Fix problem where mixed section types can cause internal error during a -r link.

During a -r (or --emit-relocs) link, if two sections had the same name but
different section types, gold would put relocations for both sections into
the same relocation section even though the data sections remained separate.

For .eh_frame sections, when one section is PROGBITS and another is
X86_64_UNWIND, we really should be using the UNWIND section type and
combining the sections anyway.  For other sections, we should be
creating one relocation section for each output data section.

gold/
	PR gold/23016
	* incremental.cc (can_incremental_update): Check for unwind section
	type.
	* layout.h (Layout::layout): Add sh_type parameter.
	* layout.cc (Layout::layout): Likewise.
	(Layout::layout_reloc): Create new output reloc section if data
	section does not already have one.
	(Layout::layout_eh_frame): Check for unwind section type.
	(Layout::make_eh_frame_section): Use unwind section type for .eh_frame
	and .eh_frame_hdr.
	* object.h (Sized_relobj_file::Shdr_write): New typedef.
	(Sized_relobj_file::layout_section): Add sh_type parameter.
	(Sized_relobj_file::Deferred_layout::Deferred_layout): Add sh_type
	parameter.
	* object.cc (Sized_relobj_file::check_eh_frame_flags): Check for
	unwind section type.
	(Sized_relobj_file::layout_section): Add sh_type parameter; pass it
	to Layout::layout.
	(Sized_relobj_file::do_layout): Make local copy of sh_type.
	Force .eh_frame sections to unwind section type.
	Pass sh_type to layout_section.
	(Sized_relobj_file<size, big_endian>::do_layout_deferred_sections):
	Pass sh_type to layout_section.
	* output.cc (Output_section::Output_section): Initialize reloc_section_.
	* output.h (Output_section::reloc_section): New method.
	(Output_section::set_reloc_section): New method.
	(Output_section::reloc_section_): New data member.
	* target.h (Target::unwind_section_type): New method.
	(Target::Target_info::unwind_section_type): New data member.

	* aarch64.cc (aarch64_info): Add unwind_section_type.
	* arm.cc (arm_info, arm_nacl_info): Likewise.
	* i386.cc (i386_info, i386_nacl_info, iamcu_info): Likewise.
	* mips.cc (mips_info, mips_nacl_info): Likewise.
	* powerpc.cc (powerpc_info): Likewise.
	* s390.cc (s390_info): Likewise.
	* sparc.cc (sparc_info): Likewise.
	* tilegx.cc (tilegx_info): Likewise.
	* x86_64.cc (x86_64_info, x86_64_nacl_info): Likewise.

	* testsuite/Makefile.am (pr23016_1, pr23016_2): New test cases.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/testfile.cc: Add unwind_section_type.
	* testsuite/pr23016_1.sh: New test script.
	* testsuite/pr23016_1a.s: New source file.
	* testsuite/pr23016_1b.s: New source file.
	* testsuite/pr23016_2.sh: New test script.
	* testsuite/pr23016_2a.s: New source file.
	* testsuite/pr23016_2b.s: New source file.

1 files changed, 8 insertions, 0 deletions

diff --git a/gold/target.h b/gold/target.h
index 059d2d0..da2f6bb 100644
--- a/gold/target.h
+++ b/gold/target.h
@@ -474,6 +474,11 @@ class Target
   hash_entry_size() const
   { return this->pti_->hash_entry_size; }
 
+  // Return the section type to use for unwind sections.
+  unsigned int
+  unwind_section_type() const
+  { return this->pti_->unwind_section_type; }
+
   // Whether the target has a custom set_dynsym_indexes method.
   bool
   has_custom_set_dynsym_indexes() const
@@ -562,6 +567,9 @@ class Target
     // Size (in bits) of SHT_HASH entry. Always equal to 32, except for
     // 64-bit S/390.
     const int hash_entry_size;
+    // Processor-specific section type for ".eh_frame" (unwind) sections.
+    // SHT_PROGBITS if there is no special section type.
+    const unsigned int unwind_section_type;
   };
 
   Target(const Target_info* pti)