binutils-gdb/ld/testsuite/ld-elf/retain2.ld

SECTIONS
{
  /DISCARD/ :
  {
    *(.text.fnretain1)
  }
}
Support SHF_GNU_RETAIN ELF section flag The SHF_GNU_RETAIN section flag is an extension to the GNU ELF OSABI. It is defined as follows: ========================================================= Section Attribute Flags +-------------------------------------+ \| Name \| Value \| +-------------------------------------+ \| SHF_GNU_RETAIN \| 0x200000 (1 << 21) \| +-------------------------------------+ SHF_GNU_RETAIN The link editor should not garbage collect the section. ========================================================= The .section directive accepts the "R" flag, which indicates SHF_GNU_RETAIN should be applied to the section. There is not a direct mapping of SHF_GNU_RETAIN to the BFD section flag SEC_KEEP. Keeping these flags distinct allows SHF_GNU_RETAIN sections to be explicitly removed by placing them in /DISCARD/. bfd/ChangeLog: * elf-bfd.h (enum elf_gnu_osabi): Add elf_gnu_osabi_retain. (struct elf_obj_tdata): Increase has_gnu_osabi to 4 bits. * elf.c (_bfd_elf_make_section_from_shdr): Set elf_gnu_osabi_retain for SHF_GNU_RETAIN. (_bfd_elf_final_write_processing): Report if SHF_GNU_RETAIN is not supported by the OSABI. Adjust error messages. * elflink.c (elf_link_input_bfd): Copy enabled has_gnu_osabi bits from input BFD to output BFD. (bfd_elf_gc_sections): gc_mark the section if SHF_GNU_RETAIN is set. binutils/ChangeLog: * NEWS: Announce SHF_GNU_RETAIN support. * readelf.c (get_elf_section_flags): Handle SHF_GNU_RETAIN. Recognize SHF_GNU_RETAIN and SHF_GNU_MBIND only for supported OSABIs. * testsuite/binutils-all/readelf.exp: Run new tests. Don't run run_dump_test when there isn't an assembler available. * testsuite/lib/binutils-common.exp (supports_gnu_osabi): Adjust comment. * testsuite/binutils-all/readelf-maskos-1a.d: New test. * testsuite/binutils-all/readelf-maskos-1b.d: New test. * testsuite/binutils-all/readelf-maskos.s: New test. * testsuite/binutils-all/retain1.s: New test. * testsuite/binutils-all/retain1a.d: New test. * testsuite/binutils-all/retain1b.d: New test. gas/ChangeLog: * NEWS: Announce SHF_GNU_RETAIN support. * config/obj-elf.c (obj_elf_change_section): Merge SHF_GNU_RETAIN bit between section declarations. (obj_elf_parse_section_letters): Handle 'R' flag. Handle numeric flag values within the SHF_MASKOS range. (obj_elf_section): Validate SHF_GNU_RETAIN usage. * doc/as.texi: Document 'R' flag to .section directive. * testsuite/gas/elf/elf.exp: Run new tests. * testsuite/gas/elf/section10.d: Unset SHF_GNU_RETAIN bit. * testsuite/gas/elf/section10.s: Likewise. * testsuite/gas/elf/section22.d: New test. * testsuite/gas/elf/section22.s: New test. * testsuite/gas/elf/section23.s: New test. * testsuite/gas/elf/section23a.d: New test. * testsuite/gas/elf/section23b.d: New test. * testsuite/gas/elf/section23b.err: New test. * testsuite/gas/elf/section24.l: New test. * testsuite/gas/elf/section24.s: New test. * testsuite/gas/elf/section24a.d: New test. * testsuite/gas/elf/section24b.d: New test. include/ChangeLog: * elf/common.h (SHF_GNU_RETAIN): Define. ld/ChangeLog: * NEWS: Announce support for SHF_GNU_RETAIN. * ld.texi (garbage collection): Document SHF_GNU_RETAIN. (Output Section Discarding): Likewise. * testsuite/ld-elf/elf.exp: Run new tests. * testsuite/ld-elf/retain1.s: New test. * testsuite/ld-elf/retain1a.d: New test. * testsuite/ld-elf/retain1b.d: New test. * testsuite/ld-elf/retain2.d: New test. * testsuite/ld-elf/retain2.ld: New test. * testsuite/ld-elf/retain2.map: New test. * testsuite/ld-elf/retain3.d: New test. * testsuite/ld-elf/retain3.s: New test. * testsuite/ld-elf/retain4.d: New test. * testsuite/ld-elf/retain4.s: New test. * testsuite/ld-elf/retain5.d: New test. * testsuite/ld-elf/retain5.map: New test. * testsuite/ld-elf/retain5lib.s: New test. * testsuite/ld-elf/retain5main.s: New test. * testsuite/ld-elf/retain6a.d: New test. * testsuite/ld-elf/retain6b.d: New test. * testsuite/ld-elf/retain6lib.s: New test. * testsuite/ld-elf/retain6main.s: New test. 2020-11-18 19:51:13 +08:00			`SECTIONS`
			`{`
			`/DISCARD/ :`
			`{`
			`*(.text.fnretain1)`
			`}`
			`}`