forked from Imagelibrary/binutils-gdb
b21318bd2c
This is one part of the fix for GCC PR109128, along with a corresponding GCC change. Without this patch, what happens in the linker, when an unused object in a .a file has offload data, is that elf_link_is_defined_archive_symbol calls bfd_link_plugin_object_p, which ends up calling the plugin's claim_file_handler, which then records the object as one with offload data. That is, the linker never decides to use the object in the first place, but use of this _p interface (called as part of trying to decide whether to use the object) results in the plugin deciding to use its offload data (and a consequent mismatch in the offload data present at runtime). The new hook allows the linker plugin to distinguish calls to claim_file_handler that know the object is being used by the linker (from ldmain.c:add_archive_element), from calls that don't know it's being used by the linker (from elf_link_is_defined_archive_symbol); in the latter case, the plugin should avoid recording the object as one with offload data. bfd/ * plugin.c (struct plugin_list_entry): Add claim_file_v2. (register_claim_file_v2): New. (try_load_plugin): Use LDPT_REGISTER_CLAIM_FILE_HOOK_V2. (ld_plugin_object_p): Take second argument. (bfd_link_plugin_object_p): Update call to ld_plugin_object_p. (register_ld_plugin_object_p): Update argument prototype. (bfd_plugin_object_p): Update call to ld_plugin_object_p. * plugin.h (register_ld_plugin_object_p): Update argument prototype. include/ * plugin.api.h (ld_plugin_claim_file_handler_v2) (ld_plugin_register_claim_file_v2) (LDPT_REGISTER_CLAIM_FILE_HOOK_V2): New. (struct ld_plugin_tv): Add tv_register_claim_file_v2. ld/ * plugin.c (struct plugin): Add claim_file_handler_v2. (LDPT_REGISTER_CLAIM_FILE_HOOK_V2): New. (plugin_object_p): Add second argument. Update call to plugin_call_claim_file. (register_claim_file_v2): New. (set_tv_header): Handle LDPT_REGISTER_CLAIM_FILE_HOOK_V2. (plugin_call_claim_file): Add argument known_used. (plugin_maybe_claim): Update call to plugin_object_p. * testplug.c, testplug2.c, testplug3.c, testplug4.c: Handle LDPT_REGISTER_CLAIM_FILE_HOOK_V2. * testsuite/ld-plugin/plugin-1.d, testsuite/ld-plugin/plugin-10.d, testsuite/ld-plugin/plugin-11.d, testsuite/ld-plugin/plugin-13.d, testsuite/ld-plugin/plugin-14.d, testsuite/ld-plugin/plugin-15.d, testsuite/ld-plugin/plugin-16.d, testsuite/ld-plugin/plugin-17.d, testsuite/ld-plugin/plugin-18.d, testsuite/ld-plugin/plugin-19.d, testsuite/ld-plugin/plugin-2.d, testsuite/ld-plugin/plugin-26.d, testsuite/ld-plugin/plugin-3.d, testsuite/ld-plugin/plugin-30.d, testsuite/ld-plugin/plugin-4.d, testsuite/ld-plugin/plugin-5.d, testsuite/ld-plugin/plugin-6.d, testsuite/ld-plugin/plugin-7.d, testsuite/ld-plugin/plugin-8.d, testsuite/ld-plugin/plugin-9.d: Update test expectations.
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.
Copyright (C) 2012-2023 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.