* layout.cc (Layout::layout): If we see an input section with a

	name that needs sorting, set the must_sort flag for the output
	section.
	(Layout::make_output_section): If the name of the output section
	indicates that it might	require sorting, set the may_sort flag.
	* output.h (Output_section::may_sort_attached_input_sections): New
	function.
	(Output_section::set_may_sort_attached_input_sections): New
	function.
	(Output_section::must_sort_attached_input_sections): New
	function.
	(Output_section::set_must_sort_attached_input_sections): New
	function.
	(class Output_section): Declare Input_section_sort_entry.  Define
	Input_section_sort_compare.  Declare
	sort_attached_input_sections.  Add new fields:
	may_sort_attached_input_sections_,
	must_sort_attached_input_sections_,
	attached_input_sections_are_sorted_.
	* output.cc (Output_section::Output_section): Initialize new
	fields.
	(Output_section::add_input_section): Add an entry to
	input_sections_ if may_sort or must_sort are true.
	(Output_section::set_final_data_size): Call
	sort_attached_input_sections if necessary.
	(Output_section::Input_section_sort_entry): Define new class.
	(Output_section::Input_section_sort_compare::operator()): New
	function.
	(Output_section::sort_attached_input_sections): New function.
	* configure.ac: Check whether the compiler supports constructor
	priorities.  Define a CONSTRUCTOR_PRIORITY automake conditional.
	* testsuite/initpri1.c: New file.
	* testsuite/Makefile.am (check_PROGRAMS): Add initpri1 if
	CONSTRUCTOR_PRIORITY.
	(initpri1_SOURCES, initpri1_DEPENDENCIES): New variables.
	(initpri1_LDFLAGS): New variable.
	* configure, Makefile.in, testsuite/Makefile.in: Rebuild.

1 files changed, 21 insertions, 0 deletions

diff --git a/gold/layout.cc b/gold/layout.cc
index 1bbfcb6..e8582ca 100644
--- a/gold/layout.cc
+++ b/gold/layout.cc
@@ -404,6 +404,17 @@ Layout::layout(Sized_relobj<size, big_endian>* object, unsigned int shndx,
 	return NULL;
     }
 
+  // By default the GNU linker sorts input sections whose names match
+  // .ctor.*, .dtor.*, .init_array.*, or .fini_array.*.  The sections
+  // are sorted by name.  This is used to implement constructor
+  // priority ordering.  We are compatible.
+  if (!this->script_options_->saw_sections_clause()
+      && (is_prefix_of(".ctors.", name)
+	  || is_prefix_of(".dtors.", name)
+	  || is_prefix_of(".init_array.", name)
+	  || is_prefix_of(".fini_array.", name)))
+    os->set_must_sort_attached_input_sections();
+
   // FIXME: Handle SHF_LINK_ORDER somewhere.
 
   *off = os->add_input_section(object, shndx, name, shdr, reloc_shndx,
@@ -671,6 +682,16 @@ Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
   else
     this->attach_to_segment(os, flags);
 
+  // The GNU linker by default sorts some sections by priority, so we
+  // do the same.  We need to know that this might happen before we
+  // attach any input sections.
+  if (!this->script_options_->saw_sections_clause()
+      && (strcmp(name, ".ctors") == 0
+	  || strcmp(name, ".dtors") == 0
+	  || strcmp(name, ".init_array") == 0
+	  || strcmp(name, ".fini_array") == 0))
+    os->set_may_sort_attached_input_sections();
+
   return os;
 }