* gc.h (Garbage_collection::Cident_section_map): New typedef.

	(Garbage_collection::cident_sections): New function.
	(Garbage_collection::add_cident_section): New function.
	(Garbage_collection::cident_sections_): New member.
	(gc_process_relocs): Add references to sections whose names are C
	identifiers.
	* gold.h (cident_section_start_prefix): New constant.
	(cident_section_stop_prefix): New constant.
	(is_cident): New function.
	* layout.cc (Layout::define_section_symbols): Replace string constants
	with the newly defined constants.
	* object.cc (Sized_relobj::do_layout): Track sections whose names are
	C identifiers.
	* testsuite/Makefile.am: Add gc_orphan_section_test.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/gc_orphan_section_test.cc: New file.
	* testsuite/gc_orphan_section_test.sh: New file.

4 files changed, 102 insertions, 1 deletions

diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index 7b5532e..2bf5bbe 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -139,6 +139,16 @@ gc_tls_test:gc_tls_test.o gcctestdir/ld
 gc_tls_test.stdout: gc_tls_test
 	$(TEST_NM) -C gc_tls_test > gc_tls_test.stdout
 
+check_SCRIPTS += gc_orphan_section_test.sh
+check_DATA += gc_orphan_section_test.stdout
+MOSTLYCLEANFILES += gc_orphan_section_test
+gc_orphan_section_test.o: gc_orphan_section_test.cc
+	$(CXXCOMPILE) -O0 -c -g -o $@ $<
+gc_orphan_section_test:gc_orphan_section_test.o gcctestdir/ld
+	$(CXXLINK) -Bgcctestdir/ -Wl,--gc-sections gc_orphan_section_test.o
+gc_orphan_section_test.stdout: gc_orphan_section_test
+	$(TEST_NM) gc_orphan_section_test > gc_orphan_section_test.stdout
+
 check_SCRIPTS += icf_test.sh
 check_DATA += icf_test.stdout
 MOSTLYCLEANFILES += icf_test
diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index 291eab7..21fca3d 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -57,6 +57,7 @@ check_PROGRAMS = object_unittest$(EXEEXT) binary_unittest$(EXEEXT) \
 # and --dynamic-list-cpp-typeinfo
 @GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_1 = incremental_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_comdat_test.sh gc_tls_test.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_orphan_section_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_keep_unique_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_safe_test.sh \
@@ -82,6 +83,7 @@ check_PROGRAMS = object_unittest$(EXEEXT) binary_unittest$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_2 = incremental_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_comdat_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_tls_test.stdout \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_orphan_section_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_keep_unique_test.stdout \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_safe_test.stdout \
@@ -103,7 +105,8 @@ check_PROGRAMS = object_unittest$(EXEEXT) binary_unittest$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	dynamic_list.stdout
 @GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_3 = incremental_test \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_comdat_test gc_tls_test \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_test icf_keep_unique_test \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_orphan_section_test icf_test \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_keep_unique_test \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	icf_safe_test \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	two_file_shared.dbg \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	alt/weak_undef_lib.so
@@ -2582,6 +2585,12 @@ uninstall-am:
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -Wl,--gc-sections gc_tls_test.o
 @GCC_TRUE@@NATIVE_LINKER_TRUE@gc_tls_test.stdout: gc_tls_test
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_NM) -C gc_tls_test > gc_tls_test.stdout
+@GCC_TRUE@@NATIVE_LINKER_TRUE@gc_orphan_section_test.o: gc_orphan_section_test.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -O0 -c -g -o $@ $<
+@GCC_TRUE@@NATIVE_LINKER_TRUE@gc_orphan_section_test:gc_orphan_section_test.o gcctestdir/ld
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -Wl,--gc-sections gc_orphan_section_test.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@gc_orphan_section_test.stdout: gc_orphan_section_test
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(TEST_NM) gc_orphan_section_test > gc_orphan_section_test.stdout
 @GCC_TRUE@@NATIVE_LINKER_TRUE@icf_test.o: icf_test.cc 
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -O0 -c -ffunction-sections -g -o $@ $<
 @GCC_TRUE@@NATIVE_LINKER_TRUE@icf_test: icf_test.o gcctestdir/ld
diff --git a/gold/testsuite/gc_orphan_section_test.cc b/gold/testsuite/gc_orphan_section_test.cc
new file mode 100644
index 0000000..3443f8d
--- /dev/null
+++ b/gold/testsuite/gc_orphan_section_test.cc
@@ -0,0 +1,36 @@
+// gc_orphan_section_test.cc -- a test case for gold
+
+// Copyright 2010 Free Software Foundation, Inc.
+// Written by Sriraman Tallam <tmsriram@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.
+
+// The goal of this program is to verify if garbage collection does not
+// discard orphan sections when references to them through __start_XXX
+// and __stop_XXX are present.  Here section _foo must not be gc'ed but
+// _boo should be gc'ed.
+
+extern const int *__start__foo;
+int foo __attribute__((__section__("_foo"))) = 1;
+int boo __attribute__((__section__("_boo"))) = 1;
+
+int main()
+{
+  return *__start__foo;
+}
+
diff --git a/gold/testsuite/gc_orphan_section_test.sh b/gold/testsuite/gc_orphan_section_test.sh
new file mode 100755
index 0000000..6ce524d
--- /dev/null
+++ b/gold/testsuite/gc_orphan_section_test.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# gc_orphan_section_test.sh -- test --gc-sections
+
+# Copyright 2010 Free Software Foundation, Inc.
+# Written by Sriraman Tallam <tmsriram@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.
+
+# The goal of this program is to verify if gc-sections works as expected
+# with orphan sections.
+# File gc_orphan_sections_test.cc is in this test. This program checks if
+# the orphan sections are retained when they are referenced through
+# __start_XXX and __stop_XXX symbols.
+
+check()
+{
+    if grep -q " boo" "$1"
+    then
+        echo "Garbage collection failed to collect boo"
+	exit 1
+    fi
+    grep_foo=`grep -q " foo" $1`
+    if [ $? != 0 ];
+    then
+        echo "Garbage collection should not discard foo"
+	exit 1
+    fi
+}
+
+check gc_orphan_section_test.stdout