and other tidies. I think it's better to default to passing the
section to bfd_octets_per_byte, even in cases where we know it won't
make a difference.
A number of the coff reloc functions used bfd_octets_per_byte wrongly,
not factoring it into the offset into the data buffer. As it happens,
the targets using those files always had bfd_octets_per_byte equal to
one, so there wasn't any detectable wrong behaviour. However, it is
wrong in the source and might cause trouble for anyone creating a new
target. Besides fixing that, the patch also defines OCTETS_PER_BYTE
as one in target files where that is appropriate.
bfd/
* archures.c (bfd_octets_per_byte): Tail call
bfd_arch_mach_octets_per_byte.
* coff-arm.c (OCTETS_PER_BYTE): Define.
(coff_arm_reloc): Introduce new "octets" temp. Use OCTETS_PER_BYTE
with section. Correct "addr". Remove ATTRIBUTE_UNUSED.
* coff-i386.c (coff_i386_reloc): Similarly.
* coff-mips.c (mips_reflo_reloc): Similarly.
* coff-x86_64.c (coff_amd64_reloc): Similarly.
* elf32-msp430.c (OCTETS_PER_BYTE): Define.
(rl78_sym_diff_handler): Use OCTETS_PER_BYTE, with section.
* elf32-nds32.c (nds32_elf_get_relocated_section_contents): Similarly.
* elf32-ppc.c (ppc_elf_addr16_ha_reloc): Similarly.
* elf32-pru.c (pru_elf32_do_ldi32_relocate): Similarly.
* elf32-s12z.c (opru18_reloc): Similarly.
* elf32-sh.c (sh_elf_reloc): Similarly.
* elf32-spu.c (spu_elf_rel9): Similarly.
* elf32-xtensa.c (bfd_elf_xtensa_reloc): Similarly.
* elf64-ppc.c (ppc64_elf_ha_reloc, ppc64_elf_brtaken_reloc),
(ppc64_elf_toc64_reloc): Similarly.
* bfd.c (bfd_get_section_limit): Pass section to bfd_octets_per_byte.
* cofflink.c (_bfd_coff_link_input_bfd),
(_bfd_coff_reloc_link_order): Likewise.
* elf.c (_bfd_elf_section_offset): Likewise.
* elflink.c (resolve_section, bfd_elf_perform_complex_relocation),
(elf_link_input_bfd, elf_reloc_link_order, elf_fixup_link_order),
(bfd_elf_final_link): Likewise.
* elf.c (_bfd_elf_make_section_from_shdr): Don't strncmp twice
to set SEC_ELF_OCTETS.
* reloc.c (bfd_perform_relocation): Tidy SEC_ELF_OCTETS special case.
(bfd_install_relocation): Likewise.
(_bfd_final_link_relocate): Don't recalculate octets.
* syms.c (_bfd_stab_section_find_nearest_line): Introduc new
"octets" temp.
* bfd-in2.h: Regenerate.
ld/
* ldexp.c (fold_name): Pass section to bfd_octets_per_byte.
* ldlang.c (init_opb): Don't call bfd_arch_mach_octets_per_byte
unnecessarily.
All symbols, sizes and relocations in this section are octets instead of
bytes. Required for DWARF debug sections as DWARF information is
organized in octets, not bytes.
bfd/
* section.c (struct bfd_section): New flag SEC_ELF_OCTETS.
* archures.c (bfd_octets_per_byte): New parameter sec.
If section is not NULL and SEC_ELF_OCTETS is set, one octet es
returned [ELF targets only].
* bfd.c (bfd_get_section_limit): Provide section parameter to
bfd_octets_per_byte.
* bfd-in2.h: regenerate.
* binary.c (binary_set_section_contents): Move call to
bfd_octets_per_byte into section loop. Provide section parameter
to bfd_octets_per_byte.
* coff-arm.c (coff_arm_reloc): Provide section parameter
to bfd_octets_per_byte.
* coff-i386.c (coff_i386_reloc): likewise.
* coff-mips.c (mips_reflo_reloc): likewise.
* coff-x86_64.c (coff_amd64_reloc): likewise.
* cofflink.c (_bfd_coff_link_input_bfd): likewise.
(_bfd_coff_reloc_link_order): likewise.
* elf.c (_bfd_elf_section_offset): likewise.
(_bfd_elf_make_section_from_shdr): likewise.
Set SEC_ELF_OCTETS for sections with names .gnu.build.attributes,
.debug*, .zdebug* and .note.gnu*.
* elf32-msp430.c (rl78_sym_diff_handler): Provide section parameter
to bfd_octets_per_byte.
* elf32-nds.c (nds32_elf_get_relocated_section_contents): likewise.
* elf32-ppc.c (ppc_elf_addr16_ha_reloc): likewise.
* elf32-pru.c (pru_elf32_do_ldi32_relocate): likewise.
* elf32-s12z.c (opru18_reloc): likewise.
* elf32-sh.c (sh_elf_reloc): likewise.
* elf32-spu.c (spu_elf_rel9): likewise.
* elf32-xtensa.c (bfd_elf_xtensa_reloc): likewise
* elf64-ppc.c (ppc64_elf_brtaken_reloc): likewise.
(ppc64_elf_addr16_ha_reloc): likewise.
(ppc64_elf_toc64_reloc): likewise.
* elflink.c (bfd_elf_final_link): likewise.
(bfd_elf_perform_complex_relocation): likewise.
(elf_fixup_link_order): likewise.
(elf_link_input_bfd): likewise.
(elf_link_sort_relocs): likewise.
(elf_reloc_link_order): likewise.
(resolve_section): likewise.
* linker.c (_bfd_generic_reloc_link_order): likewise.
(bfd_generic_define_common_symbol): likewise.
(default_data_link_order): likewise.
(default_indirect_link_order): likewise.
* srec.c (srec_set_section_contents): likewise.
(srec_write_section): likewise.
* syms.c (_bfd_stab_section_find_nearest_line): likewise.
* reloc.c (_bfd_final_link_relocate): likewise.
(bfd_generic_get_relocated_section_contents): likewise.
(bfd_install_relocation): likewise.
For section which have SEC_ELF_OCTETS set, multiply output_base
and output_offset with bfd_octets_per_byte.
(bfd_perform_relocation): likewise.
include/
* coff/ti.h (GET_SCNHDR_SIZE, PUT_SCNHDR_SIZE, GET_SCN_SCNLEN),
(PUT_SCN_SCNLEN): Adjust bfd_octets_per_byte calls.
binutils/
* objdump.c (disassemble_data): Provide section parameter to
bfd_octets_per_byte.
(dump_section): likewise
(dump_section_header): likewise. Show SEC_ELF_OCTETS flag if set.
gas/
* as.h: Define SEC_OCTETS as SEC_ELF_OCTETS if OBJ_ELF.
* dwarf2dbg.c: (dwarf2_finish): Set section flag SEC_OCTETS for
.debug_line, .debug_info, .debug_abbrev, .debug_aranges, .debug_str
and .debug_ranges sections.
* write.c (maybe_generate_build_notes): Set section flag
SEC_OCTETS for .gnu.build.attributes section.
* frags.c (frag_now_fix): Don't divide by OCTETS_PER_BYTE if
SEC_OCTETS is set.
* symbols.c (resolve_symbol_value): Likewise.
ld/
* ldexp.c (fold_name): Provide section parameter to
bfd_octets_per_byte.
* ldlang (init_opb): New argument s. Set opb_shift to 0 if
SEC_ELF_OCTETS for the current section is set.
(print_input_section): Pass current section to init_opb.
(print_data_statement,print_reloc_statement,
print_padding_statement): Likewise.
(lang_check_section_addresses): Call init_opb for each
section.
(lang_size_sections_1,lang_size_sections_1,
lang_do_assignments_1): Likewise.
(lang_process): Pass NULL to init_opb.
This particular sort almost certainly does not need to be stable for
the ELF linker to work correctly. However it is conceivable that an
unstable sort could affect linker output, and thus different output be
seen with differing qsort implementations. The argument goes like
this: Given more than one strong alias symbol of equal section, value,
and size, the aliases will compare equal by elf_sort_symbol and thus
which one is chosen as the "real" symbol to be made dynamic depends on
qsort. Why would anyone define two symbols at the same address?
Well, sometimes the fact that there are more than one strong alias
symbol is due to linker script symbols like __bss_start being made
dynamic. This will match the first symbol defined in .bss if it
doesn't have correct size, and forgetting to properly set size and
type of symbols isn't as rare as it should be.
This patch adds some more heuristics to elf_sort_symbol.
* elflink.c (elf_sort_symbol): Sort on type and name as well.
(elf_link_add_object_symbols): Style fix.
elf_sort_sections tried to ensure a stable qsort by using target_index
as the final comparison, but target_index hasn't been set by anything
at the time elf_sort_sections was run. This patch arrange to have
target_index set.
* elf.c (_bfd_elf_map_sections_to_segments): Init target_index
for sections about to be sorted.
(assign_file_positions_for_load_sections): Likewise.
(elf_sort_sections): Don't bother optimising both TOEND case.
* elflink.c (bfd_elf_final_link): Reset target_index.
The linker SHF_LINK_ORDER section sorting had a number of defects.
1) The ordering was by VMA, which won't work with overlays. LMA is
better.
2) Zero size sections can result in two sections at the same LMA/VMA.
When only one of the two sections at the same LMA is zero size,
that one must be first.
3) Warnings given by elf_get_linked_section_vma won't ever be emitted
since elf_object_p warns and excludes objects with zero sh_link on
a SHF_LINK_ORDER section.
4) Section offset was adjusted down rather than up by section
alignment, possibly creating overlapping sections.
5) Finding the linked section did so the hard way, rather than simply
using elf_linked_to_section.
* elflink.c (elf_get_linked_section_vma): Delete.
(compare_link_order): Use elf_linked_to_section and sort by lma,
size, and id.
(elf_fixup_link_order): Use size_t variables where appropriate.
Make use of elf_linked_to_section. Formatting. Properly align
sections.
qsort isn't guaranteed to be a stable sort, that is, elements
comparing equal according to the comparison function may be reordered
relative to their original ordering. Of course sometimes you may not
care, but even in those cases it is good to force some ordering
(ie. not have the comparison function return 0) so that linker output
is reproducible over different libc qsort implementations.
One way to make qsort stable (which the glibc manual incorrectly says
is the only way) is to augment the elements being sorted with a
monotonic counter of some kind, and use that counter as the final
arbiter of ordering in the comparison function.
Another way is to set up an array of pointers into the array of
elements, first pointer to first element, second pointer to second
element and so so, and sort the pointer array rather than the element
array. Final arbiter in the comparison function then is the pointer
difference. This works well with, for example, the symbol pointers
returned by _bfd_elf_canonicalize_symtab which point into a symbol
array.
This patch fixes a few places where sorting by symbol pointers is
appropriate, and adds comments where qsort stability is a non-issue.
* elf-strtab.c (strrevcmp): Comment.
* merge.c (strrevcmp): Likewise.
* elf64-ppc.c (compare_symbols): Correct final pointer comparison.
Comment on why comparing pointers ensures a stable sort.
* elflink.c (struct elf_symbol): Add void* to union.
(elf_sort_elf_symbol): Ensure a stable sort with pointer comparison.
(elf_sym_name_compare): Likewise.
(bfd_elf_match_symbols_in_sections): Style fix.
(elf_link_sort_cmp1): Comment.
This patch is a result of noticing messages like the following:
tmpdir/tls32.o: in function `_start':
(.text+0x1c): unresolvable R_PPC_REL24 relocation against symbol `__tls_get_addr_opt'
./ld-new: final link failed: symbol needs debug section which does not exist
The "needs debug section" comes from attempting to use debug info to
find source line information to print the first error message. That
error isn't of interest to the user, and any previous bfd_error value
which might be of interest is overwritten. So save and restore
bfd_error around the fancy error reporting code.
That still doesn't leave us with a clean bfd_error. Now we get
./ld-new: final link failed: nonrepresentable section on output
An unresolvable relocation surely doesn't mean there is some bfd
section that ld doesn't know how to output! Digging into that showed
a _bfd_elf_section_from_bfd_section failure attempting to find an elf
section correcsponding to ".interp". So don't go looking for elf
sections on linker created bfd sections.
And then fix the linker testsuite which expected the bogus message..
bfd/
* elflink.c (elf_fixup_link_order): Don't attempt to find
an elf_section for linker created bfd sections.
ld/
* ldmisc.c (vfinfo): Save and restore bfd_error around bfd
function calls that might set it.
* testsuite/ld-elf/indirect.exp: Don't expect "nonrepresentable
section" message.
This is quite complicated because the CTF section's contents depend on
the final contents of the symtab and strtab, because it has two sections
whose contents are shuffled to be in 1:1 correspondence with the symtab,
and an internal strtab that gets deduplicated against the ELF strtab
(with offsets adjusted to point into the ELF strtab instead). It is
also compressed if large enough, so its size depends on its contents!
So we cannot construct it as early as most sections: we cannot even
*begin* construction until after the symtab and strtab are finalized.
Thankfully there is already one section treated similarly: compressed
debugging sections: the only differences are that compressed debugging
sections have extra handling to deal with their changing name if
compressed (CTF sections are always called ".ctf" for now, though we
have reserved ".ctf.*" against future use), and that compressed
debugging sections have previously-uncompressed content which has to be
stashed away for later compression, while CTF sections have no content
at all until we generate it (very late).
BFD also cannot do the link itself: libctf knows how to do it, and BFD
cannot call libctf directly because libctf already depends on bfd for
file I/O. So we have to use a pair of callbacks, one, examine_strtab,
which allows a caller to examine the symtab and strtab after
finalization (called from elf_link_swap_symbols_out(), right before the
symtabs are written, and after the strtab has been finalized), and one
which actually does the emission (called emit_ctf simply because it is
grouped with a bunch of section-specific late-emission function calls at
the bottom of bfd_elf_final_link, and a section-specific name seems best
for that). emit_ctf is actually called *twice*: once from lang_process
if the emulation suggests that this bfd target does not examine the
symtab or strtab, and once via a bfd callback if it does. (This means
that non-ELF targets still get CTF emitted, even though the late CTF
emission stage is never called for them).
v2: merged with non-ELF support patch: slight commit message
adjustments.
v3: do not spend time merging CTF, or crash, if the CTF section is
explicitly discarded. Do not try to merge or compress CTF unless
linking.
v4: add CTF_COMPRESSION_THRESHOLD. Annul the freed input ctf_file_t's
after writeout: set SEC_IN_MEMORY on the output contents so a future
bfd enhancement knows it could free it. Add SEC_LINKER_CREATED |
SEC_KEEP to avoid having to add .ctf to the linker script. Drop
now-unnecessary ldlang.h-level elf-bfd.h include and hackery around
it. Adapt to elf32.em->elf.em and elf-generic.em->ldelf*.c
changes.
v5: fix tabdamage. Drop #inclusions in .h files: include in .c files,
.em files, and use struct forwards instead. Use bfd_section_is_ctf
inline function rather than SECTION_IS_CTF macro. Move a few
comments.
* Makefile.def (dependencies): all-ld depends on all-libctf.
* Makefile.in: Regenerated.
include/
* bfdlink.h (elf_strtab_hash): New forward.
(elf_sym_strtab): Likewise.
(struct bfd_link_callbacks <examine_strtab>): New.
(struct bfd_link_callbacks <emit_ctf>): Likewise.
bfd/
* elf-bfd.h (bfd_section_is_ctf): New inline function.
* elf.c (special_sections_c): Add ".ctf".
(assign_file_positions_for_non_load_sections): Note that
compressed debugging sections etc are not assigned here. Treat
CTF sections like SEC_ELF_COMPRESS sections when is_linker_output:
sh_offset -1.
(assign_file_positions_except_relocs): Likewise.
(find_section_in_list): Note that debugging and CTF sections, as
well as reloc sections, are assigned later.
(_bfd_elf_assign_file_positions_for_non_load): CTF sections get
their size and contents updated.
(_bfd_elf_set_section_contents): Skip CTF sections: unlike
compressed sections, they have no uncompressed content to copy at
this stage.
* elflink.c (elf_link_swap_symbols_out): Call the examine_strtab
callback right before the strtab is written out.
(bfd_elf_final_link): Don't cache the section contents of CTF
sections: they are not populated yet. Call the emit_ctf callback
right at the end, after all the symbols and strings are flushed
out.
ld/
* ldlang.h: (struct lang_input_statement_struct): Add the_ctf.
(struct elf_sym_strtab): Add forward.
(struct elf_strtab_hash): Likewise.
(ldlang_ctf_apply_strsym): Declare.
(ldlang_write_ctf_late): Likewise.
* ldemul.h (ldemul_emit_ctf_early): New.
(ldemul_examine_strtab_for_ctf): Likewise.
(ld_emulation_xfer_type) <emit_ctf_early>: Likewise.
(ld_emulation_xfer_type) <examine_strtab_for_ctf>: Likewise.
* ldemul.c (ldemul_emit_ctf_early): New.
(ldemul_examine_strtab_for_ctf): Likewise.
* ldlang.c: Include ctf-api.h.
(CTF_COMPRESSION_THRESHOLD): New.
(ctf_output): New. Initialized in...
(ldlang_open_ctf): ... this new function. Open all the CTF
sections in the input files: mark them non-loaded and empty
so as not to copy their contents to the output, but linker-created
so the section gets created in the target.
(ldlang_merge_ctf): New, merge types via ctf_link_add_ctf and
ctf_link.
(ldlang_ctf_apply_strsym): New, an examine_strtab callback: wrap
ldemul_examine_strtab_for_ctf.
(lang_write_ctf): New, write out the CTF section.
(ldlang_write_ctf_late): New, late call via bfd's emit_ctf hook.
(lang_process): Call ldlang_open_ctf, ldlang_merge_ctf, and
lang_write_ctf.
* ldmain.c (link_callbacks): Add ldlang_ctf_apply_strsym,
ldlang_write_ctf_late.
* emultempl/aix.em: Add ctf-api.h.
* emultempl/armcoff.em: Likewise.
* emultempl/beos.em: Likewise.
* emultempl/elf.em: Likewise.
* emultempl/generic.em: Likewise.
* emultempl/linux.em: Likewise.
* emultempl/msp430.em: Likewise.
* emultempl/pe.em: Likewise.
* emultempl/pep.em: Likewise.
* emultempl/ticoff.em: Likewise.
* emultempl/vanilla.em: Likewise.
* ldcref.c: Likewise.
* ldctor.c: Likewise.
* ldelf.c: Likewise.
* ldelfgen.c: Likewise.
* ldemul.c: Likewise.
* ldexp.c: Likewise.
* ldfile.c: Likewise.
* ldgram.c: Likewise.
* ldlex.l: Likewise.
* ldmain.c: Likewise.
* ldmisc.c: Likewise.
* ldver.c: Likewise.
* ldwrite.c: Likewise.
* lexsup.c: Likewise.
* mri.c: Likewise.
* pe-dll.c: Likewise.
* plugin.c: Likewise.
* ldelfgen.c (ldelf_emit_ctf_early): New.
(ldelf_examine_strtab_for_ctf): tell libctf about the symtab and
strtab.
(struct ctf_strsym_iter_cb_arg): New, state to do so.
(ldelf_ctf_strtab_iter_cb): New: tell libctf about
each string in the strtab in turn.
(ldelf_ctf_symbols_iter_cb): New, tell libctf
about each symbol in the symtab in turn.
* ldelfgen.h (struct elf_sym_strtab): Add forward.
(struct elf_strtab_hash): Likewise.
(struct ctf_file): Likewise.
(ldelf_emit_ctf_early): Declare.
(ldelf_examine_strtab_for_ctf): Likewise.
* emultempl/elf-generic.em (LDEMUL_EMIT_CTF_EARLY): Set it.
(LDEMUL_EXAMINE_STRTAB_FOR_CTF): Likewise.
* emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Add
emit_ctf_early and examine_strtab_for_ctf, NULL by default.
* emultempl/armcoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/beos.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/generic.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/linux.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/msp430.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/pe.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/pep.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/ticoff.em (ld_${EMULATION_NAME}_emulation): Likewise.
* emultempl/vanilla.em (ld_vanilla_emulation): Likewise.
* Makefile.am: Pull in libctf (and zlib, a transitive requirement
for compressed CTF section emission). Pass it on to DejaGNU.
* configure.ac: Add AM_ZLIB.
* aclocal.m4: Added zlib.m4.
* Makefile.in: Regenerated.
* testsuite/ld-bootstrap/bootstrap.exp: Use it when relinking ld.
2019-08-16 Martin Liska <mliska@suse.cz>
PR ld/24912
* elflink.c: Report error only for not relocatable.
* linker.c (_bfd_generic_link_add_one_symbol): Do not handle
here lto_slim_object as it's handled in caller.
2019-08-16 Martin Liska <mliska@suse.cz>
PR ld/24912
* object.cc (big_endian>::do_layout): Do not report error,
but only set a flag.
(big_endian>::do_add_symbols): Report error only for when
relocatable.
This patch is a reimplementation of [1] which was submitted in 2015 by
Neil Schellenberger. Copyright issue was sorted out [2] last year.
It proposed a new section (.gnu.xhash) and related dynamic tag
(DT_GNU_XHASH). The new section would be virtually identical to the
existing .gnu.hash except for the translation table (xlat) which would
contain correct MIPS .dynsym indexes corresponding to the hashvals in
chains. This is because MIPS ABI imposes a different ordering on the
dynsyms than the one expected by the .gnu.hash section. Another addition
would be a leading word (ngnusyms) which would contain the number of
entries in the translation table.
In this patch, the new section name and dynamic tag are changed to
reflect the fact that the section should be treated as MIPS-specific
(.MIPS.xhash and DT_MIPS_XHASH).
This patch addresses the alignment issue as reported in [3], which is
caused by the leading word added to the .MIPS.xhash section. Leading word
is removed in this patch, and the number of entries in the translation
table is now calculated using DT_MIPS_SYMTABNO dynamic tag (this is
addressed by the corresponding glibc patch).
Suggestions on coding style in [4] were taken into account. Existing
GNU hash testcase was covered, and another one was added in the MIPS
part of the testsuite.
The other major change is reserving MIPS ABI version 5 for .MIPS.xhash,
marking the need of support for .MIPS.xhash in the dynamic linker (again,
addressed in the corresponding glibc patch). This is something which I
am not sure of, especially after reading [5]. I am confused on whether
this ABI version is reserved for IFUNC, or it can be used for this
purpose.
Already mentioned glibc patch is submitted at:
https://sourceware.org/ml/libc-alpha/2019-06/msg00456.html
[1] https://sourceware.org/ml/binutils/2015-10/msg00057.html
[2] https://sourceware.org/ml/binutils/2018-03/msg00025.html
[3] https://sourceware.org/ml/binutils/2016-01/msg00006.html
[4] https://sourceware.org/ml/binutils/2016-02/msg00097.html
[5] https://sourceware.org/ml/libc-alpha/2016-12/msg00853.html
ld * emulparams/elf32bmip.sh: Add .MIPS.xhash section.
* emulparams/elf32bmipn32-defs.sh: Add .MIPS.xhash section.
* emulparams/elf64bmip-defs.sh: Add .MIPS.xhash section.
* emultempl/mipself.em: Remove mips_after_parse function.
* testsuite/ld-elf/hash.d: Update comment.
* testsuite/ld-mips-elf/hash1.d: New test.
* testsuite/ld-mips-elf/hash1.s: Ditto.
* testsuite/ld-mips-elf/hash1a.d: Remove.
* testsuite/ld-mips-elf/hash1b.d: Ditto.
* testsuite/ld-mips-elf/hash1c.d: Ditto
* testsuite/ld-mips-elf/hash2.d: New test.
* testsuite/ld-mips-elf/mips-elf.exp: New tests.
* testsuite/ld-mips-elf/start.s: New test.
bfd * elf-bfd.h (struct elf_backend_data): New members.
* elflink.c (_bfd_elf_link_create_dynamic_sections): Create
.gnu.hash section if necessary.
(struct collect_gnu_hash_codes): New member.
(elf_gnu_hash_process_symidx): New function name.
(elf_renumber_gnu_hash_syms): Ignore local and undefined
symbols. Record xlat location for every symbol which should have
a .MIPS.xhash entry.
(bfd_elf_size_dynamic_sections): Add DT_GNU_HASH dynamic tag to
dynamic section if necessary.
(GNU_HASH_SECTION_NAME): New define.
(bfd_elf_size_dynsym_hash_dynstr): Get .MIPS.xhash section.
Update the section size info.
* elfxx-mips.c (struct mips_elf_hash_sort_data): New members.
(struct mips_elf_link_hash_entry): New member.
(mips_elf_link_hash_newfunc): Initialize .MIPS.xhash translation
table location.
(mips_elf_sort_hash_table): Initialize the pointer to the
.MIPS.xhash section.
(mips_elf_sort_hash_table_f): Populate the .MIPS.xhash
translation table entry with the symbol dynindx.
(_bfd_mips_elf_section_from_shdr): Add SHT_MIPS_XHASH.
(_bfd_mips_elf_fake_sections): Initialize .MIPS.xhash section
info.
(_bfd_mips_elf_create_dynamic_sections): Create .MIPS.xhash
section.
(_bfd_mips_elf_size_dynamic_sections): Add DT_MIPS_XHASH tag to
dynamic section.
(_bfd_mips_elf_finish_synamic_sections): Add DT_MIPS_XHASH.
(_bfd_mips_elf_final_write_processing): Set .MIPS.xhash section
sh_link info.
(_bfd_mips_elf_get_target_dtag): Get DT_MIPS_XHASH tag.
(MIPS_LIBC_ABI_XHASH): New ABI version enum value.
(_bfd_mips_post_process_headers): Mark the ABI version as
MIPS_LIBC_ABI_XHASH if there exists a .MIPS.xhash section,
but not a .hash section.
(_bfd_mips_elf_record_xhash_symbol): New function. Record a
position in the translation table, associated with the hash
entry.
* elfxx-mips.h (literal_reloc_p): Define
elf_backend_record_xhash_symbol backend hook.
* elfxx-target.h: Initialize elf_backend_record_xhash_symbol
backend hook.
include * elf/mips.h (SHT_GNU_XHASH): New define.
(DT_GNU_XHASH): New define.
binutils * readelf.c (get_mips_dynamic_type): Return MIPS_XHASH dynamic type.
(get_mips_section_type_name): Return MI{S_XHASH name string.
(dynamic_section_mips_val): Initialize the .MIPS.xhash dynamic
info.
(process_symbol_table): Initialize the .MIPS.xhash section
pointer. Adjust the readelf output to support the new section.
(process_object): Set the .MIPS.xhash dynamic info to zero.
This fixes two cases where elf_link_add_object_symbols returns an
error, setting the catch-all bfd_error_bad_value without explaining
the error. The second one is an internal error that can only be
caused by a target elf_add_symbol_hook, so make that one abort. The
first one is my PR24339 fix. PR24339 is another of those fuzzing bugs
and the fix I made catches the problem when loading symbols, rather
than when symbols are used in relocs. While ld is correct to reject
the object file as not complying with the ELF standard, let's be a
little more forgiving for dynamic objects.
PR 24857
PR 24339
* elflink.c (elf_link_add_object_symbols): Report an informative
error on finding local symbols with index equal or greater than
symbol table sh_info. Correct comment. Allow such symbols in
dynamic objects. Abort on NULL section for symbol.
This field effectively became usused a long time ago, perhaps as early
as 1994.
* elf-bfd.h (struct output_elf_obj_tdata): Delete "linker" field.
(elf_linker): Don't define.
* elflink.c (bfd_elf_final_link): Don't set elf_linker.
> Building LLVM 6.0 on FreeBSD/powerpc (devel/llvm60 port) the assertion
> in the subject trips (displays twice) when linking libLTO.so.1. The
> issue has been filed in FreeBSD's bugzilla, at
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=237068 . It appears
> the 'llvm::hashing::detail::get_execution_seed()::seed@@JL_LLVM_6.0'
> symbol is being weakly aliased to an indirect symbol
> __bss_start@@JL_LLVM_6.0. Since __bss_start@@JL_LLVM_6.0 is an
> indirect symbol, it fails the assertion.
I haven't looked under a debugger at your testcase but I think I know
what is going on here. You have a shared library with a weakly
defined llvm::hashing::detail::get_execution_seed()::seed which
happens to be at the same location as __bss_start in that library. At
the time the linker loads symbols for that library, it sees they are
both versioned and thus introduces non-versioned indirect symbols for
them. The linker considers the symbols as possibly being aliases,
setting up h->u.alias and h->is_weakalias such that
__bss_start@@JL_LLVM_6.0 is the definition. No real problem so far,
the definition is bfd_link_hash_defined, except that the zero size, no
type __bss_start symbol possibly should not be considered an alias in
the first place.
Later, __bss_start as defined by the linker script is entered into the
linker symbol table. This is similar to __bss_start being defined by
a regular object file in that ELF symbol resolution rules say that the
value of __bss_start in the library is overridden by __bss_start in
the executable/library being produced. So to accomplish the override,
ld flips __bss_start from being an indirect symbol pointing at
__bss_start@@JL_LLVM_6.0 to __bss_start@@JL_LLVM_6.0 being an indirect
symbol pointing at __bss_start. That's how we get an unexpected
indirect symbol and hit the assert.
What should happen I think, is for the def->def_regular code above the
assert to run in this case. The symbols are no longer aliases.
* elflink.c (_bfd_elf_fix_symbol_flags): If the def for an
alias is no longer bfd_link_hash_defined, clear the alias.
It is possible to create shared libraries on PowerPC using
-ftls-model=inital-exec or -ftls-model=local-exec. The first is half
reasonable, getting you a shared library that can't be dlopen'd but
otherwise is reasonable. The second is quite bad. Not only do you
lose being able to dlopen, the library also has dynamic text
relocations. Worse, the TPREL16_LO, TPREL16_HA and other TPREL16
dynamic relocs emitted were wrong, resulting in wrong values being
applied by ld.so.
Using the first TLS section symbol in dynamic relocations for local
TLS symbols doesn't work. It's wrong because TLS symbols used by TLS
relocs have values relative to the TLS segment, whereas the TLS
section symbols are addresses. This patch instead uses a symbol index
of zero which is used elsewhere by PowerPC on dynamic TLS relocs.
It's not strictly ABI compliant to use a non-TLS symbol with TLS
relocs but symbol index zero can be interpreted as "no symbol". Not
using the first TLS section symbol means it doesn't need to be dynamic.
The patch also fixes a further problem with PowerPC32 dynamic TPREL16*
relocs, which shouldn't have the symbol value in the addend as we do
for non-TLS symbols.
bfd/
* elflink.c (_bfd_elf_omit_section_dynsym_default): Don't keep
tls_sec.
(_bfd_elf_init_1_index_section): Prefer not using TLS sections.
(_bfd_elf_init_2_index_sections): Likewise.
* elf64-ppc.c (ppc64_elf_relocate_section): When emitting dynamic
relocations for local TLS symbols, use STN_UNDEF as the relocation
symbol.
* elf32-ppc.c (ppc_elf_relocate_section): Likewise, and don't
leave TLS symbol value in the addend.
ld/
* testsuite/ld-powerpc/tlsso.r: Update.
* testsuite/ld-powerpc/tlsso32.g: Update.
* testsuite/ld-powerpc/tlsso32.r: Update.
* testsuite/ld-powerpc/tlstocso.r: Update.
* testsuite/ld-cris/tls-dso-dtpoffd2.d: Update.
* testsuite/ld-cris/tls-dso-dtpoffd4.d: Update.
* testsuite/ld-cris/tls-dso-tpoffgotcomm1.d: Update.
* testsuite/ld-cris/tls-gd-1.d: Update.
* testsuite/ld-cris/tls-gd-1h.d: Update.
* testsuite/ld-cris/tls-gd-2.d: Update.
* testsuite/ld-cris/tls-gd-2h.d: Update.
* testsuite/ld-cris/tls-ie-10.d: Update.
* testsuite/ld-cris/tls-ie-11.d: Update.
* testsuite/ld-cris/tls-ie-8.d: Update.
* testsuite/ld-cris/tls-ie-9.d: Update.
* testsuite/ld-cris/tls-js1.d: Update.
* testsuite/ld-cris/tls-ld-4.d: Update.
* testsuite/ld-cris/tls-ld-5.d: Update.
* testsuite/ld-cris/tls-ld-6.d: Update.
* testsuite/ld-cris/tls-ld-7.d: Update.
* testsuite/ld-cris/tls-ldgd-14.d: Update.
* testsuite/ld-cris/tls-ldgd-15.d: Update.
* testsuite/ld-cris/tls-ldgdx-14.d: Update.
* testsuite/ld-cris/tls-ldgdx-15.d: Update.
* testsuite/ld-cris/tls-local-54.d: Update.
* testsuite/ld-cris/tls-local-60.d: Update.
* testsuite/ld-cris/tls-local-61.d: Update.
* testsuite/ld-cris/tls-local-63.d: Update.
* testsuite/ld-cris/tls-local-64.d: Update.
* testsuite/ld-cris/tls-ok-30.d: Update.
* testsuite/ld-cris/tls-ok-32.d: Update.
* testsuite/ld-cris/tls-ok-34.d: Update.
* testsuite/ld-mips-elf/tls-multi-got-1.got: Update.
* testsuite/ld-mips-elf/tls-multi-got-1.r: Update.
* testsuite/ld-mips-elf/tlsdyn-pie-o32.d: Update.
* testsuite/ld-mips-elf/tlsdyn-pie-o32.got: Update.
* testsuite/ld-mips-elf/tlslib-o32-hidden.got: Update.
* testsuite/ld-mips-elf/tlslib-o32-ver.got: Update.
* testsuite/ld-mips-elf/tlslib-o32.got: Update.
* testsuite/ld-s390/tlspic.rd: Update.
* testsuite/ld-s390/tlspic_64.rd: Update.
* testsuite/ld-sparc/tlssunnopic32.rd: Update.
* testsuite/ld-sparc/tlssunnopic64.rd: Update.
* testsuite/ld-sparc/tlssunpic32.rd: Update.
* testsuite/ld-sparc/tlssunpic64.rd: Update.
When undefined non-weak references in IR objects are optimized out
by LTO, we can have weak dynamic referencs to symbols marked with
bfd_link_hash_undefined. We shouldn't complain such undefined weak
dynamic references.
bfd/
PR ld/24486
* elflink.c (elf_link_output_extsym): Don't complain undefined
weak dynamic reference.
ld/
PR ld/24486
* testsuite/ld-plugin/lto.exp: Run PR ld/24486 tests.
* testsuite/ld-plugin/pr24486a.c: New file.
* testsuite/ld-plugin/pr24486b.c: Likewise.
* testsuite/ld-plugin/pr24486c.c: Likewise.
Reverts commit 1ff31e135f, fixing the problem more generally. There
are likely other place that will segfault on a NULL section.
PR 24337
* elf.c (_bfd_elf_rela_local_sym): Revert last change.
(_bfd_elf_rel_local_sym): Likewise.
* elflink.c (elf_link_input_bfd): Use bfd_und_section for
section of symbols with unrecognized shndx.
PR 24332
* elflink.c (elf_link_add_object_symbols): Add new local variable
extversym_end. Initialise it to point to the end of the version
symbol table, if present. Check it when initialising and updating
the ever pointer.
Mark the previous definition from IR object as undefined so that the
generic linker will override it.
bfd/
PR ld/23958
* elflink.c (_bfd_elf_add_default_symbol): Override the previous
definition from IR object.
ld/
PR ld/23958
* testsuite/ld-plugin/lto.exp: Run PR ld/23958 test.
* testsuite/ld-plugin/pr23958.c: New file.
* testsuite/ld-plugin/pr23958.t: Likewise.
When assigning symbol version, we should hide debug symbols defined in
discarded sections from IR objects so that they can be removed later.
bfd/
PR ld/23818
* elflink.c (_bfd_elf_link_assign_sym_version): Hide symbols
defined in discarded input sections.
ld/
PR ld/23818
* testsuite/ld-plugin/lto.exp: Run PR ld/23818 test.
* testsuite/ld-plugin/pr23818.d: New file.
* testsuite/ld-plugin/pr23818.t: Likewise.
* testsuite/ld-plugin/pr23818a.c: Likewise.
* testsuite/ld-plugin/pr23818b.c: Likewise.
PR 23805
* elflink.c (elf_link_input_bfd): Don't segfault on finding
STT_TLS symbols without any TLS sections. Instead, change the
symbol type to STT_NOTYPE.
This patch improves dynobj selection. This allows the testcase in the
PR to proceed further before segfaulting due to other bugs in the
sparc backend.
../ld/ld-new --eh-frame-hdr -m elf_x86_64 -shared -o bug.so.5 bug.o ./libc.so.6 ./crtendS.o
../ld/ld-new: sparc architecture of input file `bug.o' is incompatible with i386:x86-64 output
../ld/ld-new: bug.o: in function `a':
bug.c:(.text+0x4): undefined reference to `_GLOBAL_OFFSET_TABLE_'
../ld/ld-new: bug.c:(.text+0x8): undefined reference to `_GLOBAL_OFFSET_TABLE_'
Segmentation fault
PR 23653
* elflink.c (_bfd_elf_link_create_dynstrtab): Match elf_object_id
too when choosing dynobj.
Prevents getting an error about dynamic symbols in sections indexed
64K+ when .dynsym is discarded.
* elflink.c (elf_link_output_extsym): Do not place symbols into a
discarded .dynsym.
When linker defines a symbol to override a dynamic definition, it should
always clear h->verinfo.verdef so that the symbol won't be associated
with the version information from the dynamic object. This happened to
the symbol "_edata" when creating an unversioned dynamic object linking
against:
1. libKF5ConfigCore.so.5.49.0
2. libKF5CoreAddons.so.5.49.0
3. libKF5I18n.so.5.49.0
4. libKF5DBusAddons.so.5.49.0
5. libQt5Xml.so.5.11.1
6. libQt5DBus.so.5.11.1
7. libQt5Core.so.5.11.1
Among them
libQt5Xml.so.5.11.1
299: 000000000003e000 0 NOTYPE GLOBAL DEFAULT 18 _edata@@Qt_5
libQt5DBus.so.5.11.1
597: 0000000000092018 0 NOTYPE GLOBAL DEFAULT 18 _edata@@Qt_5
libQt5Core.so.5.11.1
2292: 00000000004df640 0 NOTYPE GLOBAL DEFAULT 21 _edata@Qt_5
2293: 00000000004df640 0 NOTYPE GLOBAL DEFAULT 21 _edata@Qt_5
The problem is triggered by 2 duplicated entries of _edata@Qt_5 in
libQt5Core.so.5.11.1 which was created by gold. Before this commit,
ld created the dynamic object with "_edata" in its dynamic symbol table
which was linker defined and associated with the version information
from libQt5Core.so.5.11.1. The code in question was there when the
binutils source was imported to sourceware.org. When such a dynamic
object was used later, we got:
/usr/bin/ld: bin/libKF5Service.so.5.49.0: _edata: invalid version 21 (max 0)
/usr/bin/ld: bin/libKF5Service.so.5.49.0: error adding symbols: bad value
Tested with many ELF targets.
PR ld/23499
* elflink.c (bfd_elf_record_link_assignment): Always clear
h->verinfo.verdef when overriding a dynamic definition.
Remove `-Wshadow' compilation errors:
cc1: warnings being treated as errors
.../bfd/elflink.c: In function 'bfd_elf_final_link':
.../bfd/elflink.c:11722: error: declaration of 'remove' shadows a global declaration
/usr/include/stdio.h:154: error: shadowed declaration is here
which for versions of GCC before 4.8 prevent support for ELF targets
from being built. See also GCC PR c/53066.
bfd/
* elflink.c (bfd_elf_final_link): Rename `remove' local variable
to `remove_section'.
Setting SEC_EXCLUDE for empty .gnu.attributes is too late in the link
process for the linker to remove the section. That must be done in
bfd_elf_final_link, as we do for removed group sections.
* elflink.c (bfd_elf_final_link): Remove zero size .gnu.attributes
sections.
This is a followup to git commit 97196564c7 "Strip global symbol
defined in discarded section". If a symbol defined in a discarded
section was dynamic, that patch left .dynsym with holes (ie. all zero
entries). For example, the following from libstdc++.so:
Symbol table '.dynsym' contains 6090 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 00000000000a74e0 0 SECTION LOCAL DEFAULT 10
2: 0000000000264180 0 SECTION LOCAL DEFAULT 17
3: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_addUserCommitAction
4: 0000000000000000 0 NOTYPE WEAK DEFAULT UND _ITM_memcpyRtWn
5: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
readelf: Warning: local symbol 5 found at index >= .dynsym's sh_info value of 3
6: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
readelf: Warning: local symbol 6 found at index >= .dynsym's sh_info value of 3
[snip]
This patch removes the symbols from .dynsym too.
PR 17550
* elflink.c (_bfd_elf_fix_symbol_flags): Hide dynamic symbols
in discarded sections.
Many ELF targets arrange to emit a number of section symbols in
.dynsym for use by dynamic relocations. This happens before the
dynamic relocations are output, and the need for those symbols
determined. In most cases they are not needed. A proper analysis of
the need for dynamic section symbols is target specific and tedious,
so this patch just excludes them in the obvious case when no
dynamic relocations are present.
The patch also runs the new pr23161 and pr23162 tests on more targets.
bfd/
* elf-bfd.h (struct elf_link_hash_table): Add "dynamic_relocs".
* elflink.c (_bfd_elf_init_2_index_sections): Comment fix.
(_bfd_elf_add_dynamic_entry): Set "dynamic_relocs".
(_bfd_elf_link_renumber_dynsyms): Exclude all section symbols when
"dynamic_relocs" is not set.
* elfxx-mips.c (count_section_dynsyms): Likewise.
ld/
* testsuite/ld-elf/readelf.exp: Delete DUMP and selection of
variant ver_def.vd.
* testsuite/ld-elf/ver_def-tic6x.vd: Delete.
* testsuite/ld-elf/shared.exp: Run most pr23161 and pr23162 tests for
linux, nacl and gnu targets.
* testsuite/ld-mips-elf/mips-elf.exp: Set base_syms to 1.
* testsuite/ld-elf/pr23161a.rd: Don't check reloc type. Allow any
order of __bss_start, _edata and _end.
* testsuite/ld-elf/pr23161b.rd: Don't check plt and dyn relocs.
Allow and order of __bss_start, _edata and _end.
* testsuite/ld-elf/pr23162.rd: Fail if __bss_start, _edata or _end
relocs are present rather than testing for no relocations.
* testsuite/ld-aarch64/gc-plt-relocs.d,
* testsuite/ld-aarch64/ifunc-1-local.d,
* testsuite/ld-aarch64/ifunc-1.d,
* testsuite/ld-aarch64/ifunc-2-local.d,
* testsuite/ld-aarch64/ifunc-2.d,
* testsuite/ld-aarch64/ifunc-21.d,
* testsuite/ld-aarch64/ifunc-3a.d,
* testsuite/ld-arm/farcall-mixed-lib-v4t.d,
* testsuite/ld-arm/farcall-mixed-lib.d,
* testsuite/ld-arm/gc-hidden-1.d,
* testsuite/ld-arm/tls-gdesc-got.d,
* testsuite/ld-arm/tls-lib-loc.d,
* testsuite/ld-arm/tls-longplt-lib.d,
* testsuite/ld-arm/tls-thumb1.d,
* testsuite/ld-cris/libdso-10.d,
* testsuite/ld-cris/libdso-11.d,
* testsuite/ld-cris/libdso-13b.d,
* testsuite/ld-cris/libdso-14.d,
* testsuite/ld-cris/libdso-15.d,
* testsuite/ld-cris/pic-gc-72.d,
* testsuite/ld-cris/pic-gc-73.d,
* testsuite/ld-cris/tls-gc-71.d,
* testsuite/ld-mips-elf/mips16-pic-4a.nd,
* testsuite/ld-mips-elf/pic-and-nonpic-3a.dd,
* testsuite/ld-mips-elf/pie-n32.d,
* testsuite/ld-mips-elf/pie-n64.d,
* testsuite/ld-mips-elf/pie-o32.d: Update for removed dynamic
section symbols.
bfd_hide_sym_by_version can't be used to check if a versioned symbol is
hidden. This patch adds _bfd_elf_link_hide_sym_by_version to support
both versioned and unversioned symbols by extracting versioned symbol
check from _bfd_elf_link_assign_sym_version.
bfd/
PR ld/23194
* elf-bfd.h (_bfd_elf_link_hide_sym_by_version): New.
* elflink.c (_bfd_elf_link_hide_versioned_symbol): New function.
Extracted from _bfd_elf_link_assign_sym_version.
(_bfd_elf_link_hide_sym_by_version): New function.
(_bfd_elf_link_assign_sym_version): Use
_bfd_elf_link_hide_versioned_symbol.
* elfxx-x86.c (_bfd_x86_elf_link_symbol_references_local): Call
_bfd_elf_link_hide_sym_by_version instead of
bfd_hide_sym_by_version. Don't check unversioned symbol.
ld/
PR ld/23194
* testsuite/ld-i386/pr23194.d: Expect only R_386_GLOB_DAT
against foobar.
* testsuite/ld-i386/pr23194.map: Add foobar.
* testsuite/ld-x86-64/pr23194.map: Likewise.
* testsuite/ld-i386/pr23194.s: Add a common foobar symbol.
* testsuite/ld-x86-64/pr23194.s: Likewise.
* testsuite/ld-x86-64/pr23194.d: Expect only R_X86_64_GLOB_DAT
against foobar.
If a symbol is made dynamic by --dynamic-list, it has non-IR reference.
bfd/
PR ld/22983
* elflink.c (bfd_elf_link_mark_dynamic_symbol): Set
non_ir_ref_dynamic if a symbol is made dynamic by --dynamic-list.
ld/
PR ld/22983
* testsuite/ld-plugin/lto.exp: Run PR ld/22983 test.
* testsuite/ld-plugin/pr22983.d: New file.
* testsuite/ld-plugin/pr22983.t: Likewise.
* testsuite/ld-plugin/pr22983a.c: Likewise.
* testsuite/ld-plugin/pr22983b.c: Likewise.
Extend
commit b7c871edcd
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Wed May 17 07:57:15 2017 -0700
Mark debug sections referenced by kept debug sections
to handle the local debug definition section.
bfd/
PR ld/20882
* elflink.c (elf_gc_mark_debug_section): Also check the local
debug definition section.
ld/
PR ld/20882
* testsuite/ld-gc/pr20882.d: Also dump and check .debug_abbrev
section.
* testsuite/ld-gc/pr20882b.s: Add .debug_abbrev section.
Alan Modra
Christian Eggers
Nick Alcock
Martin Liska
Mihailo Stojanovic
H.J. Lu
Nick Clifton
Egeyar Bagcioglu
Maciej W. Rozycki