PR27451, -z start_stop_gc
authorAlan Modra <amodra@gmail.com>
Sun, 28 Feb 2021 21:52:49 +0000 (08:22 +1030)
committerAlan Modra <amodra@gmail.com>
Mon, 1 Mar 2021 06:58:03 +0000 (17:28 +1030)
commit8ee10e86093150c70360d9e26b29e6d9b6398f33
treed9b022e21486a83064279ec452009a394b62a8b0
parent7824c1d22fcab8a68162634d4293f4a6666ca43e
PR27451, -z start_stop_gc

When --gc-sections is in effect, a reference from a retained section
to __start_SECNAME or __stop_SECNAME causes all input sections named
SECNAME to also be retained, if SECNAME is representable as a C
identifier and either __start_SECNAME or __stop_SECNAME is synthesized
by the linker.  Add an option to disable that feature, effectively
ignoring any relocation that references a synthesized linker defined
__start_ or __stop_ symbol.

PR 27451
include/
* bfdlink.h (struct bfd_link_info): Add start_stop_gc.
bfd/
* elflink.c (_bfd_elf_gc_mark_rsec): Ignore synthesized linker
defined start/stop symbols when start_stop_gc.
(bfd_elf_gc_mark_dynamic_ref_symbol): Likewise.
(bfd_elf_define_start_stop): Don't modify ldscript_def syms.
* linker.c (bfd_generic_define_start_stop): Likewise.
ld/
* emultempl/elf.em: Handle -z start-stop-gc and -z nostart-stop-gc.
* lexsup.c (elf_static_list_options): Display help for them.  Move
help for -z stack-size to here from elf_shlib_list_options. Add
help for -z start-stop-visibility and -z undefs.
* ld.texi: Document -z start-stop-gc and -z nostart-stop-gc.
* NEWS: Mention -z start-stop-gc.
* testsuite/ld-gc/start2.s,
* testsuite/ld-gc/start2.d: New test.
* testsuite/ld-gc/gc.exp: Run it.
14 files changed:
bfd/ChangeLog
bfd/elflink.c
bfd/linker.c
include/ChangeLog
include/bfdlink.h
ld/ChangeLog
ld/NEWS
ld/emultempl/elf.em
ld/ld.texi
ld/ldmain.c
ld/lexsup.c
ld/testsuite/ld-gc/gc.exp
ld/testsuite/ld-gc/start2.d [new file with mode: 0644]
ld/testsuite/ld-gc/start2.s [new file with mode: 0644]