binutils-gdb/ld
H.J. Lu 0aa99dcd70 Use GCC LTO wrapper to get real symbols from LTO IR objects
GCC LTO wrapper is needed to extract real symbols from LTO IR objects.
This patch does the following:

1. Set up GCC LTO wrapper for each LTO IR object.
2. Run GCC LTO wrapper to get the real object.
3. Extract symbol info from the real object.
4. Cleanup afterwards.

bfd/

	PR binutils/25355
	* configure.ac (HAVE_EXECUTABLE_SUFFIX): New AC_DEFINE.
	(EXECUTABLE_SUFFIX): Likewise.
	* config.in: Regenerated.
	* configure: Likewise.
	* plugin.c (bfd_plugin_close_and_cleanup): Removed.
	(plugin_list_entry): Add all_symbols_read, cleanup_handler,
	gcc, lto_wrapper, resolution_file, resolution_option, gcc_env,
	real_bfd, real_nsyms, real_syms, lto_nsyms and lto_syms.
	(get_lto_wrapper): New.
	(setup_lto_wrapper_env): Likewise.
	(current_plugin): Likewise.
	(register_all_symbols_read): Likewise.
	(register_cleanup): Likewise.
	(get_symbols): Likewise.
	(add_input_file): Likewise.
	(bfd_plugin_close_and_cleanup): Likewise.
	(claim_file): Removed.
	(register_claim_file): Set current_plugin->claim_file.
	(add_symbols): Make a copy of LTO symbols.  Set lto_nsyms and
	lto_syms in current_plugin.
	(try_claim): Use current_plugin->claim_file.  Call LTO plugin
	all_symbols_read handler.  Copy real symbols to plugin_data.
	Call LTO plugin cleanup handler.  Clean up for LTO wrapper.
	(try_load_plugin): Don't reuse the previous plugin for LTO
	wrapper.  Set up GCC LTO wrapper if possible.  Don't set
	plugin_list_iter->claim_file.
	(bfd_plugin_canonicalize_symtab): Use real LTO symbols if
	possible.
	* plugin.h (plugin_data_struct): Add real_bfd, real_nsyms and
	real_syms.

ld/

	PR binutils/25355
	* testsuite/ld-plugin/lto.exp: Run PR binutils/25355 test.
	* testsuite/ld-plugin/pr25355.c: New file.
	* testsuite/ld-plugin/pr25355.d: Likewise.
	* testsuite/lib/ld-lib.exp (run_cc_link_tests): Support compile
	only dump.
2020-02-10 19:01:53 -08:00
..
emulparams
emultempl
po
scripttempl
testsuite
.gitignore
aclocal.m4
ChangeLog
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-2014
ChangeLog-2015
ChangeLog-2016
ChangeLog-2017
ChangeLog-2018
ChangeLog-2019
ChangeLog-9197
ChangeLog-9899
config.in
configure
configure.ac
configure.host
configure.tgt
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.texi
ldbuildid.c
ldbuildid.h
ldcref.c
ldctor.c
ldctor.h
ldelf.c
ldelf.h
ldelfgen.c
ldelfgen.h
ldemul.c
ldemul.h
ldexp.c
ldexp.h
ldfile.c
ldfile.h
ldgram.y
ldint.texi
ldlang.c
ldlang.h
ldlex-wrapper.c
ldlex.h
ldlex.l
ldmain.c
ldmain.h
ldmisc.c
ldmisc.h
ldver.c
ldver.h
ldwrite.c
ldwrite.h
lexsup.c
MAINTAINERS
Makefile.am
Makefile.in
mri.c
mri.h
NEWS
pe-dll.c
pe-dll.h
pep-dll.c
pep-dll.h
plugin.c
plugin.h
README
stamp-h.in
sysdep.h
testplug2.c
testplug3.c
testplug4.c
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.texi), as well as the
  beginnings of an internals manual (ldint.texi).

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