.
	* testsuite/Makefile.in: Regenerate.
	* ver_test_8.sh: New test script.

3 files changed, 47 insertions, 3 deletions

diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index 7d91575..fbdc147 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -1739,6 +1739,11 @@ ver_test_8_1.so: two_file_test_1_pic.o two_file_test_1b_pic.o ver_test_8_2.so gc
 ver_test_8_2.so: two_file_test_2_pic.o $(srcdir)/ver_test_8.script gcctestdir/ld
 	$(CXXLINK) -Bgcctestdir/ -shared -Wl,--version-script,$(srcdir)/ver_test_8.script two_file_test_2_pic.o
 
+check_SCRIPTS += ver_test_8.sh
+check_DATA += ver_test_8_2.so.syms
+ver_test_8_2.so.syms: ver_test_8_2.so
+	$(TEST_READELF) -s $< >$@ 2>/dev/null
+
 check_PROGRAMS += ver_test_9
 ver_test_9_SOURCES = ver_test_main.cc
 ver_test_9_DEPENDENCIES = gcctestdir/ld ver_test_9.so
diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index a385ad4..d1ce1fb 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -409,8 +409,9 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	undef_symbol.sh pr18689.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_1.sh ver_test_2.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_4.sh ver_test_5.sh \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_7.sh ver_test_10.sh \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_13.sh relro_test.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_7.sh ver_test_8.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_10.sh ver_test_13.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	relro_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_matching_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_3.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_4.sh \
@@ -461,7 +462,9 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	flagstest_o_ttext_2 \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_1.syms ver_test_2.syms \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_4.syms ver_test_5.syms \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_7.syms ver_test_10.syms \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_7.syms \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_8_2.so.syms \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_10.syms \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_13.syms protected_3.err \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	relro_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_matching_test.stdout \
@@ -5118,6 +5121,8 @@ ver_test_5.sh.log: ver_test_5.sh
 	@p='ver_test_5.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 ver_test_7.sh.log: ver_test_7.sh
 	@p='ver_test_7.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
+ver_test_8.sh.log: ver_test_8.sh
+	@p='ver_test_8.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 ver_test_10.sh.log: ver_test_10.sh
 	@p='ver_test_10.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 ver_test_13.sh.log: ver_test_13.sh
@@ -6578,6 +6583,8 @@ uninstall-am:
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -shared two_file_test_1_pic.o two_file_test_1b_pic.o ver_test_8_2.so
 @GCC_TRUE@@NATIVE_LINKER_TRUE@ver_test_8_2.so: two_file_test_2_pic.o $(srcdir)/ver_test_8.script gcctestdir/ld
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -shared -Wl,--version-script,$(srcdir)/ver_test_8.script two_file_test_2_pic.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@ver_test_8_2.so.syms: ver_test_8_2.so
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_READELF) -s $< >$@ 2>/dev/null
 @GCC_TRUE@@NATIVE_LINKER_TRUE@ver_test_9.so: ver_test_9.o ver_test_4.so ver_test_5.so gcctestdir/ld
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -shared -Wl,-R,. ver_test_9.o ver_test_5.so ver_test_4.so
 @GCC_TRUE@@NATIVE_LINKER_TRUE@ver_test_9.o: ver_test_9.cc
diff --git a/gold/testsuite/ver_test_8.sh b/gold/testsuite/ver_test_8.sh
new file mode 100755
index 0000000..4f46e3c
--- /dev/null
+++ b/gold/testsuite/ver_test_8.sh
@@ -0,0 +1,32 @@
+#!/bin/sh
+
+# ver_test_8.sh -- check that __GLOBAL_OFFSET_TABLE__ is defined only once.
+
+# Copyright (C) 2016 Free Software Foundation, Inc.
+# Written by Cary Coutant <ccoutant@gmail.com>.
+
+# This file is part of gold.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+
+count=`grep -c '_GLOBAL_OFFSET_TABLE_' ver_test_8_2.so.syms`
+
+if test "$count" -ne 1; then
+  echo "Found $count copies of '_GLOBAL_OFFSET_TABLE_' (should be only 1)"
+  exit 1
+fi
+
+exit 0