From 8ee10e86093150c70360d9e26b29e6d9b6398f33 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Mon, 1 Mar 2021 08:22:49 +1030 Subject: 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. --- include/ChangeLog | 5 +++++ include/bfdlink.h | 4 ++++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/ChangeLog b/include/ChangeLog index 616b923..16c14d9 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,8 @@ +2021-03-01 Alan Modra + Fangrui Song + + * bfdlink.h (struct bfd_link_info): Add start_stop_gc. + 2021-02-21 Alan Modra * bfdlink.h (struct bfd_link_info): Add warn_multiple_definition. diff --git a/include/bfdlink.h b/include/bfdlink.h index 95728b6..0871a0c 100644 --- a/include/bfdlink.h +++ b/include/bfdlink.h @@ -662,6 +662,10 @@ struct bfd_link_info /* May be used to set DT_GNU_FLAGS_1 for ELF. */ bfd_vma gnu_flags_1; + /* TRUE if references to __start_/__stop_ synthesized symbols do not + specially retain C identifier named sections. */ + int start_stop_gc; + /* May be used to set ELF visibility for __start_* / __stop_. */ unsigned int start_stop_visibility; -- cgit v1.1