binutils-gdb/ld/testsuite/ld-elf/pr21562b.t

SECTIONS {
	PROVIDE (__start_scnfoo = .);
	scnfoo : { *(scnfoo) }
	PROVIDE (__stop_scnfoo = .);
}
Always define referenced __start_SECNAME/__stop_SECNAME Currently, linker will define __start_SECNAME and __stop_SECNAME symbols only for orphaned sections. However, during garbage collection, ELF linker marks all sections with references to __start_SECNAME and __stop_SECNAME symbols as used even when section SECNAME isn't an orphaned section and linker won't define __start_SECNAME nor __stop_SECNAME. And ELF linker stores the first input section whose name matches __start_SECNAME or __stop_SECNAME in u.undef.section for garbage collection. If these symbols are provided in linker script, u.undef.section is set to the section where they will defined by linker script, which leads to the incorrect output. This patch changes linker to always define referenced __start_SECNAME and __stop_SECNAME if the input section name is the same as the output section name, which is always true for orphaned sections, and SECNAME is a C identifier. Also __start_SECNAME and __stop_SECNAME symbols are marked as hidden by ELF linker so that __start_SECNAME and __stop_SECNAME symbols for section SECNAME in different modules are unique. For garbage collection, ELF linker stores the first matched input section in the unused vtable field. bfd/ PR ld/20022 PR ld/21557 PR ld/21562 PR ld/21571 * elf-bfd.h (elf_link_hash_entry): Add start_stop. Change the vtable field to a union. (_bfd_elf_is_start_stop): Removed. * elf32-i386.c (elf_i386_convert_load_reloc): Also check for __start_SECNAME and __stop_SECNAME symbols. * elf64-x86-64.c (elf_x86_64_convert_load_reloc): Likewise. * elflink.c (_bfd_elf_is_start_stop): Removed. (_bfd_elf_gc_mark_rsec): Check start_stop instead of calling _bfd_elf_is_start_stop. (elf_gc_propagate_vtable_entries_used): Skip __start_SECNAME and __stop_SECNAME symbols. Updated. (elf_gc_smash_unused_vtentry_relocs): Likewise. (bfd_elf_gc_record_vtinherit): Likewise. (bfd_elf_gc_record_vtentry): Likewise. ld/ PR ld/20022 PR ld/21557 PR ld/21562 PR ld/21571 * ld.texinfo: Update __start_SECNAME/__stop_SECNAME symbols. * ldlang.c (lang_insert_orphan): Move handling of __start_SECNAME and __stop_SECNAME symbols to ... (lang_set_startof): Here. Also define __start_SECNAME and __stop_SECNAME for -Ur. * emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Mark referenced __start_SECNAME and __stop_SECNAME symbols as hidden and set start_stop for garbage collection. * testsuite/ld-elf/pr21562a.d: New file. * testsuite/ld-elf/pr21562a.s: Likewise. * testsuite/ld-elf/pr21562a.t: Likewise. * testsuite/ld-elf/pr21562b.d: Likewise. * testsuite/ld-elf/pr21562b.s: Likewise. * testsuite/ld-elf/pr21562b.t: Likewise. * testsuite/ld-elf/pr21562c.d: Likewise. * testsuite/ld-elf/pr21562c.t: Likewise. * testsuite/ld-elf/pr21562d.d: Likewise. * testsuite/ld-elf/pr21562d.t: Likewise. * testsuite/ld-elf/pr21562e.d: Likewise. * testsuite/ld-elf/pr21562f.d: Likewise. * testsuite/ld-elf/pr21562g.d: Likewise. * testsuite/ld-elf/pr21562h.d: Likewise. * testsuite/ld-elf/pr21562i.d: Likewise. * testsuite/ld-elf/pr21562j.d: Likewise. * testsuite/ld-elf/pr21562k.d: Likewise. * testsuite/ld-elf/pr21562l.d: Likewise. * testsuite/ld-elf/pr21562m.d: Likewise. * testsuite/ld-elf/pr21562n.d: Likewise. * testsuite/ld-gc/pr20022.d: Likewise. * testsuite/ld-gc/pr20022a.s: Likewise. * testsuite/ld-gc/pr20022b.s: Likewise. * testsuite/ld-gc/gc.exp: Run PR ld/20022 tests. * testsuite/ld-gc/pr19161.d: Also accept local __start_SECNAME symbol. * testsuite/ld-gc/start.d: Likewise. * testsuite/ld-x86-64/lea1a.d: Updated. * testsuite/ld-x86-64/lea1b.d: Updated. * testsuite/ld-x86-64/lea1d.d: Updated. * testsuite/ld-x86-64/lea1e.d: Likewise. 2017-06-13 23:53:22 +08:00			`SECTIONS {`
			`PROVIDE (__start_scnfoo = .);`
			`scnfoo : { *(scnfoo) }`
			`PROVIDE (__stop_scnfoo = .);`
			`}`