place_orphan handled ELF SHT_REL/SHT_RELA specially, output_rel_find
didn't. This mismatch was a bug and also meant it was possible to
craft an object where ld accessed section->name out of bounds.
PR 24042
* emultempl/elf32.em (output_rel_find): Drop "sec" param. Add
"rela".
(gld${EMULATION_NAME}_place_orphan): Use sh_type to calculate
"rela" param of output_rel_find when ELF. Tidy uses of elfinput.
We have not only removed all unsupported and obsolete code, but also supported lost of new features,
including better link-time relaxations and TLS implementations. Besides, the files generated by the
newly assembler and linker usually get higher performance and more optimized code size.
ld * emultempl/nds32elf.em (hyper_relax): New variable.
(nds32_elf_create_output_section_statements):
the parameters of bfd_elf32_nds32_set_target_option
(PARSE_AND_LIST_PROLOGUE, PARSE_AND_LIST_OPTIONS,
PARSE_AND_LIST_ARGS_CASES): Add new option --mhyper-relax.
* emultempl/nds32elf.em (nds32_elf_after_open): Updated.
* emultempl/nds32elf.em (tls_desc_trampoline): New variable.
* (nds32_elf_create_output_section_statements): Updated.
* (nds32_elf_after_parse): Disable relaxations when PIC is enable.
* (PARSE_AND_LIST_PROLOGUE, PARSE_AND_LIST_OPTIONS,
PARSE_AND_LIST_ARGS_CASES): Add new option --m[no-]tlsdesc-trampoline.
include * elf/nds32.h: Remove the unused target features.
* dis-asm.h (disassemble_init_nds32): Declared.
* elf/nds32.h (E_NDS32_NULL): Removed.
(E_NDS32_HAS_DSP_INST, E_NDS32_HAS_ZOL): New.
* opcode/nds32.h: Ident.
(N32_SUB6, INSN_LW): New macros.
(enum n32_opcodes): Updated.
* elf/nds32.h: Doc fixes.
* elf/nds32.h: Add R_NDS32_LSI.
* elf/nds32.h: Add new relocations for TLS.
gas * config/tc-nds32.c: Remove the unused target features.
(nds32_relax_relocs, md_pseudo_table, nds32_elf_record_fixup_exp,
nds32_set_elf_flags_by_insn, nds32_insert_relax_entry,
nds32_apply_fix): Likewise.
(nds32_no_ex9_begin): Removed.
* config/tc-nds32.c (add_mapping_symbol_for_align,
make_mapping_symbol, add_mapping_symbol): New functions.
* config/tc-nds32.h (enum mstate): New.
(nds32_segment_info_type): Likewise.
* configure.ac (--enable-dsp-ext, --enable-zol-ext): New options.
* config.in: Regenerated.
* configure: Regenerated.
* config/tc-nds32.c (nds32_dx_regs):
Set the value according to the configuration.
(nds32_perf_ext, nds32_perf_ext2, nds32_string_ext, nds32_audio_ext):
Likewise.
(nds32_dsp_ext): New variable. Set the value according to the
configuration.
(nds32_zol_ext): Likewise.
(asm_desc, nds32_pseudo_opcode_table): Make them static.
(nds32_set_elf_flags_by_insn): Updated.
(nds32_check_insn_available): Updated.
(nds32_str_tolower): New function.
* config/tc-nds32.c (relax_table): Updated.
(md_begin): Updated.
(md_assemble): Use XNEW macro to allocate space for `insn.info',
and then remember to free it.
(md_section_align): Cast (-1) to ValueT.
(nds32_get_align): Cast (~0U) to addressT.
(nds32_relax_branch_instructions): Updated.
(md_convert_frag): Add new local variable `final_r_type'.
(invalid_prev_frag): Add new bfd_boolean parameter `relax'.
All callers changed.
* config/tc-nds32.c (struct nds32_relocs_pattern): Add `insn' field.
(struct nds32_hint_map): Add `option_list' field.
(struct suffix_name, suffix_table): Remove the unused `pic' field.
(do_pseudo_b, do_pseudo_bal): Remove the suffix checking.
(do_pseudo_la_internal, do_pseudo_pushpopm): Indent.
(relax_hint_bias, relax_hint_id_current): New static variables.
(reset_bias, relax_hint_begin): New variables.
(nds_itoa): New function.
(CLEAN_REG, GET_OPCODE): New macros.
(struct relax_hint_id): New.
(nds32_relax_hint): For .relax_hint directive, we can use `begin'
and `end' to mark the relax pattern without giving exactly id number.
(nds32_elf_append_relax_relocs): Handle the case that the .relax_hint
directives are attached to pseudo instruction.
(nds32_elf_save_pseudo_pattern): Change the second parameter from
instruction's opcode to byte code.
(nds32_elf_build_relax_relation): Add new bfd_boolean parameter
`pseudo_hint'.
(nds32_lookup_pseudo_opcode): Fix the overflow issue.
(enum nds32_insn_type): Add N32_RELAX_ALU1 and N32_RELAX_16BIT.
(nds32_elf_record_fixup_exp, relax_ls_table, hint_map,
nds32_find_reloc_table, nds32_match_hint_insn, nds32_parse_name):
Updated.
* config/tc-nds32.h (MAX_RELAX_NUM): Extend it to 6.
(enum nds32_relax_hint_type): Merge NDS32_RELAX_HINT_LA and
NDS32_RELAX_HINT_LS into NDS32_RELAX_HINT_LALS. Add
NDS32_RELAX_HINT_LA_PLT, NDS32_RELAX_HINT_LA_GOT and
NDS32_RELAX_HINT_LA_GOTOFF.
* config/tc-nds32.h (relax_ls_table): Add floating load/store
to gp relax pattern.
(hint_map, nds32_find_reloc_table): Likewise.
* configure.ac: Define NDS32_LINUX_TOOLCHAIN.
* configure: Regenerated.
* config.in: Regenerated.
* config/tc-nds32.h (enum nds32_ramp): Updated.
(enum nds32_relax_hint_type): Likewise.
* config/tc-nds32.c: Include "errno.h" and "limits.h".
(relax_ls_table): Add TLS relax patterns.
(nds32_elf_append_relax_relocs): Attach BFD_RELOC_NDS32_GROUP on
each instructions of TLS patterns.
(nds32_elf_record_fixup_exp): Updated.
(nds32_apply_fix): Likewise.
(suffix_table): Add TLSDESC suffix.
binutils* testsuite/binutils-all/objcopy.exp: Set the unsupported reloc number
from 215 to 255 for NDS32.
bfd * elf32-nds32.c (nds32_elf_relax_loadstore):
Remove the unused target features.
(bfd_elf32_nds32_set_target_option): Remove the unused parameters.
(nds32_elf_relax_piclo12, nds32_elf_relax_letlslo12,
nds32_elf_relax_letlsadd, nds32_elf_relax_letlsls,
nds32_elf_relax_pltgot_suff, nds32_elf_relax_got_suff
nds32_elf_relax_gotoff_suff, calculate_plt_memory_address,
calculate_plt_offset, calculate_got_memory_address,
nds32_elf_check_dup_relocs): Removed.
All callers changed.
* elf32-nds32.h: Remove the unused macros and defines.
(elf_nds32_link_hash_table): Remove the unused variable.
(bfd_elf32_nds32_set_target_option): Update prototype.
(nds32_elf_ex9_init): Removed.
* elf32-nds32.c (nds32_convert_32_to_16): Updated.
* elf32-nds32.c (HOWTO2, HOWTO3): Define new HOWTO macros
to initialize array nds32_elf_howto_table in any order
without lots of EMPTY_HOWTO.
(nds32_reloc_map): Updated.
* reloc.c: Add BFD_RELOC_NDS32_LSI.
* bfd-in2.h: Regenerated.
* bfd/libbfd.h: Regenerated.
* elf32-nds32.c (nds32_elf_relax_howto_table): Add R_NDS32_LSI.
(nds32_reloc_map): Likewise.
(nds32_elf_relax_flsi): New function.
(nds32_elf_relax_section): Support floating load/store relaxation.
* elf32-nds32.c (NDS32_GUARD_SEC_P, elf32_nds32_local_gp_offset):
New macro.
(struct elf_nds32_link_hash_entry): New `offset_to_gp' field.
(struct elf_nds32_obj_tdata): New `offset_to_gp' and `hdr_size' fields.
(elf32_nds32_allocate_local_sym_info, nds32_elf_relax_guard,
nds32_elf_is_target_special_symbol, nds32_elf_maybe_function_sym):
New functions.
(nds32_info_to_howto_rel): Add BFD_ASSERT.
(bfd_elf32_bfd_reloc_type_table_lookup, nds32_elf_link_hash_newfunc,
nds32_elf_link_hash_table_create, nds32_elf_relocate_section,
nds32_elf_relax_loadstore, nds32_elf_relax_lo12, nds32_relax_adjust_label,
bfd_elf32_nds32_set_target_option, nds32_fag_mark_relax): Updated.
(nds32_elf_final_sda_base): Improve it to find the better gp value.
(insert_nds32_elf_blank): Must consider `len' when inserting blanks.
* elf32-nds32.h (bfd_elf32_nds32_set_target_option): Update prototype.
(struct elf_nds32_link_hash_table): Add new variable `hyper_relax'.
* elf32-nds32.c (elf32_nds32_allocate_dynrelocs): New function.
(create_got_section): Likewise.
(allocate_dynrelocs, nds32_elf_size_dynamic_sections,
nds32_elf_relocate_section, nds32_elf_finish_dynamic_symbol): Updated.
(nds32_elf_check_relocs): Fix the issue that the shared library may
has TEXTREL entry in the dynamic section.
(nds32_elf_create_dynamic_sections): Enable to call readonly_dynrelocs
since the TEXTREL issue is fixed in the nds32_elf_check_relocs.
(nds32_elf_finish_dynamic_sections): Update and add DT_RELASZ
dynamic entry.
(calculate_offset): Remove the unused parameter `pic_ext_target' and
related codes.
All callers changed.
(elf_backend_dtrel_excludes_plt): Disable it temporarily since it
will cause some errors for our test cases.
* elf32-nds32.c (nds32_elf_merge_private_bfd_data): Allow to link the
generic object.
* reloc.c: Add TLS relocations.
* libbfd.h: Regenerated.
* bfd-in2.h: Regenerated.
* elf32-nds32.h (struct section_id_list_t): New.
(elf32_nds32_lookup_section_id, elf32_nds32_check_relax_group,
elf32_nds32_unify_relax_group, nds32_elf_unify_tls_model):
New prototypes.
(elf32_nds32_compute_jump_table_size, elf32_nds32_local_tlsdesc_gotent):
New macro.
(nds32_insertion_sort, bfd_elf32_nds32_set_target_option,
elf_nds32_link_hash_table): Updated.
* elf32-nds32.c (enum elf_nds32_tls_type): New.
(struct elf32_nds32_relax_group_t, struct relax_group_list_t): New.
(elf32_nds32_add_dynreloc, patch_tls_desc_to_ie, get_tls_type,
fls, ones32, list_insert, list_insert_sibling, dump_chain,
elf32_nds32_check_relax_group, elf32_nds32_lookup_section_id,
elf32_nds32_unify_relax_group, nds32_elf_unify_tls_model): New functions.
(elf_nds32_obj_tdata): Add new fields.
(elf32_nds32_relax_group_ptr, nds32_elf_local_tlsdesc_gotent): New macros.
(nds32_elf_howto_table): Add TLS relocations.
(nds32_reloc_map): Likewise.
(nds32_elf_copy_indirect_symbol, nds32_elf_size_dynamic_sections,
nds32_elf_finish_dynamic_symbol, elf32_nds32_allocate_local_sym_info,
nds32_elf_relocate_section, bfd_elf32_nds32_set_target_option,
nds32_elf_check_relocs, allocate_dynrelocs): Updated.
(nds32_elf_relax_section): Call nds32_elf_unify_tls_model.
(dtpoff_base): Rename it to `gottpof' and then update it.
opcodes * nds32-asm.c (operand_fields): Remove the unused fields.
(nds32_opcodes): Remove the unused instructions.
* nds32-dis.c (nds32_ex9_info): Removed.
(nds32_parse_opcode): Updated.
(print_insn_nds32): Likewise.
* nds32-asm.c (config.h, stdlib.h, string.h): New includes.
(LEX_SET_FIELD, LEX_GET_FIELD): Update defines.
(nds32_asm_init, build_operand_hash_table, build_keyword_hash_table,
build_opcode_hash_table): New functions.
(nds32_keyword_table, nds32_keyword_count_table, nds32_field_table,
nds32_opcode_table): New.
(hw_ktabs): Declare it to a pointer rather than an array.
(build_hash_table): Removed.
* nds32-asm.h (enum): Add SYN_INPUT, SYN_OUTPUT, SYN_LOPT,
SYN_ROPT and upadte HW_GPR and HW_INT.
* nds32-dis.c (keywords): Remove const.
(match_field): New function.
(nds32_parse_opcode): Updated.
* disassemble.c (disassemble_init_for_target):
Add disassemble_init_nds32.
* nds32-dis.c (eum map_type): New.
(nds32_private_data): Likewise.
(get_mapping_symbol_type, is_mapping_symbol, nds32_symbol_is_valid,
nds32_add_opcode_hash_table, disassemble_init_nds32): New functions.
(print_insn_nds32): Updated.
* nds32-asm.c (parse_aext_reg): Add new parameter.
(parse_re, parse_re2, parse_aext_reg): Only reduced registers
are allowed to use.
All callers changed.
* nds32-asm.c (keyword_usr, keyword_sr): Updated.
(operand_fields): Add new fields.
(nds32_opcodes): Add new instructions.
(keyword_aridxi_mx): New keyword.
* nds32-asm.h (enum): Add NASM_ATTR_DSP_ISAEXT, HW_AEXT_ARIDXI_MX
and NASM_ATTR_ZOL.
(ALU2_1, ALU2_2, ALU2_3): New macros.
* nds32-dis.c (nds32_filter_unknown_insn): Updated.
We have an issue in the MIPS backend, with the handling of undefined
hidden and internal weak symbols. References to such symbols are
supposed to resolve to 0 according to the ELF gABI[1]:
"Unresolved weak symbols have a zero value."
and the 64-bit MIPS psABI[2]:
"If a symbol with one of these [hidden or internal] attributes has no
definition within the executable/DSO being linked, then it must be
resolved to allocated space if common, resolved to zero if weak, or an
error reported otherwise."
however if a GOT relocation is used, then a local GOT entry is created
and used to satisfy the reference. Such an entry is then (in DSO and
PIE binaries) subject to the usual load-time relocation, which means a
non-zero value will be returned if the base address is non-zero. This
will defeat the usual run-time sequence like:
void a (void) __attribute__ ((visibility ("hidden"), weak));
void
x (void)
{
if (a)
a ();
}
This can be reproduced with this simple code:
$ cat libtest.c
extern int a __attribute__ ((visibility ("hidden"), weak));
int *
x (void)
{
return &a;
}
$ cat test.c
int *x (void);
int
main (void)
{
printf ("a: %p\n", x ());
return 0;
}
$ gcc -shared -fPIC -o libtest.so libtest.c
$ gcc -o test test.c -Wl,-rpath,$(pwd) libtest.so
$ ./test
a: 0x77184000
$
The usual approach targets take is making all the steps required to
assign a GOT entry for the symbol referred, and then leave its contents
at zero with no dynamic relocation attached, therefore ensuring that the
value does not change at load time. However this is not going to work
with the implicitly relocated GOT the MIPS psABI specifies[3]:
"The dynamic linker relocates the global offset table by first adding
the difference between the base where the shared object is loaded and
the value of the dynamic tag DT_MIPS_BASE_ADDRESS to all local global
offset table entries."
and we cannot therefore use the local GOT part.
And we cannot offhand use the global part either, as the symbol would
then have to be exported and possibly wrongly preempt symbols in other
modules involved in the dynamic load, because as per the ELF gABI[1] we
are not allowed to enter a hidden or internal symbol into the dynamic
symbol table (and then use its associated GOT entry):
"A hidden symbol contained in a relocatable object must be either
removed or converted to STB_LOCAL binding by the link-editor when the
relocatable object is included in an executable file or shared object."
and:
"An internal symbol contained in a relocatable object must be either
removed or converted to STB_LOCAL binding by the link-editor when the
relocatable object is included in an executable file or shared object."
So we have to choose something else.
Our choice is further limited by the need for the reference associated
with the GOT relocation to stay within the signed 16-bit limit from the
GOT pointer base register, while being compliant with the ELF gABI and
the MIPS psABI. However as Alan Modra has observed[4] one possibility
is to edit (relax) the code such that the GOT reference is removed
altogether.
Based on these observations then modify MIPS BFD linker backend code to:
1. Interpret code associated with GOT relocations and relax the usual LW
or LD instructions into a corresponding immediate load operation that
places the value of 0 in the intended register, while leaving the GOT
entry allocated and initialized as usually.
2. Leave any other instructions associated with GOT relocations in place
and instead redirect the reference to a global GOT entry associated
with a special `__gnu_absolute_zero' symbol created for this purpose,
whose value is 0, SHN_ABS section marks it absolute, binding is
global and export class protected, ensuring that the locally provided
value is always used at load time, and that the value is not
relocated by the dynamic loader.
3. Adjust any high-part GOT relocation used, typically associated with
a LUI instruction, accordingly, so that run-time consistency is
maintained, either by resolving to the original entry if the
instruction associated with the corresponding low-part GOT relocation
has been relaxed to an immediate load (in which case the value loaded
with LUI will be overwritten), or by also redirecting the reference
to `__gnu_absolute_zero' to complete the GOT access sequence if that
symbol has been used.
4. Add a target `elf_backend_hide_symbol' hook, for the three MIPS ABIs,
which prevents the `__gnu_absolute_zero' symbol from being forced
local, to ensure that the redirection works and the symbol remains
global/protected with existing linker scripts unchanged.
5. Observing the issue with handling SHN_ABS symbols in the GNU dynamic
loader, covered by glibc PR 19818, set the EI_ABIVERSION field in the
ELF file header produced to 4 (ABI_ABSOLUTE) if `__gnu_absolute_zero'
symbol has been produced and the target configured indicates the GNU
operating system, so that broken versions of the GNU dynamic loader
gracefully reject the file in loading rather than going astray. Keep
EI_ABIVERSION at the original value for other operating systems or if
no `__gnu_absolute_zero' symbol has been made.
The name of the special `__gnu_absolute_zero' has no meaning other than
how a human reader can interpret it, as it is ignored in dynamic loading
in the handling of the scenarios concerned. This is because the symbol
resolves locally, and it's only the symbol's attributes that matter so
that the associated GOT entry remains unchanged at load time.
Therefore the name is somewhat arbitrary, observing however the need to
use the name space reserved for the system so that it does not conflict
with a possible user symbol, and hence the leading underscore, and also
the `gnu' infix to denote a GNU feature. Other implementations wishing
to address the problem in a similar way may choose a different name and
have the solution still work, possibly with a mixture of modules used in
a dynamic having symbols of different names provided, which will however
not interact with each other due to the protected export class.
The symbol can be referred explicitly, however the name is an internal
implementation detail rather than a part of the ABI, and therefore no
specific semantics is guaranteed.
One limitation of this change is that if `__gnu_absolute_zero' has been
already defined, then we do not wipe the old definition and all kinds of
odd behavior can result. This is however like with other symbols we
internally define, such as `_GLOBAL_OFFSET_TABLE_' or `__rld_map', and
therefore left as a possible future enhancement.
As an optimization the relaxation of LW and LD instructions to a load of
immediate zero is always made, even SVR4 PIC code for code that will end
up in a regular (non-PIE) executable, because there is a cache advantage
with the avoidance of a load from the GOT, even if it is otherwise
guaranteed to remain zero. It does not reliably happen though, due to a
symbol exportation issue affecting executables, covered by PR ld/21805.
One existing test case needs to be updated, as it triggers relaxation
introduced with this change and consequently linker output does not
match expectations anymore. As we want to keep the original issue
covered with the test case modify it then to use the LWL instruction in
place of LW, and adjust the output expected accordingly.
References:
[1] "System V Application Binary Interface - DRAFT - 19 October 2010",
The SCO Group, Section "Symbol Table",
<http://www.sco.com/developers/gabi/2012-12-31/ch4.symtab.html>
[2] "64-bit ELF Object File Specification, Draft Version 2.5", MIPS
Technologies / Silicon Graphics Computer Systems, Order Number
007-4658-001, Section 2.5 "Symbol Table", p. 22,
<http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf>
[3] "SYSTEM V APPLICATION BINARY INTERFACE, MIPS RISC Processor
Supplement, 3rd Edition", Section "Global Offset Table", p. 5-10,
<http://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf>
[4] "Undo dynamic symbol state after regular object sym type mismatch",
<https://sourceware.org/ml/binutils/2017-07/msg00265.html>
bfd/
PR ld/21375
* elfxx-mips.h (_bfd_mips_elf_hide_symbol): New prototype.
(_bfd_mips_elf_linker_flags): Update prototype.
* elf32-mips.c (elf_backend_hide_symbol): New macro.
* elf64-mips.c (elf_backend_hide_symbol): Likewise.
* elfn32-mips.c (elf_backend_hide_symbol): Likewise.
* elfxx-mips.c (mips_elf_link_hash_table): Add
`use_absolute_zero' and `gnu_target' members.
(mips_elf_record_global_got_symbol): Call
`_bfd_mips_elf_hide_symbol' rather than
`_bfd_elf_link_hash_hide_symbol'.
(mips_use_local_got_p): Return FALSE if the symbol is absolute.
(mips_elf_obtain_contents): Reorder function.
(mips_elf_nullify_got_load): New function.
(mips_elf_calculate_relocation): Add `contents' parameter.
Nullify GOT loads or if it is not possible, then redirect GOT
relocations to the `__gnu_absolute_zero' symbol, for references
that are supposed to resolve to zero.
(mips_elf_define_absolute_zero): New function.
(_bfd_mips_elf_check_relocs): Prepare for arrangements made in
`mips_elf_calculate_relocation' for references made via the GOT
that are supposed to resolve to zero.
(_bfd_mips_elf_hide_symbol): New function.
(_bfd_mips_elf_linker_flags): Add the `gnu_target' parameter,
set the `gnu_target' member of the MIPS hash table.
(MIPS_LIBC_ABI_ABSOLUTE): New enumeration constant.
(_bfd_mips_post_process_headers): Use it.
ld/
PR ld/21375
* emultempl/mipself.em: Set `gnu_target' according to ${target}.
(mips_create_output_section_statements): Update call to
`_bfd_mips_elf_linker_flags'.
* testsuite/ld-mips-elf/pr21334.s: Use LWL rather than LW.
* testsuite/ld-mips-elf/pr21334.dd: Update accordingly.
git commit 702d16713 broke expressions using CONSTANT(COMMONPAGESIZE)
in ALIGN or SUBALIGN of output section statements, because these
optional fields were evaluated at script parse time and the patch in
question delayed setting of config.commonpagesize. The right thing to
do is keep the tree representation of those fields for later
evaluation.
PR 23571
* ldlang.h (section_alignment): Make it an expression tree.
(subsection_alignment): Likewise.
* ldlang.c (topower): Delete.
(output_section_statement_newfunc): Adjust initialization.
(init_os): Evaluate section_alignment.
(lang_size_sections_1): Likewise.
(size_input_section): Evaluate subsection_alignment.
(lang_enter_output_section_statement): Don't evaluate here.
(lang_new_phdr): Use exp_get_vma rather than exp_get_value_int.
* ldexp.h (exp_get_value_int): Delete.
(exp_get_power): Declare.
* ldexp.c (exp_get_value_int): Delete.
(exp_get_power): New function.
* emultempl/pe.em (place_orphan): Build expression for section
alignment.
* emultempl/pep.em (place_orphan): Likewise.
* testsuite/ld-scripts/pr23571.d,
* testsuite/ld-scripts/pr23571.t: New test.
* testsuite/ld-scripts/align.exp: Run it.
We force __ehdr_start to defined in before_allocation, then restore
the type and a union after dynamic symbols have been allocated.
The union contains a number of structs, all starting with a "next"
pointer, and various fields depending on the symbol type. The old
code restored the entire union, but it isn't necessary to restore the
"next" pointer, and in fact it could be wrong if __ehdr_start happened
to be last on the list and some symbols were added before restoring.
* emultempl/elf32.em (before_allocation): Don't restore
__ehdr_start u.*.next pointer.
This patch series is a new binutils port for C-SKY processors, including support for both the V1 and V2 processor variants. V1 is derived from the MCore architecture while V2 is substantially different, with mixed 16- and 32-bit instructions, a larger register set, a different (but overlapping) ABI, etc. There is support for bare-metal ELF targets and Linux with both glibc and uClibc.
This code is being contributed jointly by C-SKY Microsystems and Mentor Graphics. C-SKY is responsible for the technical content and has proposed Lifang Xia and Yunhai Shang as port maintainers. (Note that C-SKY does have a corporate copyright assignment on file with the FSF.) Mentor Graphics' role has been cleaning up the code, adding documentation and additional test cases, etc, to address issues we anticipated reviewers would complain about.
bfd * Makefile.am (ALL_MACHINES, ALL_MACHINES_CFILES): Add C-SKY.
(BFD32_BACKENDS, BFD_BACKENDS_CFILES): Likewise.
* Makefile.in: Regenerated.
* archures.c (enum bfd_architecture): Add bfd_arch_csky and
related bfd_mach defines.
(bfd_csky_arch): Declare.
(bfd_archures_list): Add C-SKY.
* bfd-in.h (elf32_csky_build_stubs): Declare.
(elf32_csky_size_stubs): Declare.
(elf32_csky_next_input_section: Declare.
(elf32_csky_setup_section_lists): Declare.
* bfd-in2.h: Regenerated.
* config.bfd: Add C-SKY.
* configure.ac: Likewise.
* configure: Regenerated.
* cpu-csky.c: New file.
* elf-bfd.h (enum elf_target_id): Add C-SKY.
* elf32-csky.c: New file.
* libbfd.h: Regenerated.
* reloc.c: Add C-SKY relocations.
* targets.c (csky_elf32_be_vec, csky_elf32_le_vec): Declare.
(_bfd_target_vector): Add C-SKY target vector entries.
binutils* readelf.c: Include elf/csky.h.
(guess_is_rela): Handle EM_CSKY.
(dump_relocations): Likewise.
(get_machine_name): Likewise.
(is_32bit_abs_reloc): Likewise.
include * dis-asm.h (csky_symbol_is_valid): Declare.
* opcode/csky.h: New file.
opcodes * Makefile.am (TARGET_LIBOPCODES_CFILES): Add csky-dis.c.
* Makefile.in: Regenerated.
* configure.ac: Add C-SKY.
* configure: Regenerated.
* csky-dis.c: New file.
* csky-opc.h: New file.
* disassemble.c (ARCH_csky): Define.
(disassembler, disassemble_init_for_target): Add case for ARCH_csky.
* disassemble.h (print_insn_csky, csky_get_disassembler): Declare.
gas * Makefile.am (TARGET_CPU_CFILES): Add entry for C-SKY.
(TARGET_CPU_HFILES, TARGET_ENV_HFILES): Likewise.
* Makefile.in: Regenerated.
* config/tc-csky.c: New file.
* config/tc-csky.h: New file.
* config/te-csky_abiv1.h: New file.
* config/te-csky_abiv1_linux.h: New file.
* config/te-csky_abiv2.h: New file.
* config/te-csky_abiv2_linux.h: New file.
* configure.tgt: Add C-SKY.
* doc/Makefile.am (CPU_DOCS): Add entry for C-SKY.
* doc/Makefile.in: Regenerated.
* doc/all.texi: Set CSKY feature.
* doc/as.texi (Overview): Add C-SKY options.
(Machine Dependencies): Likewise.
* doc/c-csky.texi: New file.
* testsuite/gas/csky/*: New test cases.
ld * Makefile.am (ALL_EMULATION_SOURCES): Add C-SKY emulations.
(ecskyelf.c, ecskyelf_linux.c): New rules.
* Makefile.in: Regenerated.
* configure.tgt: Add C-SKY.
* emulparams/cskyelf.sh: New file.
* emulparams/cskyelf_linux.sh: New file.
* emultempl/cskyelf.em: New file.
* gen-doc.texi: Add C-SKY.
* ld.texi: Likewise.
(Options specific to C-SKY targets): New section.
* testsuite/ld-csky/*: New tests.
With this patch dedicated linker scripts can be generated for partial
relro triggered by defining GENERATE_RELRO_SCRIPT in the target
specific scripts.
This is necessary for e.g. S/390 where usually the .got.plt comes
first and prevents the relro segment from being extended across the
non-plt GOT entries.
The patch started with the work from Marcin taken from the mwk user
branches. However, the patch needed substantial changes due to the
'separate code' feature which got committed in the meantime.
ld/ChangeLog:
2018-07-18 Andreas Krebbel <krebbel@linux.ibm.com>
Marcin Kościelnicki <koriakin@0x04.net>
* emultempl/elf32.em: Add code to pick dedicated linker scripts
for partial relro.
* genscripts.sh: Generate dedicated linker scripts for partial relro.
In case params.thumb_entry_symbol has its default NULL value, using it
to print a warning in gld${EMULATION_NAME}_finish results in a crash.
Use h->root.string instead which either points to
params.thumb_entry_symbol name or to entry_symbol name.
2018-07-09 Christophe Lyon <christophe.lyon@linaro.org>
* emultempl/armelf.em (gld${EMULATION_NAME}_finish): Use the right
symbol name in case of warning.
Change-Id: Iec61a833c0ad538b1440bf326ba67834c314dd63
This patch adds the analysis part of PLT call optimization, enabling
the code added with the previous patch that actually performs the
optimization.
Gold support is not available yet.
bfd/
* elf64-ppc.c (struct _ppc64_elf_section_data): Add has_pltcall field.
(struct ppc_link_hash_table): Add can_convert_all_inline_plt.
(ppc64_elf_check_relocs): Set has_pltcall.
(ppc64_elf_adjust_dynamic_symbol): Discard some PLT entries.
(ppc64_elf_inline_plt): New function.
(ppc64_elf_size_dynamic_sections): Discard some PLT entries for locals.
* elf64-ppc.h (ppc64_elf_inline_plt): Declare.
* elf32-ppc.c (has_pltcall): Define.
(struct ppc_elf_link_hash_table): Add can_convert_all_inline_plt.
(ppc_elf_check_relocs): Set has_pltcall.
(ppc_elf_inline_plt): New function.
(ppc_elf_adjust_dynamic_symbol): Discard some PLT entries.
(ppc_elf_size_dynamic_sections): Likewise.
* elf32-ppc.h (ppc_elf_inline_plt): Declare.
ld/
* emultempl/ppc64elf.em (no_inline_plt): New var.
(ppc_before_allocation): Call ppc64_elf_inline_plt.
(enum ppc64_opt): Add OPTION_NO_INLINE_OPT.
(PARSE_AND_LIST_LONGOPTS, PARSE_AND_LIST_OPTIONS,
PARSE_AND_LIST_ARGS_CASES): Handle --no-inline-optimize.
* emultemps/ppc32elf.em (no_inline_opt): New var.
(prelim_size_sections): New function, extracted from..
(ppc_before_allocation): ..here. Call ppc_elf_inline_plt.
(enum ppc32_opt): Add OPTION_NO_INLINE_OPT.
(PARSE_AND_LIST_LONGOPTS, PARSE_AND_LIST_OPTIONS,
PARSE_AND_LIST_ARGS_CASES): Handle --no-inline-optimize.
The current scheme where we output PLT relocs for global symbols in
finish_dynamic_symbol, and PLT relocs for local symbols when
outputting stubs does not work if PLT entries are to be used for
inline PLT sequences against non-dynamic globals or local symbols.
bfd/
* elf64-ppc.c (ppc_build_one_stub): Move output of PLT relocs
for local symbols to..
(write_plt_relocs_for_local_syms): ..here. New function.
(ppc64_elf_finish_dynamic_symbol): Move output of PLT relocs for
global symbols to..
(build_global_entry_stubs_and_plt): ..here. Rename from
build_global_entry_stubs.
(ppc64_elf_build_stubs): Always call build_global_entry_stubs_and_plt.
Call write_plt_relocs_for_local_syms.
* elf32-ppc.c (get_sym_h): New function.
(ppc_elf_relax_section): Use get_sym_h.
(ppc_elf_relocate_section): Move output of PLT relocs and glink
stubs for local symbols to..
(ppc_finish_symbols): ..here. New function.
(ppc_elf_finish_dynamic_symbol): Move output of PLT relocs for
global syms to..
(write_global_sym_plt): ..here. New function.
* elf32-ppc.h (ppc_elf_modify_segment_map): Delete attribute.
(ppc_finish_symbols): Declare.
ld/
* ppc32elf.em (ppc_finish): Call ppc_finish_symbols.
This patch deals with the auto-import feature. There are 2 versions
of this feature: the original one, which was piggybacked on the OS
loader with an optional help from the runtime (--enable-auto-import
--enable-runtime-pseudo-reloc-v1) and is still the one mostly
documented in the sources and manual; the enhanced one by Kai Tietz,
which is entirely piggybacked on the runtime (--enable-auto-import
--enable-runtime-pseudo-reloc-v2) and is the default for Mingw and
Cygwin nowadays.
The implementation is inefficient because of pe[p]_find_data_imports:
for every undefined symbol, the function walks the entire set of
relocations for all the input files and does a direct name comparison
for each of them.
This is easily fixable by using a hash-based map for v1 and a simple
hash table for v2. This patch leaves v1 alone and only changes v2.
It also factors out pe[p]_find_data_imports into a common function,
removes old cruft left and right, and attempts to better separate
the implementations of v1 and v2 in the code.
ld/
* emultempl/pe.em (U_SIZE): Delete.
(pe_data_import_dll): Likewise.
(make_import_fixup): Return void, take 4th parameter and pass it down
in call to pe_create_import_fixup.
(pe_find_data_imports): Move to...
(gld_${EMULATION_NAME}_after_open): Run the stdcall fixup pass after
the auto-import pass and add a guard before running the latter.
* emultempl/pep.em (U_SIZE): Delete.
(pep_data_import_dll): Likewise.
(make_import_fixup): Return void, take 4th parameter and pass it down
in call to pe_create_import_fixup.
(pep_find_data_imports): Move to...
(gld_${EMULATION_NAME}_after_open): Run the stdcall fixup pass after
the auto-import pass and add a guard before running the latter.
* pe-dll.c (runtime_pseudp_reloc_v2_init): Change type to bfd_boolean.
(pe_walk_relocs_of_symbol): Rename into...
(pe_walk_relocs): ...this. Add 2 more parameters,4th parameter to the
callback prototype and pass 4th parameter in calls to the callback.
If the import hash table is present, invoke the callback on the reloc
if the symbol name is in the table.
(pe_find_data_imports): ...here. Take 2 parameters. Build an import
hash table for the pseudo-relocation support version 2. When it is
built, walk the relocations only once at the end; when it is not, do
not build a fixup when the symbol isn't part of an import table.
Issue the associated warning only after a first fixup is built.
(tmp_seq2): Delete.
(make_singleton_name_imp): Likewise.
(make_import_fixup_mark): Return const char * and a stable string.
(make_import_fixup_entry): Do not deal with the pseudo-relocation
support version 2.
(make_runtime_pseudo_reloc): Factor out code and fix formatting.
(pe_create_import_fixup): Add 5th parameter. Clearly separate the
pseudo-relocation support version 2 from the rest. Fix formatting.
* pe-dll.h (pe_walk_relocs_of_symbol): Delete.
(pe_find_data_imports): Declare.
(pe_create_import_fixup): Add 5th parameter.
* pep-dll.c (pe_data_import_dll): Delete.
(pe_find_data_imports): Define.
(pe_walk_relocs_of_symbol): Delete.
* pep-dll.h (pep_walk_relocs_of_symbol): Delete.
(pep_find_data_imports): Declare.
(pep_create_import_fixup): Add 5th parameter.
* ld.texinfo (--enable-auto-import): Adjust to new implementation.
This patch adds --enable-separate-code to ld configure to turn on
-z separate-code by default and enables it by default for Linux/x86.
This avoids mixing code pages with data to improve cache performance
as well as security.
To reduce x86-64 executable and shared object sizes, the maximum page
size is reduced from 2MB to 4KB when -z separate-code is turned on by
default. Note: -z max-page-size= can be used to set the maximum page
size.
We compared SPEC CPU 2017 performance before and after this change on
Skylake server. There are no any significant performance changes.
Everything is mostly below +/-1%.
bfd/
* config.in: Regenerated.
* configure: Likewise.
* configure.ac: Add --enable-separate-code.
(DEFAULT_LD_Z_SEPARATE_CODE): New AC_DEFINE_UNQUOTED. Default
to 1 for Linux/x86 targets,
* elf64-x86-64.c (ELF_MAXPAGESIZE): Set to 0x1000 if
DEFAULT_LD_Z_SEPARATE_CODE is 1.
ld/
* NEWS: Mention --enable-separate-code.
* configure.ac: Add --enable-separate-code.
(DEFAULT_LD_Z_SEPARATE_CODE): New AC_DEFINE_UNQUOTED.
* configure.tgt: Default ac_default_ld_z_separate_code to 1 for
Linux/x86 targets.
* config.in: Regenerated.
* configure: Likewise.
* emultempl/elf32.em (gld${EMULATION_NAME}_before_parse): Set
link_info.separate_code DEFAULT_LD_Z_SEPARATE_CODE.
This reverts most of commit 1be5d8d3bb.
Left in place are addition of --no-plt-align to some ppc32 ld tests
and the ld.texinfo --no-plt-thread-safe fix.
Since all ELF linkers call check_relocs after opening all inputs, we
can fold after_allocation into before_allocation so that local dynamic
symbols will be placed before global dynamic symbols in .dynsym section.
This fixed:
FAIL: Common symbol override test (auxiliary shared object build)
FAIL: ld-elf/pr19617a
FAIL: ld-elf/pr19698
for i386-solaris2.12 and x86_64-solaris2.12 targets.
PR ld/22728
* emultempl/solaris2.em (elf_solaris2_after_allocation): Fold
into ...
(elf_solaris2_before_allocation): This.
(LDEMUL_AFTER_ALLOCATION): Removed.
Asking for ppc32 plt call stubs to be aligned at 32 byte boundaries
didn't quite work. For ld.bfd they were spaced 32 bytes apart, but
only started on a 16 byte boundary. ld.gold also didn't get it right.
Finding that bug made me check over the ppc64 plt stub alignment,
where I found that negative values for alignment (meaning align to
minimize boundary crossing) were not accepted. Since no one has
complained about that, I guess I could have removed the feature from
ld.bfd documentation, but I've opted instead to correct the code.
I've also added an optional alignment paramenter for ppc32
--plt-align, for some consistency with gold and ppc64 ld.bfd.
bfd/
* elf32-ppc.c (ppc_elf_create_glink): Correct alignment of .glink.
* elf64-ppc.c (ppc64_elf_size_stubs): Handle negative plt_stub_align.
(ppc64_elf_build_stubs): Likewise.
gold/
* powerpc.cc (param_plt_align): New function supplying default
--plt-align values. Use it..
(Stub_table::plt_call_align): ..here, and..
(Output_data_glink::global_entry_align): ..here.
(Stub_table::stub_align): Correct 32-bit minimum alignment.
ld/
* emultempl/ppc32elf.em: Support optional --plt-align arg.
* emultempl/ppc64elf.em: Support negative --plt-align arg.
This is in preparation for the next patch adding Spectre variant 2
mitigation for PowerPC and PowerPC64. Besides tidying code involved
in stub output (to reduce the number of places where bctr is output),
the patch adds some user visible features:
1) PowerPC64 ELFv2 global entry stubs now are aligned under the
control of --plt-align, with a default alignment of 32 bytes.
2) PowerPC64 __glink_PLTresolve is no longer padded out with nops.
3) PowerPC32 PLT stubs are aligned under the control of --plt-align,
with the default alignment being 16 bytes as before.
4) The PowerPC32 branch/nop table emitted before __glink_PLTresolve
is now smaller in many cases. It was sized incorrectly when the
__tls_get_addr_opt stub was used, and unnecessarily included space
for local ifuncs.
bfd/
* elf32-ppc.c (GLINK_ENTRY_SIZE): Add parameters, handle
__tls_get_addr_opt, and alignment sizing.
(TLS_GET_ADDR_GLINK_SIZE): Delete.
(is_nonpic_glink_stub): Don't use GLINK_ENTRY_SIZE.
(ppc_elf_get_synthetic_symtab): Recognize stubs spaced at 4, 6,
or 8 insns.
(ppc_elf_link_hash_table_create): Init new ppc_elf_params field.
(allocate_dynrelocs): Use new GLINK_ENTRY_SIZE.
(ppc_elf_size_dynamic_sections): Likewise. Size branch table
by PLT reloc count.
(write_glink_stub): Handle __tls_get_addr_opt stub.
Pad out to size given by GLINK_ENTRY_SIZE.
(ppc_elf_relocate_section): Adjust write_glink_stub call.
(ppc_elf_finish_dynamic_symbol): Likewise.
(ppc_elf_finish_dynamic_sections): Write PLTresolve without using
insn array since so many need rewriting.
* elf32-ppc.h (struct ppc_elf_params): Add plt_stub_align.
* elf64-ppc.c (GLINK_PLTRESOLVE_SIZE): Rename from
GLINK_CALL_STUB_SIZE. Add htab param and evaluate to size without
nops. Adjust all uses.
(ppc64_elf_get_synthetic_symtab): Don't use GLINK_CALL_STUB_SIZE
in glink_vma calculation.
(struct ppc_link_hash_table): Add global_entry section pointer.
(create_linkage_sections): Create separate section for global
entry stubs.
(PPC_LO, PPC_HI, PPC_HA): Move earlier.
(size_global_entry_stubs): Handle sizing for aligned stubs.
(ppc64_elf_size_dynamic_sections): Handle global_entry alloc,
and don't stash end of glink branch table in rawsize.
(ppc_build_one_stub): Rewrite stub size calculations.
(build_global_entry_stubs): Use new section.
(ppc64_elf_build_stubs): Don't pad __glink_PLTresolve with nops.
Build lazy link stubs out to end of section. Build global entry
stubs in new section.
gold/
* options.h (plt_align): Support for PowerPC32 too.
* powerpc.cc (Stub_table::stub_align): Heed --plt-align for 32-bit.
(Stub_table::plt_call_size, branch_stub_size): Tidy.
(Stub_table::plt_call_align): Implement using stub_align.
(Output_data_glink::global_entry_align): New function.
(Output_data_glink::global_entry_off): New function.
(Output_data_glink::global_entry_address): Use global_entry_off.
(Output_data_glink::pltresolve_size): New function, replacing
pltresolve_size_ constant. Update all uses.
(Output_data_glink::add_global_entry): Align offset.
(Output_data_glink::set_final_data_size): Use global_entry_align.
(Stub_table::do_write): Don't pad __glink_PLTrelsolve with nops.
Tidy stub output. Use global_entry_off.
ld/
* emultempl/ppc32elf.em (params): Init new field.
(enum ppc32_opt): New enum to define OPTION_* values. Add
OPTION_PLT_ALIGN and OPTION_NO_PLT_ALIGN.
(PARSE_AND_LIST_LONGOPTS): Handle new options.
(PARSE_AND_LIST_ARGS_CASES): Likewise.
(PARSE_AND_LIST_OPTIONS): Likewise. Break up help output.
* emultempl/ppc64elf.em (ppc_add_stub_section): Init alignment
correctly for negative --plt-stub-align.
* testsuite/ld-powerpc/elfv2exe.d,
* testsuite/ld-powerpc/elfv2so.d,
* testsuite/ld-powerpc/relbrlt.d,
* testsuite/ld-powerpc/relbrlt.s,
* testsuite/ld-powerpc/tlsexe.d,
* testsuite/ld-powerpc/tlsexe.r,
* testsuite/ld-powerpc/tlsexe32.d,
* testsuite/ld-powerpc/tlsexe32.g,
* testsuite/ld-powerpc/tlsexe32.r,
* testsuite/ld-powerpc/tlsexetoc.d,
* testsuite/ld-powerpc/tlsexetoc.r,
* testsuite/ld-powerpc/tlsopt5_32.d,
* testsuite/ld-powerpc/tlsso.d,
* testsuite/ld-powerpc/tlstocso.d: Update for changed stub order.
Currently we have no obvious way to revert the action of the "-z defs"
command line option. The "--unresolved-symbols=ignore-in-object-files"
does pretty much what is needed, but it is non-obvious and it also
touches the setting for reporting unresolved symbol references from
shared libraries. So I am proposing adding a "-z undefs" option to be
the inverse of "-z defs". (I thought that "-z nodefs" might be
confusing since it implies banning all definitions, rather than
allowing them).
In addition the description of the "-z defs" option in the linker
documentation is misleading in one place, where it says:
'defs'
Disallows undefined symbols in object files. Undefined
symbols in shared libraries are still allowed.
whereas later on it gets it right:
'-z defs'
Report unresolved symbol references from regular object files.
This is done even if the linker is creating a non-symbolic shared
library. The switch '--[no-]allow-shlib-undefined' controls the
behaviour for reporting unresolved references found in shared
libraries being linked in.
* emultempl/elf32.em (_handle_option): Add support for "-z undefs"
as the opposite of "-z defs".
* ld.texinfo: Document the new option. Update the description of
the -z defs option to make it clear that it does generate an error
if an undefined symbol reference is found in an object file whilst
creating a shared library.
* NEWS: Document this new feature.
The new "-z separate-code" option will generate separate code LOAD
segment which must be in wholly disjoint pages from any other data.
include/
PR ld/22393
* bfdlink.h (bfd_link_info): Add separate_code.
ld/
PR ld/22393
* NEWS: Mention "-z separate-code".
* emultempl/elf32.em (gld${EMULATION_NAME}_get_script): Get
builtin linker scripts and return linker scripts from disk for
"-z separate-code".
(gld${EMULATION_NAME}_handle_option): Handle "-z separate-code"
and "-z noseparate-code".
* genscripts.sh: Generate linker scripts for "-z separate-code".
(LD_FLAG): Set to *textonly for "-z separate-code".
* ld.texinfo: Document "-z separate-code".
* lexsup.c (elf_shlib_list_options): Add linker help messsages
for "-z separate-code" and "-z noseparate-code".
* scripttempl/elf.sc (SEPARATE_TEXT): New
(TEXT_SEGMENT_ALIGN): Likewise.
Use ${TEXT_SEGMENT_ALIGN} to align and pad text segment to
${MAXPAGESIZE}.
PR 22419
* emultempl/v850elf.em (v850_create_output_section_statements):
New function. Generate an error if attempting to convert the
format of the output file.
* testsuite/ld-unique/pr21529.d: Skip for the V850.
* testsuite/ld-elf/pr21884.d: Skip for the V850.
We currently delete bytes by shifting an entire BFD backwards to
overwrite the bytes we no longer need. The result is that relaxing a
BFD is quadratic time.
This patch adds an additional relocation that specifies a byte range
that will be deleted from the final object file, and adds a relaxation
pass (between the existing passes that delete bytes and the alignment
pass) that actually deletes the bytes. Note that deletion is still
quadratic time, and nothing uses R_RISCV_DELETE yet.
I've been meaning to go convert all the other relaxations to use
R_RISCV_DELETE and then make it faster, but this patch has been sitting
around for months so it looks like that won't happen for a bit. The
PCREL->GPREL relaxation that comes next uses this, and since we've been
using these two patches out of tree since I wrote them months ago I
figure it's better to just get them in now. I (or someone else :)) can
convert all the relocations later...
R_RISCV_DELETE will never be emitted into ELF objects, so therefor isn't
exposed to the rest of binutils. As such, we're not considering this as
part of the ABI.
bfd/ChangeLog
2017-10-19 Palmer Dabbelt <palmer@dabbelt.com>
* elfnn-riscv (R_RISCV_DELETE): New define.
(_bfd_riscv_relax_delete): New function.
(perform_relocation): Handle R_RISCV_DELETE.
(_bfd_riscv_relax_section): Likewise.
ld/ChangeLog
2017-10-19 Palmer Dabbelt <palmer@dabbelt.com>
* emultempl/riscvelf.em (riscv_elf_before_allocation): Add a
third relaxation pass.
I believe we should be warning if ld is given both --no-dynamic-linker
and -z dynamic-undefined-weak. The two options are contradictory, the
first says an executable has no dynamic interpreter to resolve dynamic
symbols, while the second is asking for dynamic symbols to be emitted.
(And even if a static PIE's relocation code, which is needed to
process R_*_RELATIVE relocs, could process symbols, there are no
DT_NEEDED dynamic objects to define such symbols.)
I also think that dynamic_undefined_weak is the right flag to control
whether undefined weaks are made dynamic, whether in static PIEs or
anywhere else. So force it to 0 for static PIEs, fixing PR 22269 for
powerpc and any other target where the backend usually defaults to
undefined weaks being made dynamic.
This patch introduces regressions. I'd normally not do that, but
these are all in very recently added test cases, or expose bugs in the
x86 backend. The test cases were added after I'd made it known that
this patch or one like it was imminent.
PR 22269
* emultempl/elf32.em (after_parse): Warn on --no-dynamic-linker
-z dynamic-undefined-weak combination. Set dynamic_undefined_weak
to zero when nointerp.
This function shouldn't be called directly, except from backend code.
bfd/
* elflink.c (_bfd_elf_adjust_dynamic_symbol): Call
elf_backend_hide_symbol, not _bfd_elf_link_hash_hide_symbol.
(bfd_elf_define_start_stop): Likewise.
ld/
* emultempl/elf32.em (before_allocation): Call
elf_backend_hide_symbol, not _bfd_elf_link_hash_hide_symbol.
Formatting.
This changes the PowerPC64 --plt-align option to perform the usual
alignment of code as suggested by its name, as well as the previous
behaviour of padding so as to reduce boundary crossing. The old
behaviour is had by using a negative parameter.
The default is also changed to align plt stub code by default to 32
byte boundaries, the point being to get better bctr branch prediction
on power8 and power9 hardware.
bfd/
* elf64-ppp.c (plt_stub_pad): Handle positive and negative
plt_stub_align.
ld/
* ld.texinfo (--plt-align): Describe new behaviour of option.
* emultempl/ppc64elf.em (params): Default plt_stub_align to 5.
* testsuite/ld-powerpc/powerpc.exp: Pass --no-plt-align for
selected tests.
* testsuite/ld-powerpc/relbrlt.d: Pass --no-plt-align.
* testsuite/ld-powerpc/elfv2so.d: Adjust expected output.
* emultempl/elf32.em (handle_option): Accept the -z globalaudit
command line option.
* lexsup.c (elf_static_list_options): Add -z globalaudit.
* ld.texinfo: Document the support for the new command line
option.
* NEWS: Mention the new feature.
* testsuite/ld-elf/audit.exp: Add a test of the -z globalaudit
command line option.
* testsuite/ld-elf/globalaudit.rd: New file: Expected output from
readelf.
PR ld/21884
* testsuite/ld-elf/pr21884.d: Add AVR, HPPA, IA64, M68HC1x and
SCORE to list of targets not supporting file format changes during
linking.
* testsuite/ld-unique/pr21529.d: Likewise.
* emultempl/avrelf.em (_before_allocation): Skip for non-ELF
output formats.
(avr_elf_create_output_section_statements): Fail if the output
format is not ELF.
(avr_finish): Do not access the ELF header in non-ELF format
output bfds.
* emultempl/m68hc1xelf.em (_before_allocation): Skip for non-ELF
output formats.
(m68hc11elf_create_output_section_statements): Fail if the putput
format is not ELF.
(m68hc11elf_after_allocation): Skip for non-ELF output formats.