binutils-gdb/ld
Andrew Burgess edc9e9a62f AVR: Assembler now prepares for linker relaxation by default.
Have the assembler prepare for linker relaxation by default.  This
means that users will be able to make use of linker relaxation without
having to adjust the assembler flags, this can make life easier when
compiling libraries.

Having this on by default in the assembler should make no difference to
the assembler code produced, however, some of the debug information will
be slightly less compressed.

A few tests needed to be updated as a result of this change as they
relied on linker relaxation support being off by default.

I've tightened up the definition of which sections can be relaxed on AVR
as part of this commit, the assembler used to think that all
non-debugging sections could be relaxed, when in reality only code
sections can be relaxed for AVR.  The previous definition was not
dangerous, just over cautious.  The new tighter definition allows an
extra test (gas/testsuite/gas/all/forward.d) to continue to pass.

gas/ChangeLog:

	* config/tc-avr.c (struct avr_opt_s): Change link_relax to
	no_link_relax, extend comment.
	(enum options): Add new OPTION_NO_LINK_RELAX.
	(md_longopts): Add entry for -mno-link-relax.
	(md_parse_option): Handle OPTION_NO_LINK_RELAX, and update
	OPTION_LINK_RELAX.
	(md_begin): Initialise linkrelax from no_link_relax.
	(md_show_usage): Include -mno-link-relax option.
	(relaxable_section): Only allocatable code sections can be
	relaxed.
	* config/tc-avr.h (TC_LINKRELAX_FIXUP): Define.

gas/testsuite/ChangeLog:

	* gas/all/gas.exp: Test will not pass on AVR due to linker
	relaxation support.
	* gas/avr/noreloc_withoutrelax.d: Add -mno-link-relax option.
	* gas/avr/link-relax-elf-flag-clear.d: Likewise.

ld/testsuite/ChangeLog:

	* ld/testsuite/ld-avr/relax-elf-flags-02.d: Add -mno-link-relax
	option.
	* ld/testsuite/ld-avr/relax-elf-flags-03.d: Likewise.
	* ld/testsuite/ld-avr/relax-elf-flags-04.d: Likewise.
	* ld/testsuite/ld-avr/relax-elf-flags-05.d: Likewise.
	* ld/testsuite/ld-avr/relax-elf-flags-06.d: Likewise.
2014-12-24 21:27:43 +00:00
..
emulparams Add Visium support to ld 2014-12-06 16:45:22 +01:00
emultempl Don't create .eh_frame_hdr on shared lib bfd 2014-12-24 23:47:56 +10:30
po Updated/new translations provided by the Translations Project. 2014-10-29 16:34:04 +00:00
scripttempl Add Visium support to ld 2014-12-06 16:45:22 +01:00
testsuite AVR: Assembler now prepares for linker relaxation by default. 2014-12-24 21:27:43 +00:00
.gitignore
aclocal.m4
ChangeLog Don't create .eh_frame_hdr on shared lib bfd 2014-12-24 23:47:56 +10:30
ChangeLog-0001
ChangeLog-0203
ChangeLog-2004
ChangeLog-2005
ChangeLog-2006
ChangeLog-2007
ChangeLog-2008
ChangeLog-2009
ChangeLog-2010
ChangeLog-2011
ChangeLog-2012
ChangeLog-2013
ChangeLog-9197
ChangeLog-9899
config.in
configure Update libtool.m4 from GCC trunk 2014-11-24 09:14:09 -08:00
configure.ac
configure.host
configure.tgt Add Visium support to ld 2014-12-06 16:45:22 +01:00
deffile.h
deffilep.y
dep-in.sed
elf-hints-local.h
fdl.texi
gen-doc.texi
genscrba.sh
genscripts.sh
h8-doc.texi
ld.h
ld.texinfo PowerPC64 --plt-align 2014-11-24 12:56:59 +10:30
ldbuildid.c
ldbuildid.h
ldcref.c
ldctor.c
ldctor.h
ldemul.c
ldemul.h
ldexp.c Report an error for script multiply defined symbols 2014-12-23 23:36:51 +10:30
ldexp.h Move support code for linker script DEFINED to ldexp.c 2014-12-23 23:36:50 +10:30
ldfile.c
ldfile.h
ldgram.y Allow unquoted = as the first character in ldscript input_list names 2014-10-15 03:10:25 +02:00
ldint.texinfo
ldlang.c Move support code for linker script DEFINED to ldexp.c 2014-12-23 23:36:50 +10:30
ldlang.h Move support code for linker script DEFINED to ldexp.c 2014-12-23 23:36:50 +10:30
ldlex-wrapper.c
ldlex.h Implement --print-sysroot in ld. 2014-10-17 13:06:56 +02:00
ldlex.l Allow unquoted = as the first character in ldscript input_list names 2014-10-15 03:10:25 +02:00
ldmain.c Move support code for linker script DEFINED to ldexp.c 2014-12-23 23:36:50 +10:30
ldmain.h
ldmisc.c Don't always build coffgen.o 2014-12-10 23:13:49 +10:30
ldmisc.h
ldver.c
ldver.h
ldwrite.c
ldwrite.h
lexsup.c Implement --print-sysroot in ld. 2014-10-17 13:06:56 +02:00
MAINTAINERS
Makefile.am Add Visium support to ld 2014-12-06 16:45:22 +01:00
Makefile.in Add Visium support to ld 2014-12-06 16:45:22 +01:00
mri.c
mri.h
NEWS Add NEWS markers for 2.25. 2014-10-14 09:49:47 +02:00
pe-dll.c
pe-dll.h
pep-dll.c
pep-dll.h
plugin.c
plugin.h
README
stamp-h.in
sysdep.h
testplug.c
TODO

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		README for LD

This is the GNU linker.  It is distributed with other "binary
utilities" which should be in ../binutils.  See ../binutils/README for
more general notes, including where to send bug reports.

There are many features of the linker:

* The linker uses a Binary File Descriptor library (../bfd)
  that it uses to read and write object files.  This helps
  insulate the linker itself from the format of object files.

* The linker supports a number of different object file
  formats.  It can even handle multiple formats at once:
  Read two input formats and write a third.

* The linker can be configured for cross-linking.

* The linker supports a control language.

* There is a user manual (ld.texinfo), as well as the
  beginnings of an internals manual (ldint.texinfo).

Installation
============

See ../binutils/README.

If you want to make a cross-linker, you may want to specify
a different search path of -lfoo libraries than the default.
You can do this by setting the LIB_PATH variable in ./Makefile
or using the --with-lib-path configure switch.

To build just the linker, make the target all-ld from the top level
directory (one directory above this one).

Porting to a new target
=======================

See the ldint.texinfo manual.

Reporting bugs etc
===========================

See ../binutils/README.

Known problems
==============

The Solaris linker normally exports all dynamic symbols from an
executable.  The GNU linker does not do this by default.  This is
because the GNU linker tries to present the same interface for all
similar targets (in this case, all native ELF targets).  This does not
matter for normal programs, but it can make a difference for programs
which try to dlopen an executable, such as PERL or Tcl.  You can make
the GNU linker export all dynamic symbols with the -E or
--export-dynamic command line option.

HP/UX 9.01 has a shell bug that causes the linker scripts to be
generated incorrectly.  The symptom of this appears to be "fatal error
- scanner input buffer overflow" error messages.  There are various
workarounds to this:
  * Build and install bash, and build with "make SHELL=bash".
  * Update to a version of HP/UX with a working shell (e.g., 9.05).
  * Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
    genscripts.sh with "sh ${srcdir}..." (no parens) and make sure the
    emulparams script used exports any shell variables it sets.

Copyright (C) 2012-2014 Free Software Foundation, Inc.

Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
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