Make default compression gABI compliant

All programs in binutils+gdb git repo now support gABI compression
with the SHF_COMPRESSED bit.  This patch makes the zlib-gabi option
as compression default for gas, gold, ld and objcopy, instead of the
zlib-gnu option whose outputs are incompatible with gABI.

binutils/

	* objcopy.c (copy_file): Set BFD_COMPRESS_GABI if not
	zlib-gnu.
	* doc/binutils.texi: Change --compress-debug-sections and
	--compress-debug-sections=zlib to zlib-gabi.

binutils/testsuite/

	* binutils-all/compress.exp: Update.

gas/

	* as.c (parse_args): Make --compress-debug-sections and
	--compress-debug-sections=zlib the same as
	--compress-debug-sections=zlib-gabi.
	* doc/as.texinfo: Change --compress-debug-sections and
	--compress-debug-sections=zlib to zlib-gabi.

gold/

	* compressed_output.cc (Output_compressed_section::set_final_data_size):
	Make --compress-debug-sections=zlib the same as
	--compress-debug-sections=zlib-gabi.
	* testsuite/Makefile.am (flagstest_compress_debug_sections.check):
	Expect ".debug_.*" with the SHF_COMPRESSED bit, instead of
	".zdebug_".
	* testsuite/Makefile.in: Regenerated.

ld/

	* emultempl/elf32.em (gld${EMULATION_NAME}_handle_option): Make
	--compress-debug-sections=zlib the same as
	--compress-debug-sections=zlib-gabi.
	* ld.texinfo: Change --compress-debug-sections=zlib to zlib-gabi.

ld/testsuite/

	* ld-elf/zlibbegin.rS: Updated to .debug_.* with the
	SHF_COMPRESSED bit.
	* ld-elf/zlibnormal.rS: Likewise.

1 files changed, 9 insertions, 7 deletions

diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
index 0781036..466f125 100644
--- a/binutils/doc/binutils.texi
+++ b/binutils/doc/binutils.texi
@@ -1844,10 +1844,9 @@ It can also be a useful way of reducing the size of a @option{--just-symbols}
 linker input file.
 
 @item --compress-debug-sections
-Compress DWARF debug sections using zlib.  The debug sections are
-renamed to begin with @samp{.zdebug} instead of @samp{.debug}.  Note -
-if compression would actually make a section @emph{larger} then it is
-not compressed or renamed.
+Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
+ELF ABI.  Note - if compression would actually make a section
+@emph{larger}, then it is not compressed.
 
 @item --compress-debug-sections=none
 @itemx --compress-debug-sections=zlib
@@ -1857,10 +1856,13 @@ For ELF files, these options control how DWARF debug sections are
 compressed.  @option{--compress-debug-sections=none} is equivalent
 to @option{--nocompress-debug-sections}.
 @option{--compress-debug-sections=zlib} and
-@option{--compress-debug-sections=zlib-gnu} are equivalent to
+@option{--compress-debug-sections=zlib-gabi} are equivalent to
 @option{--compress-debug-sections}.
-@option{--compress-debug-sections=zlib-gabi} compresses
-DWARF debug sections with SHF_COMPRESSED from the ELF ABI.
+@option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
+sections using zlib.  The debug sections are renamed to begin with
+@samp{.zdebug} instead of @samp{.debug}.  Note - if compression would
+actually make a section @emph{larger}, then it is not compressed nor
+renamed.
 
 @item --decompress-debug-sections
 Decompress DWARF debug sections using zlib.  The original section