mirror/binutils-gdb
2
0
Fork 0
mirror of https://sourceware.org/git/binutils-gdb.git synced 2024-12-09 04:21:49 +08:00
Code Issues Packages Projects Releases Wiki Activity
109,567 Commits 385 Branches 134 Tags 552 MiB
089169c003
Commit Graph

171 Commits

Author SHA1 Message Date
Alan Modra
ff66e8c5be PR28751 mbind2a / mbind2b regressions on powerpc*-linux 
include/
	* bfdlink.h (struct bfd_link_info): Add commonpagesize_is_set.
ld/
	PR 28751
	* emultempl/elf.em (handle_option): Set commonpagesize_is_set.
	* ldelf.c (ldelf_after_parse): Don't error when only one of
	-z max-page-size or -z common-page-size is given, correct the
	other value to make it sane.
	* testsuite/ld-elf/elf.exp (mbind2a, mbind2b): Do not pass
	-z max-page-size.
 2022-01-14 22:02:23 +10:30
H.J. Lu
6a91be8666 ld: Initial DT_RELR support 
Add a -z pack-relative-relocs option to enable DT_RELR and create a
relr.dyn section for DT_RELR.  DT_RELR is implemented with the linker
relaxation infrastructure, but it doesn't require the --relax option
enabled.  -z pack-relative-relocs implies -z combreloc.  -z nocombreloc
implies -z nopack-relative-relocs.

-z pack-relative-relocs is chosen over the similar option in lld,
--pack-dyn-relocs=relr, to implement a glibc binary lockout mechanism
with a special glibc version symbol, to avoid random crashes of DT_RELR
binaries with the existing glibc binaries.

bfd/

	* elf-bfd.h (elf_link_hash_table): Add srelrdyn.
	* elflink.c (_bfd_elf_link_create_dynamic_sections): Create a
	.relr.dyn section for DT_RELR.

include/

	* bfdlink.h (bfd_link_info): Add enable_dt_relr.

ld/

	* News: Mention -z pack-relative-relocs and
	-z nopack-relative-relocs.
	* ld.texi: Document -z pack-relative-relocs and
	-z nopack-relative-relocs.
	* ldelf.c (ldelf_after_parse): Disable DT_RELR if not building
	PIE nor shared library.  Add 3 spare dynamic tags for DT_RELR,
	DT_RELRSZ and DT_RELRENT.
	* ldlang.c (lang_relax_sections): Also enable relaxation if
	DT_RELR is enabled.
	* emulparams/elf32_x86_64.sh: Source dt-relr.sh.
	* emulparams/elf_i386.sh: Likewise.
	* emulparams/elf_x86_64.sh: Likewise.
	* emulparams/dt-relr.sh: New file.
	* scripttempl/elf.sc: Support .relr.dyn.
 2022-01-12 06:04:29 -08:00
H.J. Lu
74e315dbfe elf: Set p_align to the minimum page size if possible 
Currently, on 32-bit and 64-bit ARM, it seems that ld generates p_align
values of 0x10000 even if no section alignment is greater than 0x1000.
The issue is more general and probably affects other targets with multiple
page sizes.

While file layout absolutely must take 64K page size into account, that
does not have to be reflected in the p_align value.  If running on a 64K
kernel, the file will be loaded at a 64K page boundary by necessity. On
a 4K kernel, 64K alignment is not needed.

The glibc loader has been fixed to honor p_align:

https://sourceware.org/bugzilla/show_bug.cgi?id=28676

similar to kernel:

commit ce81bb256a224259ab686742a6284930cbe4f1fa
Author: Chris Kennelly <ckennelly@google.com>
Date:   Thu Oct 15 20:12:32 2020 -0700

    fs/binfmt_elf: use PT_LOAD p_align values for suitable start address

This means that on 4K kernels, we will start to do extra work for 64K
p_align, but this pointless for pretty much all binaries (whose section
alignment rarely exceeds 16).

The minimum page size is used, instead of the maximum section alignment
due to this glibc bug:

https://sourceware.org/bugzilla/show_bug.cgi?id=28688

It has been fixed in glibc 2.35.  But linker output must work on existing
glibc binaries.

1. Set p_align to the minimum page size while laying out segments aligning
to the maximum page size or section alignment.  The run-time loader can
align segments to the minimum page size or above, depending on system page
size.
2. If -z max-page-size=NNN is used, p_align will be set to the maximum
page size or the largest section alignment.
3. If a section requires alignment higher than the minimum page size,
don't set p_align to the minimum page size.
4. If a section requires alignment higher than the maximum page size,
set p_align to the section alignment.
5. For objcopy, when the minimum page size != the maximum page size,
p_align may be set to the minimum page size while segments are aligned
to the maximum page size.  In this case, the input p_align will be
ignored and the maximum page size will be used to align the ouput
segments.
6. Update linker to disallow the common page size > the maximum page size.
7. Update linker to avoid the common page size > the maximum page size.
8. Adjust pru_irq_map-1.d to expect p_align == sh_addralign:

Section Headers:
  [Nr] Name   Type            Addr     Off    Size   ES Flg Lk Inf Al
  [ 0]        NULL            00000000 000000 000000 00      0   0  0
  [ 1] .text  PROGBITS        20000000 00007c 000004 00  AX  0   0  4
...
Program Headers:
  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
  LOAD           0x000074 0x00000000 0x00000000 0x00008 0x00008 RW  0x1
  LOAD           0x00007c 0x20000000 0x20000000 0x00004 0x00004 R E 0x4

vs.

Section Headers:
  [Nr] Name   Type            Addr     Off    Size   ES Flg Lk Inf Al
  [ 0]        NULL            00000000 000000 000000 00      0   0  0
  [ 1] .text  PROGBITS        20000000 00007c 000004 00  AX  0   0  4
...
Program Headers:
  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
  LOAD           0x000074 0x00000000 0x00000000 0x00008 0x00008 RW  0x1
  LOAD           0x00007c 0x20000000 0x20000000 0x00004 0x00004 R E 0x1

To enable this linker optimization, the backend should define ELF_P_ALIGN
to ELF_MINPAGESIZE.

bfd/

	PR ld/28689
	PR ld/28695
	* elf-bfd.h (elf_backend_data): Add p_align.
	* elf.c (assign_file_positions_for_load_sections): Set p_align
	to the default p_align value while laying out segments aligning
	to maximum page size or section alignment.
	(elf_is_p_align_valid): New function.
	(copy_elf_program_header): Call elf_is_p_align_valid to determine
	if p_align is valid.
	* elfxx-target.h (ELF_P_ALIGN): New.  Default to 0.
	(elfNN_bed): Add ELF_P_ALIGN.
	* elfxx-x86.h (ELF_P_ALIGN): New.  Set to ELF_MINPAGESIZE.

include/

	PR ld/28689
	PR ld/28695
	* bfdlink.h (bfd_link_info): Add maxpagesize_is_set.

ld/

	PR ld/28689
	PR ld/28695
	* emultempl/elf.em (gld${EMULATION_NAME}_handle_option): Set
	link_info.maxpagesize_is_set for -z max-page-size=NNN.
	* ldelf.c (ldelf_after_parse): Disallow link_info.commonpagesize
	> link_info.maxpagesize.
	* testsuite/ld-elf/elf.exp: Pass -z max-page-size=0x4000 to
	linker to build mbind2a and mbind2b.
	* testsuite/ld-elf/header.d: Add -z common-page-size=0x100.
	* testsuite/ld-elf/linux-x86.exp: Add PR ld/28689 tests.
	* testsuite/ld-elf/p_align-1.c: New file.
	* testsuite/ld-elf/page-size-1.d: New test.
	* testsuite/ld-elf/pr26936.d: Add -z common-page-size=0x1000.
	* testsuite/ld-elf/seg.d: Likewise.
	* testsuite/ld-scripts/rgn-at5.d: Likewise.
	* testsuite/ld-pru/pru_irq_map-1.d: Append 1 to name.  Adjust
	expected PT_LOAD segment alignment.
	* testsuite/ld-pru/pru_irq_map-2.d: Append 2 to name.
	* testsuite/ld-scripts/pr23571.d: Add -z max-page-size=0x1000.
 2022-01-05 05:06:18 -08:00
Alan Modra
a2c5833233 Update year range in copyright notice of binutils files 
The result of running etc/update-copyright.py --this-year, fixing all
the files whose mode is changed by the script, plus a build with
--enable-maintainer-mode --enable-cgen-maint=yes, then checking
out */po/*.pot which we don't update frequently.

The copy of cgen was with commit d1dd5fcc38ead reverted as that commit
breaks building of bfp opcodes files.
 2022-01-02 12:04:28 +10:30
H.J. Lu
6f365fda85 elf: Add GNU_PROPERTY_1_NEEDED check 
If GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS is set on any input
relocatable files:

1. Don't generate copy relocations.
2. Turn off extern_protected_data since it implies
GNU_PROPERTY_NO_COPY_ON_PROTECTED.
3. Treate reference to protected symbols with indirect external access
as local.
4. Set GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS on output.
5. When generating executable, clear this bit when there are non-GOT or
non-PLT relocations in input relocatable files without the bit set.
6. Add -z [no]indirect-extern-access to control indirect external access.

bfd/

	* elf-bfd (elf_obj_tdata): Add has_indirect_extern_access.
	(elf_has_indirect_extern_access): New.
	* elf-properties.c (_bfd_elf_parse_gnu_properties): Set
	elf_has_indirect_extern_access and elf_has_no_copy_on_protected
	when seeing GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS.
	(elf_write_gnu_propertie): Add an argument to pass link_info.
	Set needed_1_p for GNU_PROPERTY_1_NEEDED in memory.
	(_bfd_elf_link_setup_gnu_properties): Handle
	GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS for
	-z indirect-extern-access.  Set nocopyreloc to true and
	extern_protected_data to false for indirect external access.
	(_bfd_elf_convert_gnu_properties): Updated.
	* elf32-i386.c (elf_i386_check_relocs): Set
	non_got_ref_without_indirect_extern_access on legacy non-GOT or
	non-PLT references.
	* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
	* elflink.c (_bfd_elf_symbol_refs_local_p): Return true for
	STV_PROTECTED symbols with indirect external access.
	* elfxx-x86.c (_bfd_x86_elf_adjust_dynamic_symbol): Clear
	indirect_extern_access for legacy non-GOT/non-PLT references.
	* elfxx-x86.h (elf_x86_link_hash_entry): Add
	non_got_ref_without_indirect_extern_access.

include/

	* bfdlink.h (bfd_link_info): Add indirect_extern_access and
	needed_1_p.  Change nocopyreloc to int.

ld/

	* NEWS: Mention -z [no]indirect-extern-access
	* ld.texi: Document -z [no]indirect-extern-access
	* ldmain.c (main): Initialize link_info.indirect_extern_access
	to -1.
	* emulparams/extern_protected_data.sh: Support
	-z [no]indirect-extern-access.
	* testsuite/ld-elf/indirect-extern-access-1.rd: New file
	* testsuite/ld-elf/indirect-extern-access-1a.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-1b.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2.rd: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2a.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2b.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-3.rd: Likewise.
	* testsuite/ld-elf/indirect-extern-access.S: Likewise.
	* testsuite/ld-elf/property-1_needed-1b.d: Likewise.
	* testsuite/ld-elf/property-1_needed-1c.d: Likewise.
	* testsuite/ld-x86-64/indirect-extern-access.rd: Likewise.
	* testsuite/ld-x86-64/protected-data-1.h: Likewise.
	* testsuite/ld-x86-64/protected-data-1a.c: Likewise.
	* testsuite/ld-x86-64/protected-data-1b.c: Likewise.
	* testsuite/ld-x86-64/protected-data-2a.S: Likewise.
	* testsuite/ld-x86-64/protected-data-2b.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2a.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2b.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2c.c: Likewise.
	* testsuite/ld-elf/linux-x86.exp: Run test with
	GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS.
	* testsuite/ld-x86-64/x86-64.exp: Run tests for protected
	function and data with indirect external access.
 2021-07-08 18:14:31 -07:00
H.J. Lu
a8dde0a211 ld: Limit cache size and add --max-cache-size=SIZE 
When link_info.keep_memory is true, linker caches the relocation
information and symbol tables of input files in memory.  When there
are many input files with many relocations, we may run out of memory.
Add --max-cache-size=SIZE to set the maximum cache size.

bfd/

	PR ld/18028
	* bfd.c (bfd): Add alloc_size.
	* elf-bfd.h (_bfd_elf_link_info_read_relocs): New.
	* elf32-i386.c (elf_i386_check_relocs): Use _bfd_link_keep_memory.
	Update cache_size.
	* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
	* elflink.c (_bfd_elf_link_read_relocs): Renamed to ...
	(_bfd_elf_link_info_read_relocs): This.  Update cache_size.
	(_bfd_elf_link_read_relocs): New.
	(_bfd_elf_link_check_relocs): Call _bfd_elf_link_info_read_relocs
	instead of _bfd_elf_link_read_relocs.
	(elf_link_add_object_symbols): Likewise.
	(elf_link_input_bfd): Likewise.
	(init_reloc_cookie_rels): Likewise.
	(init_reloc_cookie): Update cache_size.  Call
	_bfd_elf_link_info_read_relocs instead of
	_bfd_elf_link_read_relocs.
	(link_info_ok): New.
	(elf_gc_smash_unused_vtentry_relocs): Updated.  Call
	_bfd_elf_link_info_read_relocs instead of
	_bfd_elf_link_read_relocs.
	(bfd_elf_gc_sections): Use link_info_ok.  Pass &link_info_ok
	to elf_gc_smash_unused_vtentry_relocs.
	* libbfd-in.h (_bfd_link_keep_memory): New.
	* linker.c (_bfd_link_keep_memory): New.
	* opncls.c (bfd_alloc): Update alloc_size.
	* bfd-in2.h: Regenerated.
	* libbfd.h: Likewise.

include/

	PR ld/18028
	* bfdlink.h (bfd_link_info): Add cache_size and max_cache_size.

ld/

	PR ld/18028
	* NEWS: Mention --max-cache-size=SIZE.
	* ld.texi: Document --max-cache-size=SIZE.
	* ldlex.h (option_values): Add OPTION_MAX_CACHE_SIZE.
	* ldmain.c: (main): Set link_info.max_cache_size to -1.
	* lexsup.c (ld_options): Add --max-cache-size=SIZE.
	(parse_args): Support OPTION_MAX_CACHE_SIZE.
	* testsuite/ld-bootstrap/bootstrap.exp: Add test for
	--max-cache-size=-1.
 2021-07-08 09:59:28 -07:00
Alan Modra
9193bc4285 Use bool in include 
* bfdlink.h: Replace bfd_boolean with bool throughout.
	* coff/ecoff.h: Likewise.
	* coff/xcoff.h: Likewise.
	* dis-asm.h: Likewise.
	* elf/mmix.h: Likewise.
	* elf/xtensa.h: Likewise.
	* opcode/aarch64.h: Likewise, and FALSE with false, TRUE with true.
	* opcode/arc.h: Likewise.
	* opcode/mips.h: Likewise.
	* opcode/tic6x-opcode-table.h: Likewise.
	* opcode/tic6x.h: Likewise.
 2021-03-31 10:49:23 +10:30
Alan Modra
8ee10e8609 PR27451, -z start_stop_gc 
When --gc-sections is in effect, a reference from a retained section
to __start_SECNAME or __stop_SECNAME causes all input sections named
SECNAME to also be retained, if SECNAME is representable as a C
identifier and either __start_SECNAME or __stop_SECNAME is synthesized
by the linker.  Add an option to disable that feature, effectively
ignoring any relocation that references a synthesized linker defined
__start_ or __stop_ symbol.

	PR 27451
include/
	* bfdlink.h (struct bfd_link_info): Add start_stop_gc.
bfd/
	* elflink.c (_bfd_elf_gc_mark_rsec): Ignore synthesized linker
	defined start/stop symbols when start_stop_gc.
	(bfd_elf_gc_mark_dynamic_ref_symbol): Likewise.
	(bfd_elf_define_start_stop): Don't modify ldscript_def syms.
	* linker.c (bfd_generic_define_start_stop): Likewise.
ld/
	* emultempl/elf.em: Handle -z start-stop-gc and -z nostart-stop-gc.
	* lexsup.c (elf_static_list_options): Display help for them.  Move
	help for -z stack-size to here from elf_shlib_list_options. Add
	help for -z start-stop-visibility and -z undefs.
	* ld.texi: Document -z start-stop-gc and -z nostart-stop-gc.
	* NEWS: Mention -z start-stop-gc.
	* testsuite/ld-gc/start2.s,
	* testsuite/ld-gc/start2.d: New test.
	* testsuite/ld-gc/gc.exp: Run it.
 2021-03-01 17:28:03 +10:30
Alan Modra
89753bbf81 Warn when a script redefines a symbol 
Note that we don't even warn if scripts adjust a symbol as in
ld-elf/var1 and ld-scripts/pr14962.

include/
	* bfdlink.h (struct bfd_link_info): Add warn_multiple_definition.
ld/
	* ldexp.c (exp_fold_tree_1): Warn on script defining a symbol
	defined in an object file.
	* ldmain.c (multiple_definition): Heed info->warn_multiple_definition.
	* testsuite/ld-scripts/defined5.d: Expect a warning.
 2021-02-21 14:28:16 +10:30
Alan Modra
250d07de5c Update year range in copyright notice of binutils files 2021-01-01 10:31:05 +10:30
Alan Modra
c410035d37 constify elfNN_bed 
elfNN_bed was made writable as an expedient means of communicating
ld -z max-page-size and ld -z common-page-size values to BFD linker
code, and even for objcopy to communicate segment alignment between
copy_private_bfd_data, rewrite_elf_program_header and
assign_file_positions_for_load_sections.  Some time later elfNN_bed
elf_osabi was written by gas.  It turns out none of these
modifications to elfNN_bed was necessary, so make it const again.

include/
	* bfdlink.h (struct bfd_link_info): Add maxpagesize and
	commonpagesize.
bfd/
	* elfxx-target.h (elfNN_bed): Constify.
	* bfd.c (bfd_elf_set_pagesize): Delete.
	(bfd_emul_set_maxpagesize, bfd_emul_set_commonpagesize): Delete.
	* elf.c (get_program_header_size): Get commonpagesize from
	link info.
	(_bfd_elf_map_sections_to_segments): Get maxpagesize from link info.
	(assign_file_positions_for_load_sections): Likewise.
	(assign_file_positions_for_non_load_sections): Likewise.
	(rewrite_elf_program_header): Add maxpagesize param.  Set map_p_align.
	(copy_private_bfd_data): Don't call bfd_elf_set_maxpagesize.
	Instead pass maxpagesize to rewrite_elf_program_header.
	* elf32-nds32.c (relax_range_measurement): Add link_info param.
	Get maxpagesize from link_info.  Adjust caller.
	* bfd-in2.h: Regenerate.
gas/
	* config/obj-elf.c (obj_elf_section): Don't set elf_osabi here.
	(obj_elf_type): Likewise.
ld/
	* ld.h (ld_config_type): Delete maxpagesize and commonpagesize.
	* emultempl/elf.em: Use link_info rather than config
	for maxpagesize and commonpagesize.
	* emultempl/ppc32elf.em: Likewise.
	* ldexp.c (fold_binary, fold_name): Likewise.
	* ldemul.c (after_parse_default): Likewise.
	(set_output_arch_default): Don't call bfd_emul_set_maxpagesize
	or bfd_emul_set_commonpagesize.
 2020-12-16 15:17:53 +10:30
Vivek Das Mohapatra
6a0a0dd0cc Handle -z unique/-z nounique in ld 
Add (or suppress) a DT_GNU_FLAGS_1 dynamic section
with a bit flag value of DF_GNU_1_UNIQUE.

bfd/
	* elflink.c (bfd_elf_size_dynamic_sections): Call
	_bfd_elf_add_dynamic_entry to add a DT_GNU_FLAGS_1 section.
include/
	* bfdlink.h (struct bfd_link_info): New field gnu_flags_1.
ld/
	* emultempl/elf.em (gld${EMULATION_NAME}_handle_option):
	Parse -z unique / -z nounique options.
 2020-12-15 18:44:56 +10:30
Nick Alcock
3d16b64e28 bfd, include, ld, binutils, libctf: CTF should use the dynstr/sym 
This is embarrassing.

The whole point of CTF is that it remains intact even after a binary is
stripped, providing a compact mapping from symbols to types for
everything in the externally-visible interface of an ELF object: it has
connections to the symbol table for that purpose, and to the string
table to avoid duplicating symbol names.  So it's a shame that the hooks
I implemented last year served to hook it up to the .symtab and .strtab,
which obviously disappear on strip, leaving any accompanying the CTF
dict containing references to strings (and, soon, symbols) which don't
exist any more because their containing strtab has been vaporized.  The
original Solaris design used .dynsym and .dynstr (well, actually,
.ldynsym, which has more symbols) which do not disappear. So should we.

Thankfully the work we did before serves as guide rails, and adjusting
things to use the .dynstr and .dynsym was fast and easy.  The only
annoyance is that the dynsym is assembled inside elflink.c in a fairly
piecemeal fashion, so that the easiest way to get the symbols out was to
hook in before every call to swap_symbol_out (we also leave in a hook in
front of symbol additions to the .symtab because it seems plausible that
we might want to hook them in future too: for now that hook is unused).
We adjust things so that rather than being offered a whole hash table of
symbols at once, libctf is now given symbols one at a time, with st_name
indexes already resolved and pointing at their final .dynstr offsets:
it's now up to libctf to resolve these to names as needed using the
strtab info we pass it separately.

Some bits might be contentious.  The ctf_new_dynstr callback takes an
elf_internal_sym, and this remains an elf_internal_sym right down
through the generic emulation layers into ldelfgen.  This is no worse
than the elf_sym_strtab we used to pass down, but in the future when we
gain non-ELF CTF symtab support we might want to lower the
elf_internal_sym to some other representation (perhaps a
ctf_link_symbol) in bfd or in ldlang_ctf_new_dynsym.  We rename the
'apply_strsym' hooks to 'acquire_strings' instead, becuse they no longer
have anything to do with symbols.

There are some API changes to pieces of API which are technically public
but actually totally unused by anything and/or unused by anything but ld
so they can change freely: the ctf_link_symbol gains new fields to allow
symbol names to be given as strtab offsets as well as strings, and a
symidx so that the symbol index can be passed in.  ctf_link_shuffle_syms
loses its callback parameter: the idea now is that linkers call the new
ctf_link_add_linker_symbol for every symbol in .dynsym, feed in all the
strtab entries with ctf_link_add_strtab, and then a call to
ctf_link_shuffle_syms will apply both and arrange to use them to reorder
the CTF symtab at CTF serialization time (which is coming in the next
commit).

Inside libctf we have a new preamble flag CTF_F_DYNSTR which is always
set in v3-format CTF dicts from this commit forwards: CTF dicts without
this flag are associated with .strtab like they used to be, so that old
dicts' external strings don't turn to garbage when loaded by new libctf.
Dicts with this flag are associated with .dynstr and .dynsym instead.
(The flag is not the next in sequence because this commit was written
quite late: the missing flags will be filled in by the next commit.)

Tests forthcoming in a later commit in this series.

bfd/ChangeLog
2020-11-20  Nick Alcock  <nick.alcock@oracle.com>

	* elflink.c (elf_finalize_dynstr): Call examine_strtab after
	dynstr finalization.
	(elf_link_swap_symbols_out): Don't call it here.  Call
	ctf_new_symbol before swap_symbol_out.
	(elf_link_output_extsym): Call ctf_new_dynsym before
	swap_symbol_out.
	(bfd_elf_final_link): Likewise.
	* elf.c (swap_out_syms): Pass in bfd_link_info.  Call
	ctf_new_symbol before swap_symbol_out.
	(_bfd_elf_compute_section_file_positions): Adjust.

binutils/ChangeLog
2020-11-20  Nick Alcock  <nick.alcock@oracle.com>

	* readelf.c (dump_section_as_ctf): Use .dynsym and .dynstr, not
	.symtab and .strtab.

include/ChangeLog
2020-11-20  Nick Alcock  <nick.alcock@oracle.com>

	* bfdlink.h (struct elf_sym_strtab): Replace with...
	(struct elf_internal_sym): ... this.
	(struct bfd_link_callbacks) <examine_strtab>: Take only a
	symstrtab argument.
	<ctf_new_symbol>: New.
	<ctf_new_dynsym>: Likewise.
	* ctf-api.h (struct ctf_link_sym) <st_symidx>: New.
	<st_nameidx>: Likewise.
	<st_nameidx_set>: Likewise.
	(ctf_link_iter_symbol_f): Removed.
	(ctf_link_shuffle_syms): Remove most parameters, just takes a
	ctf_dict_t now.
	(ctf_link_add_linker_symbol): New, split from
	ctf_link_shuffle_syms.
	* ctf.h (CTF_F_DYNSTR): New.
	(CTF_F_MAX): Adjust.

ld/ChangeLog
2020-11-20  Nick Alcock  <nick.alcock@oracle.com>

	* ldelfgen.c (struct ctf_strsym_iter_cb_arg): Rename to...
	(struct ctf_strtab_iter_cb_arg): ... this, changing fields:
	<syms>: Remove.
	<symcount>: Remove.
	<symstrtab>: Rename to...
	<strtab>: ... this.
	(ldelf_ctf_strtab_iter_cb): Adjust.
	(ldelf_ctf_symbols_iter_cb): Remove.
	(ldelf_new_dynsym_for_ctf): New, tell libctf about a single
	symbol.
	(ldelf_examine_strtab_for_ctf): Rename to...
	(ldelf_acquire_strings_for_ctf): ... this, only doing the strtab
	portion and not symbols.
	* ldelfgen.h: Adjust declarations accordingly.
	* ldemul.c (ldemul_examine_strtab_for_ctf): Rename to...
	(ldemul_acquire_strings_for_ctf): ... this.
	(ldemul_new_dynsym_for_ctf): New.
	* ldemul.h: Adjust declarations accordingly.
	* ldlang.c (ldlang_ctf_apply_strsym): Rename to...
	(ldlang_ctf_acquire_strings): ... this.
	(ldlang_ctf_new_dynsym): New.
	(lang_write_ctf): Call ldemul_new_dynsym_for_ctf with NULL to do
	the actual symbol shuffle.
	* ldlang.h (struct elf_strtab_hash): Adjust accordingly.
	* ldmain.c (bfd_link_callbacks): Wire up new/renamed callbacks.

libctf/ChangeLog
2020-11-20  Nick Alcock  <nick.alcock@oracle.com>

	* ctf-link.c (ctf_link_shuffle_syms): Adjust.
	(ctf_link_add_linker_symbol): New, unimplemented stub.
	* libctf.ver: Add it.
	* ctf-create.c (ctf_serialize): Set CTF_F_DYNSTR on newly-serialized
	dicts.
	* ctf-open-bfd.c (ctf_bfdopen_ctfsect): Check for the flag: open the
	symtab/strtab if not present, dynsym/dynstr otherwise.
	* ctf-archive.c (ctf_arc_bufpreamble): New, get the preamble from
	some arbitrary member of a CTF archive.
	* ctf-impl.h (ctf_arc_bufpreamble): Declare it.
 2020-11-20 13:34:07 +00:00
H.J. Lu
496afd1705 elf: Add -z unique-symbol to avoid duplicated local symbol names 
The symbol string table in the .symtab section is optional and cosmetic.
The contents of the .symtab section have no impact on run-time execution.
The symbol names in the symbol string table help distinguish addresses at
different locations.  Add a linker option, -z unique-symbol, to avoid
duplicated local symbol names in the symbol string table.

This feature was well received by the livepatch maintainers.  It not only
solves the duplicated local symbol name problem, but also would allow
livepatch to more precisely locate duplicate symbols in general for
patching.

bfd/

	PR ld/26391
	* elflink.c (elf_final_link_info): Add local_hash_table.
	(local_hash_entry): New.
	(local_hash_newfunc): Likewise.
	(elf_link_output_symstrtab): Append ".COUNT" to duplicated local
	symbols.
	(bfd_elf_final_link): Initialize and free local_hash_table for
	"-z unique-symbol".

include/

	PR ld/26391
	* bfdlink.h (bfd_link_info): Add unique_symbol.

ld/

	PR ld/26391
	* NEWS: Mention "-z unique-symbol".
	* emultempl/elf.em (gld${EMULATION_NAME}_handle_option): Handle
	"-z unique-symbol" and "-z nounique-symbol".
	* ld.texi: Document "-z unique-symbol" and "-z nounique-symbol".
	* lexsup.c (elf_static_list_options): Add "-z unique-symbol" and
	"-z nounique-symbol".
	* testsuite/ld-elf/elf.exp: Add PR ld/26391 tests.
	* testsuite/ld-elf/pr26391.nd: New file.
	* testsuite/ld-elf/pr26391.out: Likewise.
	* testsuite/ld-elf/pr26391a.c: Likewise.
	* testsuite/ld-elf/pr26391b.c: Likewise.
	* testsuite/ld-elf/pr26391c.c: Likewise.
	* testsuite/ld-elf/pr26391d.c: Likewise.
 2020-09-12 05:37:43 -07:00
H.J. Lu
0e6a3f07f5 ld: Properly override the IR definition 
We change the previous definition in the IR object to undefweak only
after all LTO symbols have been read.

include/

	PR ld/26262
	PR ld/26267
	* bfdlink.h (bfd_link_info): Add lto_all_symbols_read.

ld/

	PR ld/26262
	PR ld/26267
	* ldlang.c (lang_process): Set lto_all_symbols_read after all
	LTO IR symbols have been read.
	* plugin.c (plugin_notice): Override the IR definition only if
	all LTO IR symbols have been read or the new definition is
	non-weak and the the IR definition is weak
	* testsuite/ld-plugin/lto.exp: Run PR ld/26262 and ld/26267
	tests.
	* testsuite/ld-plugin/pr26262a.c: New file.
	* testsuite/ld-plugin/pr26262b.c: Likewise.
	* testsuite/ld-plugin/pr26262c.c: Likewise.
	* testsuite/ld-plugin/pr26267.err: Likewise.
	* testsuite/ld-plugin/pr26267a.c: Likewise.
	* testsuite/ld-plugin/pr26267b.c: Likewise.
	* testsuite/ld-plugin/pr26267c.c: Likewise.
 2020-07-22 03:49:17 -07:00
Roland McGrath
cae64165f4 gold, ld: Implement -z start-stop-visibility=... option. 
gold/
	Implement -z start-stop-visibility=... option.
	* options.h (class General_options): Handle -z start-stop-visibility=.
	(General_options::start_stop_visibility_enum): New public method.
	(General_options::set_start_stop_visibility_enum): New private method.
	(General_options::start_stop_visibility_enum_): New private member.
	* options.cc (General_options::General_options): Add initializer.
	(General_options::finalize): Set this->start_stop_visibility_enum_
	from string value.
	* layout.cc (Layout::define_section_symbols): Use option setting.

bfd/
	* elflink.c (bfd_elf_define_start_stop): Use start_stop_visibility
	field of bfd_link_info.

include/
	* bfdlink.h (struct bfd_link_info): New field start_stop_visibility.

ld/
	* NEWS: Mention -z start-stop-visibility=... option for ELF.
	* ld.texi (Options): Document -z start-stop-visibility=... option.
	* ldmain.c (main): Initialize link_info.start_stop_visibility.
	* emultempl/elf.em (gld${EMULATION_NAME}_handle_option):
	Parse -z start-stop-visibility=... option.
 2020-06-15 11:45:02 -07:00
H.J. Lu
a6dbf402de ld: Add --warn-textrel and obsolete --warn-shared-textrel 
--warn-shared-textrel and -z text apply to both shared object and PIE.
Add --warn-textrel and obsolete --warn-shared-textrel.  Consolidate
--warn-textrel and -z text/notext/textoff implementation.

bfd/

	PR ld/22909
	* elflink.c (bfd_elf_final_link): Use bfd_link_textrel_check.
	Check bfd_link_dll when issue a DT_TEXTREL warning.
	* elfxx-x86.c (maybe_set_textrel): Likewise.
	(_bfd_x86_elf_size_dynamic_sections): Likewise.

include/

	PR ld/22909
	* bfdlink.h (textrel_check_method): New enum.
	(bfd_link_textrel_check): New.
	(bfd_link_info): Replace warn_shared_textrel and error_textrel
	with textrel_check.

ld/

	PR ld/22909
	* NEWS: Mention --warn-textrel.
	* ld.texi: Update -z text/notext/textoff.  Add --warn-textrel.
	Remove --warn-shared-textrel.
	* ldlex.h (option_values): Rename OPTION_WARN_SHARED_TEXTREL to
	OPTION_WARN_TEXTREL.
	* lexsup.c (ld_options): Add --warn-textrel.  Obsolete
	--warn-shared-textrel.
	(parse_args): Updated.
	(elf_shlib_list_options): Check link_info.textrel_check.
	* emultempl/elf.em: Updated.
	* testsuite/ld-elf/pr19539.d: Replace -z notext with
	--warn-textrel.  Expect a warning.
	* testsuite/ld-i386/warn1.d: Update expected warning.
 2020-05-27 04:54:10 -07:00
Fangrui Song
95a5156812 Unify the behaviour of ld.bfd and ld.gold with respect to warning about unresolved symbol references. (PR 24613) 
PR binutils/24613
include	* bfdlink.h (enum report_method): Delete RM_GENERATE_WARNING and
	RM_GENERATE_ERROR. Add RM_DIAGNOSE.
	(struct bfd_link_info): Add warn_unresolved_syms.

ld	* lexsup.c (parse_args): Change RM_GENERATE_WARNING and
	RM_GENERATE_ERROR to RM_DIAGNOSE.
	* emultempl/aix.em (ld_${EMULATION_NAME}_emulation): Change
	RM_GENERATE_ERROR to RM_DIAGNOSE.
	* emultempl/elf.em (ld_${EMULATION_NAME}_emulation): Likewise.

bfd	* coff-rs6000.c (xcoff_ppc_relocate_section): Change RM_GENERATE_ERROR
	to RM_DIAGNOSE plus a check of warn_unresolved_syms.
	* coff64-rs6000.c (xcoff_ppc_relocate_section): Likewise.
	* elf-bfd.h (_bfd_elf_large_com_section): Likewise.
	* elf32-m32r.c (m32r_elf_relocate_section): Likewise.
	* elf32-score.c (s3_bfd_score_elf_relocate_section): Likewise.
	* elf32-score7.c (s7_bfd_score_elf_relocate_section): Likewise.
	* elf32-sh.c (sh_elf_relocate_section): Likewise.
	* elf32-spu.c (spu_elf_relocate_section): Likewise.
	* elf64-hppa.c (elf64_hppa_relocate_section): Likewise.
	* elflink.c (elf_link_output_extsym): Likewise.
	* elfxx-mips.c (mips_elf_calculate_relocation): Likewise.
 2020-04-15 14:25:08 +01:00
Christophe Lyon
abf874aafe Add support for non-contiguous memory regions 
2020-01-06  Christophe Lyon  <christophe.lyon@linaro.org>

	bfd/
	* bfd-in2.h: Regenerate.
	* section.c (asection): Add already_assigned field.
	(BFD_FAKE_SECTION): Add default initializer for it.
	* ecoff.c (bfd_debug_section): Initialize already_assigned field.
	* elf32-arm.c (arm_build_one_stub): Add support for
	non_contiguous_regions.
	* elf32-csky.c (csky_build_one_stub): Likewise.
	* elf32-hppa.c (hppa_build_one_stub): Likewise.
	* elf32-m68hc11.c (m68hc11_elf_build_one_stub): Likewise.
	* elf32-m68hc12.c (m68hc12_elf_build_one_stub): Likewise.
	* elf32-metag.c (metag_build_one_stub): Likewise.
	* elf32-nios2.c (nios2_build_one_stub): Likewise.
	* elf64-ppc.c (ppc_build_one_stub): Likewise.
	(ppc_size_one_stub): Likewise.
	* elfnn-aarch64.c (aarch64_build_one_stub): Likewise.
	* elflink.c (elf_link_input_bfd): Likewise.

	include/
	* bfdlink.h (bfd_link_info): Add non_contiguous_regions and
	non_contiguous_regions_warnings fields.

	ld/
	* ldlang.c (lang_add_section): Add support for
	non_contiguous_regions.
	(size_input_section): Likewise.
	(lang_size_sections_1): Likewise.
	(process_insert_statements): Likewise.
	* ldlex.h (option_values): Add OPTION_NON_CONTIGUOUS_REGIONS and
	OPTION_NON_CONTIGUOUS_REGIONS_WARNINGS.
	* lexsup.c (ld_options): Add entries for
	--enable-non-contiguous-regions and
	--enable-non-contiguous-regions-warnings.
	(parse_args): Handle it.
	* NEWS: Add --enable-non-contiguous-regions and
	--enable-non-contiguous-regions-warnings.
	* ld.texi: Add --enable-non-contiguous-regions and
	--enable-non-contiguous-regions-warnings documentation.
	* emultempl/armelf.em (elf32_arm_add_stub_section): Add
	SEC_LINKER_CREATED flag.
	* emultempl/xtensaelf.em (ld_build_required_section_dependence):
	Emit an error when --enable-non-contiguous-regions is used.
	* testsuite/ld-elf/non-contiguous.d: New.
	* testsuite/ld-elf/non-contiguous.ld: New.
	* testsuite/ld-elf/non-contiguous.s: New.
	* testsuite/ld-arm/arm-elf.exp: Run the new tests.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm.s: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm.ld: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm2.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm3.ld: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm3.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm3.ld: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm4.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm4.ld: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm5.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm5.ld: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm6.d: New.
	* testsuite/ld-arm/arm-elf/non-contiguous-arm6.ld: New.
	* testsuite/ld-powerpc/powerpc.exp: Run new tests.
	* testsuite/ld-powerpc/non-contiguous-powerpc.d: New.
	* testsuite/ld-powerpc/non-contiguous-powerpc.ld: New.
	* testsuite/ld-powerpc/non-contiguous-powerpc.sd: New.
	* testsuite/ld-powerpc/non-contiguous-powerpc64.d: New.
 2020-03-13 14:44:45 +00:00
Christian Eggers
666318230c Fix several mix up between octets and bytes in ELF program headers 
Fixes additional locations not handled in the first patch.

When converting between addresses in ELF headers [octets] and bfd
LMA/VMA [bytes], the number of octets per byte needs to be incorporated.

include/
	* bfdlink.h (struct bfd_link_order): Add unit (bytes/octets) to
	offset and size members.
	* elf/internal.h (struct elf_internal_phdr): Likewise for
	p_align member.
	(struct elf_segment_map): Likewise for p_paddr and p_size
	members
bfd/
	* bfd.c (bfd_record_phdr): New local "opb".  Fix assignment of
	"p_paddr" from "at".
	* elfcode.h (bfd_from_remote_memory): Add units to several
	parameters.  New local "opb".  Fix usage of p_align.  Fix
	calculation of "localbase" from "ehdr_vma" and "p_vaddr".  Fix
	call of target_read_memory.
	* elflink.c (elf_fixup_link_order): Fix scope of "s" local.  Fix
	calculation of "offset" and "output_offset".
	(bfd_elf_final_link): New local "opb".  Fix calculation of "size"
	from "offset" and fix calculation of "end" from "vma+size".  Fix
	comparison between "sh_addr" and "vma"/"output_offset".
	(bfd_elf_discard_info): Fix calculation of "eh_alignment".
	* elf-bfd.h (struct elf_link_hash_table): Add unit to tls_size
	member.
	* elf.c (_bfd_elf_map_sections_to_segments): Add unit (bytes/
	octets) to "wrap_to2 and "phdr_size" locals.  Fix calculation of
	"wrap_to" value.  Add unit (bytes) to phdr_lma variable.  Fix
	assignment of p_paddr from phdr_lma.  Fix comparison between
	"lma+size" and "next->lma".
	(elf_sort_segments): Fix assignment from p_paddr to lma.
	(assign_file_positions_for_load_sections): Add unit (bytes) to
	local "align".  Fix calculation of local "off_adjust".  Fix
	calculation of local "filehdr_vaddr".
	(assign_file_positions_for_non_load_sections): New local "opb".
	Fix calculation of "end" from "p_size". Fix comparison between
	"vma+SECTION_SIZE" and "start".  Fix calculation of "p_memsz"
	from "end" and "p_vaddr".
	(rewrite_elf_program_header): Fix comparison between p_vaddr and
	vma.  Fix assignment to p_paddr from lma.  Fix comparison between
	p_paddr and lma.  Fix assignment to p_paddr from lma.
	* merge.c (sec_merge_emit): New local "opb". Convert
	"alignment_power" to octets.
	(_bfd_add_merge_section): New locals "alignment_power" and
	"opb".  Fix comparison between "alignment_power" and
	"sizeof(align)".
	(_bfd_merge_sections): New local "opb".  Divide size by opb
	before checking align mask.
 2020-03-13 15:48:01 +10:30
Alan Modra
b3adc24a07 Update year range in copyright notice of binutils files 2020-01-01 18:42:54 +10:30
Alan Modra
22216541c1 PR13616, linker should pad executable sections with nops, not zeros 
This implements padding of orphan executable sections for PowerPC.
Of course, the simple implementation of bfd_arch_ppc_nop_fill and
removing the NOP definition didn't work, with powerpc64 hitting a
testsuite failure linking to S-records.  That's because the srec
target is BFD_ENDIAN_UNKNOWN so the test of bfd_big_endian (abfd) in
default_data_link_order therefore returned false, resulting in a
little-endian nop pattern.  The rest of the patch fixes that problem
by adding a new field to bfd_link_info that can be used to determine
actual endianness on targets like srec.

	PR 13616
include/
	* bfdlink.h (struct bfd_link_info <big_endian>): New field.
bfd/
	* cpu-powerpc.c (bfd_arch_ppc_nop_fill): New function, use it
	for all ppc arch info.
	* linker.c (default_data_link_order): Pass info->big_endian to
	arch_info->fill function.
ld/
	* emulparams/elf64lppc.sh (NOP): Don't define.
	* emulparams/elf64ppc.sh (NOP): Don't define.
	* ldwrite.c (build_link_order): Use link_info.big_endian.  Move
	code determining endian to use for data_statement to..
	* ldemul.c (after_open_default): ..here.  Set link_info.big_endian.
 2019-10-16 23:07:27 +10:30
Nick Alcock
1ff6de0312 bfd, ld: add CTF section linking 
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.
 2019-10-03 17:04:56 +01:00
Alan Modra
640197ac27 linker bfd.h tidy 
bfd/
	* bfd-in.h (bfd_symbol, bfd_section_already_linked),
	(bfd_elf_version_tree): Delete forward declarations.
	Move other forward decls and remaining elf function decl later.
	(bfd_section_already_linked_table_init),
	(bfd_section_already_linked_table_free),
	(_bfd_handle_already_linked, _bfd_nearby_section),
	(_bfd_fix_excluded_sec_syms): Move to bfdlink.h.
include/
	* bfdlink.h (struct bfd_section_already_linked): Forward declare.
	(bfd_section_already_linked_table_init),
	(bfd_section_already_linked_table_free),
	(_bfd_handle_already_linked, _bfd_nearby_section),
	(_bfd_fix_excluded_sec_syms): Declare.
 2019-09-23 10:27:22 +09:30
Alan Modra
0b4453c791 elf bfd.h tidy 
bfd/
	* bfd-in.h (enum notice_asneeded_action): Move to bfdlink.h.
	Move most other elf declarations..
	* elf-bfd.h: ..to here.
	* bfd-in2.h: Regenerate.
include/
	* bfdlink.h (enum notice_asneeded_action): Define.
ld/
	* deffilep.y: Include bfdlink.h.
	* ldelf.c: Likewise.
	* ldelfgen.c: Likewise.
	* ldver.c: Likewise.
	* mri.c: Likewise.
	* emultempl/irix.em: Don't include ld.h, ldmain.h, libiberty.h.
	Comment.
 2019-09-23 10:27:22 +09:30
H.J. Lu
5b9c07b278 x86: Move x86-specific linker options to elf_linker_x86_params 
Remove x86-specific linker options from bfd_link_info and put them in
elf_linker_x86_params.  Add _bfd_elf_linker_x86_set_options to pass
x86-specific linker options from ld to bfd.

bfd/

	* elf-linker-x86.h: New file.
	* elf32-i386.c (elf_i386_convert_load_reloc): Use htab->params
	to get x86-specific linker options.
	* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Likewise.
	(elf_x86_64_check_relocs): Likewise.
	(elf_x86_64_relocate_section): Likewise.
	(elf_x86_64_link_setup_gnu_properties): Likewise.
	* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Likewise.
	(_bfd_x86_elf_link_setup_gnu_properties): Likewise.
	(_bfd_elf_linker_x86_set_options): New function.
	* elfxx-x86.h: Include "elf-linker-x86.h".
	(elf_x86_link_hash_table): Add params.

include/

	* bfdlink.h (bfd_link_info): Remove x86-specific linker options.

ld/

	* Makefile.am (ELF_X86_DEPS): Add $(srcdir)/emultempl/elf-x86.em.
	(eelf_i386_sol2.c): Also depend on
	$(srcdir)/emultempl/solaris2-x86.em.
	(eelf_x86_64_sol2.c): Likewise.
	* Makefile.in: Regenerated.
	* emulparams/call_nop.sh: Set x86-specific linker options via
	params.
	* emulparams/cet.sh: Likewise.
	* emulparams/reloc_overflow.sh: Likewise.
	* emulparams/elf32_x86_64.sh (EXTRA_EM_FILE): New.  Set to
	"elf-x86".
	* emulparams/elf_i386.sh: Likewise.
	* emulparams/elf_i386_be.sh: Likewise.
	* emulparams/elf_i386_chaos.sh: Likewise.
	* emulparams/elf_i386_ldso.sh: Likewise.
	* emulparams/elf_i386_vxworks.sh: Likewise.
	* emulparams/elf_iamcu.sh: Likewise.
	* emulparams/elf_k1om.sh: Likewise.
	* emulparams/elf_l1om.sh: Likewise.
	* emulparams/elf_x86_64.sh: Likewise.
	* emulparams/elf_i386_sol2.sh (EXTRA_EM_FILE): Changed to
	"solaris2-x86".
	* emulparams/elf_x86_64_sol2.sh: Likewise.
	* emultempl/elf-x86.em: New file.
	* emultempl/solaris2-x86.em: Likewise.
	* emultempl/elf32.em (gld${EMULATION_NAME}_before_parse): Don't
	set link_info.call_nop_byte.
 2019-04-06 07:25:31 -07:00
Alan Modra
827041555a Update year range in copyright notice of binutils files 2019-01-01 22:06:53 +10:30
H.J. Lu
d2ef37ebd9 elf: Report property change when merging properties 
With merging properties, report property change in linker map file, like

Merging program properties

Removed property 0xc0010000 to merge /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crt1.o (0x0) and /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crti.o (0x0)
Removed property 0xc0000002 to merge /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crt1.o (0x3) and x.o (not found)
Removed property 0xc0000000 to merge /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crt1.o (not found) and /usr/lib64/libc_nonshared.a(elf-init.oS) (0x0)
Removed property 0xc0000001 to merge /usr/lib/gcc/x86_64-redhat-linux/8/../../../../lib64/crt1.o (not found) and /usr/lib64/libc_nonshared.a(elf-init.oS) (0x0)

bfd/

	* elf-properties.c (elf_find_and_remove_property): Add a
	bfd_boolean argument to indicate if the property should be
	removed.
	(elf_merge_gnu_property_list): Updated.  Report
	property change in linker map file.
	(elf_get_gnu_property_section_size): Skip property_remove
	properties.
	(elf_write_gnu_properties): Likewise.
	(_bfd_elf_link_setup_gnu_properties): Report property merge
	in linker map file.  Pass abfd to elf_merge_gnu_property_list.

include/

	* bfdlink.h (bfd_link_info): Add has_map_file.

ld/

	* NEWS: Updated for property change report.
	* ld.texi: Document property change report.
	* ldmain.c (main): Set link_info.has_map_file to TRUE when
	linker map file is used.
	* testsuite/ld-scripts/rgn-over1.d: Updated.
	* testsuite/ld-scripts/rgn-over2.d: Likewise.
	* testsuite/ld-scripts/rgn-over3.d: Likewise.
	* testsuite/ld-scripts/rgn-over4.d: Likewise.
	* testsuite/ld-scripts/rgn-over5.d: Likewise.
	* testsuite/ld-scripts/rgn-over6.d: Likewise.
	* testsuite/ld-scripts/rgn-over7.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1a-x32.d: Check linker map
	file.
	* testsuite/ld-x86-64/property-x86-ibt1a.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1a.map: New file.
 2018-12-07 08:30:43 -08:00
Alan Modra
64029e9368 Separate header PT_LOAD for -z separate-code 
This patch, along with previous patches in the series, supports
putting the ELF file header and program headers in a PT_LOAD without
sections.

Logic governing whether headers a loaded has changed a little:  The
primary reason to include headers is now the presence of
SIZEOF_HEADERS in a linker script.  However, to support scripts that
may have reserved space for headers by hand, we continue to add
headers whenever the first section address is past the end of headers
modulo page size.

include/
	* bfdlink.h (struct bfd_link_info): Add load_phdrs field.
bfd/
	* elf-nacl.c (nacl_modify_segment_map): Cope with header PT_LOAD
	lacking sections.
	* elf.c (_bfd_elf_map_sections_to_segments): Assume file and
	program headers are required when info->load_phdrs.  Reorganize
	code handling program headers.  Generate a mapping without
	sections just for file and program headers when -z separate-code
	would indicate they should be on a different page to the first
	section.
ld/
	* ldexp.c (fold_name <SIZEOF_HEADERS>): Set link_info.load_phdrs.
	* testsuite/ld-elf/loadaddr1.d: Pass -z noseparate-code.
	* testsuite/ld-elf/loadaddr2.d: Likewise.
	* testsuite/ld-i386/vxworks2.sd: Adjust expected output.
	* testsuite/ld-powerpc/vxworks2.sd: Likewise.
	* testsuite/ld-elf/overlay.d: Remove spu xfail.
	* testsuite/ld-spu/ovl.lnk: Don't use SIZEOF_HEADERS.
	* testsuite/ld-tic6x/dsbt-be.ld: Likewise.
	* testsuite/ld-tic6x/dsbt-inrange.ld: Likewise.
	* testsuite/ld-tic6x/dsbt-overflow.ld: Likewise.
	* testsuite/ld-tic6x/dsbt.ld: Likewise.
 2018-10-08 20:26:08 +10:30
Maciej W. Rozycki
d5c928c053 LD: Export relative-from-absolute symbol marking to BFD 
It is usually possible to tell absolute and ordinary symbols apart in
BFD throughout the link, by checking whether the section that owns the
symbol is absolute or not.

That however does not work for ordinary symbols defined in a linker
script outside an output section statement.  Initially such symbols are
entered into to the link hash as absolute symbols, owned by the absolute
section.  A flag is set in the internal linker expression defining such
symbols to tell the linker to convert them to section-relative ones in
the final phase of the link.  That flag is however not accessible to BFD
linker code, including BFD target code in particular.

Add a flag to the link hash then to copy the information held in the
linker expression.  Define a macro, `bfd_is_abs_symbol', for BFD code to
use where determining whether a symbol is absolute or ordinary is
required before the final link phase.

This macro will correctly identify the special `__ehdr_start' symbol as
ordinary throughout link, for example, even though early on it will be
assigned to the absolute section.  Of course this does not let BFD code
identify what the symbol's ultimate section will be before the final
link phase has converted this symbol (in `update_definedness').

	include/
	* bfdlink.h (bfd_link_hash_entry): Add `rel_from_abs' member.

	bfd/
	* linker.c (bfd_is_abs_symbol): New macro.
	* bfd-in2.h: Regenerate.

	ld/
	* ldexp.c (exp_fold_tree_1) <etree_assign, etree_provide>
	<etree_provided>: Copy expression's `rel_from_abs' flag to the
	link hash.
 2018-07-17 20:04:53 +01:00
Michael Eager
3f0a5f17d7 [MicroBlaze] PIC data text relative 
Andrew Sadek <andrew.sadek.se@gmail.com>

A new implemented feature in GCC Microblaze that allows Position
Independent Code to run using Data Text Relative addressing instead
of using Global Offset Table.

Its aim was to make 'PIC' more efficient and flexible as elf size
excess performance overhead were noticed when using GOT due to the
indirect addressing.

include/ChangeLog:
	* bfdlink.h (Add flag): Add new flag @ 'bfd_link_info' struct.
	* elf/microblaze.h (Add 3 new relocations):
	R_MICROBLAZE_TEXTPCREL_64, R_MICROBLAZE_TEXTREL_64
	and R_MICROBLAZE_TEXTREL_32_LO for relax function.
bfd/ChangeLog:
	* bfd/reloc.c (2 new BFD relocations):
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL &
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL
	* bfd/bfd-in2.h: Regenerate
	* bfd/libbfd.h: Regenerate
	* bfd/elf32-microblaze.c (Handle new relocs): define 'HOWTO' of 3
	new relocs and handle them in both relocate and relax functions.
	(microblaze_elf_reloc_type_lookup): add mapping between for new
	bfd relocs.
	(microblaze_elf_relocate_section): Handle new relocs in case of
	elf relocation.
	(microblaze_elf_relax_section): Handle new relocs for elf relaxation.
gas/ChangeLog:
	* gas/config/tc-microblaze.c (Handle new relocs directives in
	assembler): Handle new relocs from compiler output.
	(imm_types): add new imm types for data text relative addressing
	TEXT_OFFSET, TEXT_PC_OFFSET
	(md_convert_frag): conversion for BFD_RELOC_MICROBLAZE_64_TEXTPCREL,
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL
	(md_apply_fix): apply fix for BFD_RELOC_MICROBLAZE_64_TEXTPCREL,
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL
	(md_estimate_size_before_relax): estimate size for
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL,
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL
	(tc_gen_reloc): generate relocations for
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL,
	BFD_RELOC_MICROBLAZE_64_TEXTPCREL
ld/ChangeLog:
	* ld/lexsup.c (Add 2 ld options):
	(ld_options): add disable-multiple-abs-defs @ 'ld_options' array
	(parse_args): parse new option and pass flag to 'link_info' struct.
	* ld/ldlex.h (Add enum): add new enum @ 'option_values' enum.
	* ld/ld.texinfo (Add new option): Add description for
	'disable-multiple-abs-defs'
	* ld/main.c: Initialize flags with false @ 'main'. Handle
	disable-multiple-abs-defs @ 'mutiple_definition'.
 2018-04-17 14:47:13 -07:00
H.J. Lu
47acac12c8 ld: Add "-z separate-code" option to ELF linker 
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}.
 2018-01-11 19:01:52 -08:00
Alan Modra
219d1afa89 Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
H.J. Lu
a4819f54c0 Treat common symbol as undefined for --no-define-common 
When --no-define-common is used to build shared library, treat common
symbol as undefined so that common symbols that are referenced from a
shared library to be assigned addresses only in the main program.  This
eliminates the unused duplicate space in the shared library, and also
prevents any possible confusion over resolving to the wrong duplicate
when there are many dynamic modules with specialized search paths for
runtime symbol resolution.

--no-define-common is only allowed when building a shared library.

bfd/

	PR ld/21903:
	* elflink.c (elf_link_add_object_symbols): Treat common symbol
	as undefined for --no-define-common.

include/

	PR ld/21903:
	* bfdlink.h (bfd_link_info): Add inhibit_common_definition.

ld/

	PR ld/21903:
	* ld.h (command_line): Remove inhibit_common_definition.
	* ldgram.y: Replace command_line.inhibit_common_definition with
	link_info.inhibit_common_definition.
	* ldlang.c (lang_common): Likewise.
	* lexsup.c (parse_args): Likewise.
	* ldmain.c (main): Only allow --no-define-common with -shared.
	* testsuite/ld-elf/pr21903.s: New file.
	* testsuite/ld-elf/pr21903a.d: Likewise.
	* testsuite/ld-elf/pr21903b.d: Likewise.
	* testsuite/ld-elf/pr21903c.d: Likewise.
	* testsuite/ld-elf/pr21903d.d: Likewise.
	* testsuite/ld-elf/pr21903e.d: Likewise.
 2017-08-06 08:19:04 -07:00
H.J. Lu
48580982ef x86: Support Intel Shadow Stack with SHSTK property 
To support Intel Shadow Stack (SHSTK) in Intel Control-flow Enforcement
Technology (CET) instructions:

https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf

 #define GNU_PROPERTY_X86_FEATURE_1_SHSTK (1U << 1)

is added to GNU program properties to indicate that all executable sections
are compatible with SHSTK where return address popped from shadow stack
always matches return address popped from normal stack.

GNU_PROPERTY_X86_FEATURE_1_SHSTK is set on output only if it is set on all
relocatable inputs.

bfd/

	* elf32-i386.c (elf_i386_merge_gnu_properties): If info->shstk
	is set, turn on GNU_PROPERTY_X86_FEATURE_1_SHSTK.
	(elf_i386_link_setup_gnu_properties): If info->shstk is set,
	turn on GNU_PROPERTY_X86_FEATURE_1_IBT.
	* elf64-x86-64.c (elf_x86_64_merge_gnu_properties): If
	info->shstk is set, turn on GNU_PROPERTY_X86_FEATURE_1_SHSTK.
	(elf_x86_64_link_setup_gnu_properties): If info->shstk is set,
	turn on GNU_PROPERTY_X86_FEATURE_1_IBT.

binutils/

	* readelf.c (decode_x86_feature): Decode
	GNU_PROPERTY_X86_FEATURE_1_SHSTK.
	* testsuite/binutils-all/i386/shstk.d: New file.
	* testsuite/binutils-all/i386/shstk.s: Likewise.
	* testsuite/binutils-all/x86-64/shstk-x32.d: Likewise.
	* testsuite/binutils-all/x86-64/shstk.d: Likewise.
	* testsuite/binutils-all/x86-64/shstk.s: Likewise.

include/

	* bfdlink.h (bfd_link_info): Add shstk.
	* elf/common.h (GNU_PROPERTY_X86_FEATURE_1_SHSTK): New.

ld/

	* NEWS: Mention -z shstk and GNU_PROPERTY_X86_FEATURE_1_SHSTK.
	* emulparams/cet.sh (PARSE_AND_LIST_OPTIONS_CET): Add "-z shstk".
	(PARSE_AND_LIST_ARGS_CASE_Z_CET): Support "-z shstk".
	* ld.texinfo: Document -z shstk.
	* testsuite/ld-i386/i386.exp: Run SHSTK tests.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-i386/property-x86-shstk.s: New file.
	* testsuite/ld-i386/property-x86-shstk1a.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk1b.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk2.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk3a.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk3b.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk4.d: Likewise.
	* testsuite/ld-i386/property-x86-shstk5.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk.s: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk1a-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk1a.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk1b-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk1b.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk2-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk2.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk3a-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk3a.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk3b-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk3b.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk4-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk4.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk5-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-shstk5.d: Likewise.
 2017-06-22 05:50:31 -07:00
H.J. Lu
ee2fdd6f36 x86: Support Intel IBT with IBT property and IBT-enable PLT 
To support IBT in Intel Control-flow Enforcement Technology (CET)
instructions:

https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf

 #define GNU_PROPERTY_X86_FEATURE_1_AND 0xc0000002

 #define GNU_PROPERTY_X86_FEATURE_1_IBT (1U << 0)

are added to GNU program properties to indicate that all executable
sections are compatible with IBT when ENDBR instruction starts each
valid target where an indirect branch instruction can land.

GNU_PROPERTY_X86_FEATURE_1_IBT is set on output only if it is set on
all relocatable inputs.

The followings changes are made to the Procedure Linkage Table (PLT):

1. For 64-bit x86-64,  PLT is changed to

PLT0:  push       GOT[1]
       bnd jmp    *GOT[2]
       nop
...
PLTn:  endbr64
       push       namen_reloc_index
       bnd jmp    PLT0

together with the second PLT section:

PLTn:  endbr64
       bnd jmp   *GOT[namen_index]
       nop

BND prefix is also added so that IBT-enabled PLT is compatible with MPX.

2. For 32-bit x86-64 (x32) and i386,  PLT is changed to

PLT0:  push       GOT[1]
       jmp        *GOT[2]
       nop
...
PLTn:  endbr64                                 # endbr32 for i386.
       push       namen_reloc_index
       jmp        PLT0

together with the second PLT section:

PLTn:  endbr64                                 # endbr32 for i386.
       jmp       *GOT[namen_index]
       nop

BND prefix isn't used since MPX isn't supported on x32 and BND registers
aren't used in parameter passing on i386.

GOT is an array of addresses.  Initially, GOT[namen_index] is filled
with the address of the ENDBR instruction of the corresponding entry
in the first PLT section.  The function, namen, is called via the
ENDBR instruction in the second PLT entry.  GOT[namen_index] is updated
to the actual address of the function, namen, at run-time.

2 linker command line options are added:

1. -z ibtplt: Generate IBT-enabled PLT.
2. -z ibt: Generate GNU_PROPERTY_X86_FEATURE_1_IBT in GNU program
properties as well as IBT-enabled PLT.

bfd/

	* elf32-i386.c (elf_i386_lazy_ibt_plt0_entry): New.
	(elf_i386_lazy_ibt_plt_entry): Likewise.
	(elf_i386_pic_lazy_ibt_plt0_entry): Likewise.
	(elf_i386_non_lazy_ibt_plt_entry): Likewise.
	(elf_i386_pic_non_lazy_ibt_plt_entry): Likewise.
	(elf_i386_eh_frame_lazy_ibt_plt): Likewise.
	(elf_i386_lazy_plt_layout): Likewise.
	(elf_i386_non_lazy_plt_layout): Likewise.
	(elf_i386_link_hash_entry): Add plt_second.
	(elf_i386_link_hash_table): Add plt_second and
	plt_second_eh_frame.
	(elf_i386_allocate_dynrelocs): Use the second PLT if needed.
	(elf_i386_size_dynamic_sections): Use .plt.got unwind info for
	the second PLT.  Check the second PLT.
	(elf_i386_relocate_section): Use the second PLT to resolve
	PLT reference if needed.
	(elf_i386_finish_dynamic_symbol): Fill and use the second PLT if
	needed.
	(elf_i386_finish_dynamic_sections): Set sh_entsize on the
	second PLT.  Generate unwind info for the second PLT.
	(elf_i386_plt_type): Add plt_second.
	(elf_i386_get_synthetic_symtab): Support the second PLT.
	(elf_i386_parse_gnu_properties): Support
	GNU_PROPERTY_X86_FEATURE_1_AND.
	(elf_i386_merge_gnu_properties): Support
	GNU_PROPERTY_X86_FEATURE_1_AND.  If info->ibt is set, turn
	on GNU_PROPERTY_X86_FEATURE_1_IBT
	(elf_i386_link_setup_gnu_properties): If info->ibt is set,
	turn on GNU_PROPERTY_X86_FEATURE_1_IBT.  Use IBT-enabled PLT
	for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
	is set on all relocatable inputs.
	* elf64-x86-64.c (elf_x86_64_lazy_ibt_plt_entry): New.
	(elf_x32_lazy_ibt_plt_entry): Likewise.
	(elf_x86_64_non_lazy_ibt_plt_entry): Likewise.
	(elf_x32_non_lazy_ibt_plt_entry): Likewise.
	(elf_x86_64_eh_frame_lazy_ibt_plt): Likewise.
	(elf_x32_eh_frame_lazy_ibt_plt): Likewise.
	(elf_x86_64_lazy_ibt_plt): Likewise.
	(elf_x32_lazy_ibt_plt): Likewise.
	(elf_x86_64_non_lazy_ibt_plt): Likewise.
	(elf_x32_non_lazy_ibt_plt): Likewise.
	(elf_x86_64_get_synthetic_symtab): Support the second PLT.
	(elf_x86_64_parse_gnu_properties): Support
	GNU_PROPERTY_X86_FEATURE_1_AND.
	(elf_x86_64_merge_gnu_properties): Support
	GNU_PROPERTY_X86_FEATURE_1_AND.  If info->ibt is set, turn
	on GNU_PROPERTY_X86_FEATURE_1_IBT
	(elf_x86_64_link_setup_gnu_properties): If info->ibt is set,
	turn on GNU_PROPERTY_X86_FEATURE_1_IBT.  Use IBT-enabled PLT
	for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
	is set on all relocatable inputs.

binutils/

	* readelf.c (decode_x86_feature): New.
	(print_gnu_property_note): Call decode_x86_feature on
	GNU_PROPERTY_X86_FEATURE_1_AND.
	* testsuite/binutils-all/i386/empty.d: New file.
	* testsuite/binutils-all/i386/empty.s: Likewise.
	* testsuite/binutils-all/i386/ibt.d: Likewise.
	* testsuite/binutils-all/i386/ibt.s: Likewise.
	* testsuite/binutils-all/x86-64/empty-x32.d: Likewise.
	* testsuite/binutils-all/x86-64/empty.d: Likewise.
	* testsuite/binutils-all/x86-64/empty.s: Likewise.
	* testsuite/binutils-all/x86-64/ibt-x32.d: Likewise.
	* testsuite/binutils-all/x86-64/ibt.d: Likewise.
	* testsuite/binutils-all/x86-64/ibt.s: Likewise.

include/

	* bfdlink.h (bfd_link_info): Add ibtplt and ibt.
	* elf/common.h (GNU_PROPERTY_X86_FEATURE_1_AND): New.
	(GNU_PROPERTY_X86_FEATURE_1_IBT): Likewise.

ld/

	* Makefile.am (ELF_X86_DEPS): Add $(srcdir)/emulparams/cet.sh.
	* Makefile.in: Regenerated.
	* NEWS: Mention GNU_PROPERTY_X86_FEATURE_1_IBT, -z ibtplt
	and -z ibt.
	* emulparams/cet.sh: New file.
	* testsuite/ld-i386/ibt-plt-1.d: Likewise.
	* testsuite/ld-i386/ibt-plt-1.s: Likewise.
	* testsuite/ld-i386/ibt-plt-2.s: Likewise.
	* testsuite/ld-i386/ibt-plt-2a.d: Likewise.
	* testsuite/ld-i386/ibt-plt-2b.d: Likewise.
	* testsuite/ld-i386/ibt-plt-2c.d: Likewise.
	* testsuite/ld-i386/ibt-plt-2d.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3.s: Likewise.
	* testsuite/ld-i386/ibt-plt-3a.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3b.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3c.d: Likewise.
	* testsuite/ld-i386/ibt-plt-3d.d: Likewise.
	* testsuite/ld-i386/plt-main-ibt.dd: Likewise.
	* testsuite/ld-i386/plt-pie-ibt.dd: Likewise.
	* testsuite/ld-i386/property-x86-empty.s: Likewise.
	* testsuite/ld-i386/property-x86-ibt.s: Likewise.
	* testsuite/ld-i386/property-x86-ibt1a.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt1b.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt2.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt3a.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt3b.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt4.d: Likewise.
	* testsuite/ld-i386/property-x86-ibt5.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-1-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-1.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-1.s: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2.s: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2a-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2a.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2b-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2b.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2c-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2d-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-2d.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3.s: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3a-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3a.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3b-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3b.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3c-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3c.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3d-x32.d: Likewise.
	* testsuite/ld-x86-64/ibt-plt-3d.d: Likewise.
	* testsuite/ld-x86-64/plt-main-ibt-now.rd: Likewise.
	* testsuite/ld-x86-64/plt-main-ibt-x32.dd: Likewise.
	* testsuite/ld-x86-64/plt-main-ibt.dd: Likewise.
	* testsuite/ld-x86-64/property-x86-empty.s: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt.s: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1a-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1a.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1b-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt1b.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt2-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt2.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt3a-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt3a.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt3b-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt3b.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt4-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt4.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt5-x32.d: Likewise.
	* testsuite/ld-x86-64/property-x86-ibt5.d: Likewise.
	* emulparams/elf32_x86_64.sh: Source emulparams/cet.sh.
	(TINY_READONLY_SECTION): Add .plt.sec.
	* emulparams/elf_i386.sh: Likewise.
	* emulparams/elf_x86_64.sh: Source emulparams/cet.sh.
	* ld.texinfo: Document -z ibtplt and -z ibt.
	* testsuite/ld-i386/i386.exp: Run IBT and IBT PLT tests.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-x86-64/pr21481b.S (check): Updated for x32.
 2017-06-22 05:44:53 -07:00
Alan Modra
7dba9362c1 Rewrite __start and __stop symbol handling 
This arranges for __start and __stop symbols to be defined before
garbage collection, for all target formats.  That should allow the
COFF and PE --gc-sections to keep a singleton orphan input section,
a feature lost by 2017-06-13 commit cbd0eecf26.  The fancier ELF
treatment of keeping all input sections associated with a __start or
__stop symbol, from 2015-10-23 commit 1cce69b9dc, is retained.

.startof. and .sizeof. symbols are deliberately not defined before
garbage collection, so these won't affect garbage collection of
sections.

The patch also ensures __start, __stop, .startof. and .sizeof. symbols
are defined before target size_dynamic_sections is called, albeit
with a preliminary value, so that target code doesn't need to cope
with a symbol changing from undefined at size_dynamic_sections to
defined at relocate_section.

Also, a number of problems with the testcases have been fixed.

	PR ld/20022
	PR ld/21557
	PR ld/21562
	PR ld/21571
include/
	* bfdlink.h (struct bfd_link_hash_entry): Delete undef.section.
bfd/
	* targets.c (struct bfd_target): Add _bfd_define_start_stop.
	(BFD_JUMP_TABLE_LINK): Likewise.
	* elf-bfd.h (bfd_elf_define_start_stop): Declare.
	* elflink.c (_bfd_elf_gc_mark_rsec): Update comment.
	(bfd_elf_define_start_stop): New function.
	* linker.c (bfd_generic_define_start_stop): New function.
	* coff64-rs6000.c (rs6000_xcoff64_vec, rs6000_xcoff64_aix_vec): Init
	new field.
	* aout-adobe.c (aout_32_bfd_define_start_stop): Define.
	* aout-target.h (MY_bfd_define_start_stop): Define.
	* aout-tic30.c (MY_bfd_define_start_stop): Define.
	* binary.c (binary_bfd_define_start_stop): Define.
	* bout.c (b_out_bfd_define_start_stop): Define.
	* coff-alpha.c (_bfd_ecoff_bfd_define_start_stop): Define.
	* coff-mips.c (_bfd_ecoff_bfd_define_start_stop): Define.
	* coff-rs6000.c (_bfd_xcoff_bfd_define_start_stop): Define.
	* coffcode.h (coff_bfd_define_start_stop): Define.
	* elfxx-target.h (bfd_elfNN_bfd_define_start_stop): Define.
	* i386msdos.c (msdos_bfd_define_start_stop): Define.
	* i386os9k.c (os9k_bfd_define_start_stop): Define.
	* ieee.c (ieee_bfd_define_start_stop): Define.
	* ihex.c (ihex_bfd_define_start_stop): Define.
	* libbfd-in.h (_bfd_nolink_bfd_define_start_stop): Define.
	* mach-o-target.c (bfd_mach_o_bfd_define_start_stop): Define.
	* mmo.c (mmo_bfd_define_start_stop): Define.
	* nlm-target.h (nlm_bfd_define_start_stop): Define.
	* oasys.c (oasys_bfd_define_start_stop): Define.
	* pef.c (bfd_pef_bfd_define_start_stop): Define.
	* plugin.c (bfd_plugin_bfd_define_start_stop): Define.
	* ppcboot.c (ppcboot_bfd_define_start_stop): Define.
	* som.c (som_bfd_define_start_stop): Define.
	* srec.c (srec_bfd_define_start_stop): Define.
	* tekhex.c (tekhex_bfd_define_start_stop): Define.
	* versados.c (versados_bfd_define_start_stop): Define.
	* vms-alpha.c (vms_bfd_define_start_stop): Define.
	(alpha_vms_bfd_define_start_stop): Define.
	* xsym.c (bfd_sym_bfd_define_start_stop): Define.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.
ld/
	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Don't set
	__start/__stop syms here.
	* ldlang.c (lang_set_startof): Delete.
	(start_stop_syms, start_stop_count, start_stop_alloc): New vars.
	(lang_define_start_stop, lang_init_start_stop, foreach_start_stop,
	undef_start_stop, lang_undef_start_stop, lang_init_startof_sizeof,
	set_start_stop, lang_finalize_start_stop): New functions.
	(lang_process): Call _start_stop functions.
	* testsuite/ld-elf/pr21562a.d: Use xfail rather than notarget.
	Correct typos and list of xfail targets.
	* testsuite/ld-elf/pr21562b.d: Likewise.
	* testsuite/ld-elf/pr21562c.d: Likewise.
	* testsuite/ld-elf/pr21562d.d: Likewise.
	* testsuite/ld-elf/pr21562e.d: Likewise.
	* testsuite/ld-elf/pr21562f.d: Likewise.
	* testsuite/ld-elf/pr21562g.d: Likewise.
	* testsuite/ld-elf/pr21562h.d: Likewise.
	* testsuite/ld-elf/pr21562i.d: Likewise.
	* testsuite/ld-elf/pr21562j.d: Likewise.
	* testsuite/ld-elf/pr21562k.d: Likewise.
	* testsuite/ld-elf/pr21562l.d: Likewise.
	* testsuite/ld-elf/pr21562m.d: Likewise.
	* testsuite/ld-elf/pr21562n.d: Likewise.
	* testsuite/ld-elf/sizeofa.d: Likewise.  Adjust to pass for generic ELF.
	* testsuite/ld-elf/sizeofb.d: Likewise.
	* testsuite/ld-elf/startofa.d: Likewise.
	* testsuite/ld-elf/startofb.d: Likewise.
 2017-06-16 23:38:28 +09:30
Andrew Burgess
7bdf4127c3 ld: Allow section groups to be resolved as part of a relocatable link 
This commit adds a new linker feature: the ability to resolve section
groups as part of a relocatable link.

Currently section groups are automatically resolved when performing a
final link, and are carried through when performing a relocatable link.
By carried through this means that one copy of each section group (from
all the copies that might be found in all the input files) is placed
into the output file.  Sections that are part of a section group will
not match input section specifiers within a linker script and are
forcibly kept as separate sections.

There is a slight resemblance between section groups and common
section.  Like section groups, common sections are carried through when
performing a relocatable link, and resolved (allocated actual space)
only at final link time.

However, with common sections there is an ability to force the linker to
allocate space for the common sections when performing a relocatable
link, there's currently no such ability for section groups.

This commit adds such a mechanism.  This new facility can be accessed in
two ways, first there's a command line switch --force-group-allocation,
second, there's a new linker script command FORCE_GROUP_ALLOCATION.  If
one of these is used when performing a relocatable link then the linker
will resolve the section groups as though it were performing a final
link, the section group will be deleted, and the members of the group
will be placed like normal input sections.  If there are multiple copies
of the group (from multiple input files) then only one copy of the group
members will be placed, the duplicate copies will be discarded.

Unlike common sections that have the --no-define-common command line
flag, and INHIBIT_COMMON_ALLOCATION linker script command there is no
way to prevent group resolution during a final link, this is because the
ELF gABI specifically prohibits the presence of SHT_GROUP sections in a
fully linked executable.  However, the code as written should make
adding such a feature trivial, setting the new resolve_section_groups
flag to false during a final link should work as you'd expect.

bfd/ChangeLog:

	* elf.c (_bfd_elf_make_section_from_shdr): Don't initially mark
	SEC_GROUP sections as SEC_EXCLUDE.
	(bfd_elf_set_group_contents): Replace use of abort with an assert.
	(assign_section_numbers): Use resolve_section_groups flag instead
	of relocatable link type.
	(_bfd_elf_init_private_section_data): Use resolve_section_groups
	flag instead of checking the final_link flag for part of the
	checks in here.  Fix white space as a result.
	* elflink.c (elf_link_input_bfd): Use resolve_section_groups flag
	instead of relocatable link type.
	(bfd_elf_final_link): Likewise.

include/ChangeLog:

	* bfdlink.h (struct bfd_link_info): Add new resolve_section_groups
	flag.

ld/ChangeLog:

	* ld.h (struct args_type): Add force_group_allocation field.
	* ldgram.y: Add support for FORCE_GROUP_ALLOCATION.
	* ldlex.h: Likewise.
	* ldlex.l: Likewise.
	* lexsup.c: Likewise.
	* ldlang.c (unique_section_p): Check resolve_section_groups flag
	not the relaxable link flag.
	(lang_add_section): Discard section groups when we're resolving
	groups.  Clear the SEC_LINK_ONCE flag if we're resolving section
	groups.
	* ldmain.c (main): Initialise resolve_section_groups flag in
	link_info based on command line flags.
	* testsuite/ld-elf/group11.d: New file.
	* testsuite/ld-elf/group12.d: New file.
	* testsuite/ld-elf/group12.ld: New file.
	* NEWS: Mention new features.
	* ld.texinfo (Options): Document --force-group-allocation.
	(Miscellaneous Commands): Document FORCE_GROUP_ALLOCATION.
 2017-06-06 09:53:38 +01:00
Alan Modra
bc4e12ded1 Rename non_ir_ref to non_ir_ref_regular 
Since the flag is now set only for regular object refs.

include/
	* bfdlink.h (struct bfd_link_hash_entry <non_ir_ref>): Rename to
	non_ir_ref_regular.
bfd/
	* elf-m10300.c: Rename occurrences of non_ir_ref.
	* elf32-arm.c: Likewise.
	* elf32-bfin.c: Likewise.
	* elf32-cr16.c: Likewise.
	* elf32-cris.c: Likewise.
	* elf32-d10v.c: Likewise.
	* elf32-dlx.c: Likewise.
	* elf32-fr30.c: Likewise.
	* elf32-frv.c: Likewise.
	* elf32-hppa.c: Likewise.
	* elf32-i370.c: Likewise.
	* elf32-i386.c: Likewise.
	* elf32-iq2000.c: Likewise.
	* elf32-lm32.c: Likewise.
	* elf32-m32c.c: Likewise.
	* elf32-m32r.c: Likewise.
	* elf32-m68hc1x.c: Likewise.
	* elf32-m68k.c: Likewise.
	* elf32-mcore.c: Likewise.
	* elf32-metag.c: Likewise.
	* elf32-microblaze.c: Likewise.
	* elf32-moxie.c: Likewise.
	* elf32-msp430.c: Likewise.
	* elf32-mt.c: Likewise.
	* elf32-nios2.c: Likewise.
	* elf32-or1k.c: Likewise.
	* elf32-ppc.c: Likewise.
	* elf32-rl78.c: Likewise.
	* elf32-s390.c: Likewise.
	* elf32-score.c: Likewise.
	* elf32-score7.c: Likewise.
	* elf32-sh.c: Likewise.
	* elf32-tic6x.c: Likewise.
	* elf32-tilepro.c: Likewise.
	* elf32-v850.c: Likewise.
	* elf32-vax.c: Likewise.
	* elf32-xstormy16.c: Likewise.
	* elf32-xtensa.c: Likewise.
	* elf64-alpha.c: Likewise.
	* elf64-hppa.c: Likewise.
	* elf64-ia64-vms.c: Likewise.
	* elf64-mmix.c: Likewise.
	* elf64-ppc.c: Likewise.
	* elf64-s390.c: Likewise.
	* elf64-sh64.c: Likewise.
	* elf64-x86-64.c: Likewise.
	* elflink.c: Likewise.
	* elfnn-aarch64.c: Likewise.
	* elfnn-ia64.c: Likewise.
	* elfnn-riscv.c: Likewise.
	* elfxx-mips.c: Likewise.
	* elfxx-sparc.c: Likewise.
	* elfxx-tilegx.c: Likewise.
	* linker.c: Likewise.
ld/
	* plugin.c: Rename occurrences of non_ir_ref.
 2017-05-16 10:35:02 +09:30
Alan Modra
4070765b1a non_ir_ref_dynamic 
dynamic_ref_after_ir_def is a little odd compared to other symbol
flags in that as the name suggests, it is set only for certain
references after a definition.  It turns out that setting a flag for
any non-ir reference from a dynamic object can be used to solve the
problem for which this flag was invented, which I think is a cleaner.
This patch does that, and sets non_ir_ref only for regular object
references.

include/
	* bfdlink.h (struct bfd_link_hash_entry): Update non_ir_ref
	comment.  Rename dynamic_ref_after_ir_def to non_ir_ref_dynamic.
ld/
	* plugin.c (is_visible_from_outside): Use non_ir_ref_dynamic.
	(plugin_notice): Set non_ir_ref for references from regular
	objects, non_ir_ref_dynamic for references from dynamic objects.
bfd/
	* elf64-ppc.c (add_symbol_adjust): Transfer non_ir_ref_dynamic.
	* elflink.c (elf_link_add_object_symbols): Update to use
	non_ir_ref_dynamic.
	(elf_link_input_bfd): Test non_ir_ref_dynamic in addition to
	non_ir_ref.
	* linker.c (_bfd_generic_link_add_one_symbol): Likewise.
 2017-05-16 10:35:02 +09:30
H.J. Lu
59fa66c538 Handle symbol defined in IR and referenced in DSO 
We need to make an IR symbol visible if it is defined in an IR object
and referenced in a dynamic object.  When --as-needed is used, since
linker removes the IR symbol reference of the dynamic object if the
dynamic object isn't needed in the first pass, the IR definition isn't
visible to the dynamic object even if the dynamic object becomes needed
in the second pass.  Add dynamic_ref_after_ir_def to bfd_link_hash_entry
to track IR symbol which is defined in an IR object and later referenced
in a dynamic object.  dynamic_ref_after_ir_def is preserved when restoring
the symbol table for unneeded dynamic object.

bfd/

	PR ld/21382
	* elflink.c (elf_link_add_object_symbols): Preserve
	dynamic_ref_after_ir_def when restoring the symbol table for
	unneeded dynamic object.

include/

	PR ld/21382
	* bfdlink.h (bfd_link_hash_entry): Add dynamic_ref_after_ir_def.

ld/

	PR ld/21382
	* plugin.c (is_visible_from_outside): Symbol may be visible
	from outside if dynamic_ref_after_ir_def is set.
	(plugin_notice): Set dynamic_ref_after_ir_def if the symbol is
	defined in an IR object and referenced in a dynamic object.
	* testsuite/ld-plugin/lto.exp: Run PR ld/21382 tests.
	* testsuite/ld-plugin/pr21382a.c: New file.
	* testsuite/ld-plugin/pr21382b.c: Likewise.
 2017-04-20 07:48:35 -07:00
Alan Modra
954b63d4c8 Implement -z dynamic-undefined-weak 
-z nodynamic-undefined-weak is only implemented for x86.  (The sparc
backend has some support code but doesn't enable the option by
including ld/emulparams/dynamic_undefined_weak.sh, and since the
support looks like it may be broken I haven't enabled it.)  This patch
adds the complementary -z dynamic-undefined-weak, extends both options
to affect building of shared libraries as well as executables, and
adds support for the option on powerpc.

include/
	* bfdlink.h (struct bfd_link_info <dynamic_undefined_weak>):
	Revise comment.
bfd/
	* elflink.c (_bfd_elf_adjust_dynamic_symbol): Hide undefweak
	or make dynamic for info->dynamic_undefined_weak 0 and 1.
	* elf32-ppc.c:Formatting.
	(ensure_undefweak_dynamic): Don't make dynamic when
	info->dynamic_undefined_weak is zero.
	(allocate_dynrelocs): Discard undefweak dyn_relocs for
	info->dynamic_undefined_weak.  Discard undef dyn_relocs when
	not default visibility.  Discard undef and undefweak
	dyn_relocs earlier.
	(ppc_elf_relocate_section): Adjust to suit.
	* elf64-ppc.c: Formatting.
	(ensure_undefweak_dynamic): Don't make dynamic when
	info->dynamic_undefined_weak is zero.
	(allocate_dynrelocs): Discard undefweak dyn_relocs for
	info->dynamic_undefined_weak.  Discard them earlier.
ld/
	* ld.texinfo (dynamic-undefined-weak): Document.
	(nodynamic-undefined-weak): Document that this option now can
	be used with shared libs.
	* emulparams/dynamic_undefined_weak.sh: Support -z
	dynamic-undefined-weak.
	* emulparams/elf32ppccommon.sh: Include dynamic_undefined_weak.sh.
	* testsuite/ld-undefined/weak-undef.exp (undef_weak_so),
	(undef_weak_exe): New.  Use them.  Add -z dynamic-undefined-weak
	and -z nodynamic-undefined-weak tests.
	* Makefile.am: Update powerpc dependencies.
	* Makefile.in: Regenerate.
 2017-04-19 20:39:52 +09:30
Alan Modra
2571583aed Update year range in copyright notice of all files. 2017-01-02 14:08:56 +10:30
fincs
221855059a Implement and document --gc-keep-exported 
include/
	* bfdlink.h (struct bfd_link_info): Add gc_keep_exported.
bfd/
	* elflink.c (bfd_elf_gc_mark_dynamic_ref_symbol): Add handling
	for info->gc_keep_exported.
	(bfd_elf_gc_sections): Likewise.
ld/
	* ld.texinfo: Document --gc-keep-exported.
	* ldlex.h (enum option_values): Add OPTION_GC_KEEP_EXPORTED.
	* lexsup.c (parse_args): Add handling for --gc-keep-exported.
 2016-12-16 13:49:03 +10:30
Thomas Preud'homme
7635954182 Add support for creating ELF import libraries 
2016-07-15  Thomas Preud'homme  <thomas.preudhomme@arm.com>

bfd/
	* elf-bfd.h (elf_backend_filter_implib_symbols): Declare backend hook.
	(_bfd_elf_filter_global_symbols): Declare.
	* elf.c (_bfd_elf_filter_global_symbols): New function.
	* elflink.c (elf_filter_global_symbols): Likewise.
	(elf_output_implib): Likewise.
	(bfd_elf_final_link): Call above function, failing if it does.
	* elfxx-target.h (elf_backend_filter_implib_symbols): Define macro and
	default it to NULL.
	(elf_backend_copy_indirect_symbol): Fix spacing.
	(elf_backend_hide_symbol): Likewise.
	(elfNN_bed): Initialize elf_backend_filter_implib_symbols backend hook.

include/
	* bfdlink.h (struct bfd_link_info): Declare new ldscript_def and
	out_implib_bfd fields.

2016-07-15  Thomas Preud'homme  <thomas.preudhomme@arm.com>
	    Nick Clifton  <nickc@redhat.com>

ld/
	* emultempl/elf32.em (gld${EMULATION_NAME}_after_open): Open import
	library file for writing and initialize implib_bfd field of link_info
	structure.
	* emultempl/pe.em (pe_implib_filename): Remove variable declaration.
	(OPTION_IMPLIB_FILENAME): Remove macro definition.
	(gld${EMULATION_NAME}_add_options): Remove --out-implib option.
	(gld_${EMULATION_NAME}_list_options): Likewise.
	(gld${EMULATION_NAME}_handle_option): Likewise.
	(gld_${EMULATION_NAME}_finish): Use command_line.out_implib_filename
	instead of pe_implib_filename.
	* emultempl/pep.em (pep_implib_filename): Remove variable declaration.
	(OPTION_IMPLIB_FILENAME): Remove enumerator.
	(gld${EMULATION_NAME}_add_options): Remove --out-implib option.
	(gld_${EMULATION_NAME}_list_options): Likewise.
	(gld${EMULATION_NAME}_handle_option): Likewise.
	(gld_${EMULATION_NAME}_finish): Use command_line.out_implib_filename
	instead of pep_implib_filename.
	* ld.h (args_type): Declare new out_implib_filename field.
	* ld.texinfo (--out-implib): Move documentation to arch-independent
	part and rephrase to apply to ELF targets.
	* ldexp.c (exp_fold_tree_1): Set ldscript_def field to 1 for symbols
	defined in linker scripts.
	* ldlex.h (enum option_values): Declare new OPTION_OUT_IMPLIB
	enumerator.
	* lexsup.c (ld_options): Add entry for new --out-implib switch.
	(parse_args): Handle OPTION_OUT_IMPLIB case.
	* testsuite/ld-elf/elf.exp (Generate empty import library): New test.
	(Generate import library): Likewise.
	* testsuite/ld-elf/implib.s: Likewise.
	* testsuite/ld-elf/implib.rd: New file.
	* testsuite/ld-elf/empty-implib.out: Likewise
 2016-07-15 17:50:48 +01:00
Alan Modra
1a72702bb3 Return void from linker callbacks 
The ldmain.c implementation of these linker callback functions always
return true, so any code handling a false return is dead.  What's
more, some of the bfd backends abort if ever a false return is seen,
and there seems to be some confusion in gdb's compile-object-load.c.
The return value was never meant to be "oh yes, a multiple_definition
error occurred", but rather "out of memory or other catastrophic
failure".

This patch removes the status return on the callbacks that always
return true.  I kept the return status for "notice" because that one
does happen to need to return "out of memory".

include/
	* bfdlink.h (struct bfd_link_callbacks): Update comments.
	Return void from multiple_definition, multiple_common,
	add_to_set, constructor, warning, undefined_symbol,
	reloc_overflow, reloc_dangerous and unattached_reloc.
bfd/
	* aoutx.h: Adjust linker callback calls throughout file,
	removing dead code.
	* bout.c: Likewise.
	* coff-alpha.c: Likewise.
	* coff-arm.c: Likewise.
	* coff-h8300.c: Likewise.
	* coff-h8500.c: Likewise.
	* coff-i960.c: Likewise.
	* coff-mcore.c: Likewise.
	* coff-mips.c: Likewise.
	* coff-ppc.c: Likewise.
	* coff-rs6000.c: Likewise.
	* coff-sh.c: Likewise.
	* coff-tic80.c: Likewise.
	* coff-w65.c: Likewise.
	* coff-z80.c: Likewise.
	* coff-z8k.c: Likewise.
	* coff64-rs6000.c: Likewise.
	* cofflink.c: Likewise.
	* ecoff.c: Likewise.
	* elf-bfd.h: Likewise.
	* elf-m10200.c: Likewise.
	* elf-m10300.c: Likewise.
	* elf32-arc.c: Likewise.
	* elf32-arm.c: Likewise.
	* elf32-avr.c: Likewise.
	* elf32-bfin.c: Likewise.
	* elf32-cr16.c: Likewise.
	* elf32-cr16c.c: Likewise.
	* elf32-cris.c: Likewise.
	* elf32-crx.c: Likewise.
	* elf32-d10v.c: Likewise.
	* elf32-epiphany.c: Likewise.
	* elf32-fr30.c: Likewise.
	* elf32-frv.c: Likewise.
	* elf32-ft32.c: Likewise.
	* elf32-h8300.c: Likewise.
	* elf32-hppa.c: Likewise.
	* elf32-i370.c: Likewise.
	* elf32-i386.c: Likewise.
	* elf32-i860.c: Likewise.
	* elf32-ip2k.c: Likewise.
	* elf32-iq2000.c: Likewise.
	* elf32-lm32.c: Likewise.
	* elf32-m32c.c: Likewise.
	* elf32-m32r.c: Likewise.
	* elf32-m68hc1x.c: Likewise.
	* elf32-m68k.c: Likewise.
	* elf32-mep.c: Likewise.
	* elf32-metag.c: Likewise.
	* elf32-microblaze.c: Likewise.
	* elf32-moxie.c: Likewise.
	* elf32-msp430.c: Likewise.
	* elf32-mt.c: Likewise.
	* elf32-nds32.c: Likewise.
	* elf32-nios2.c: Likewise.
	* elf32-or1k.c: Likewise.
	* elf32-ppc.c: Likewise.
	* elf32-s390.c: Likewise.
	* elf32-score.c: Likewise.
	* elf32-score7.c: Likewise.
	* elf32-sh.c: Likewise.
	* elf32-sh64.c: Likewise.
	* elf32-spu.c: Likewise.
	* elf32-tic6x.c: Likewise.
	* elf32-tilepro.c: Likewise.
	* elf32-v850.c: Likewise.
	* elf32-vax.c: Likewise.
	* elf32-visium.c: Likewise.
	* elf32-xstormy16.c: Likewise.
	* elf32-xtensa.c: Likewise.
	* elf64-alpha.c: Likewise.
	* elf64-hppa.c: Likewise.
	* elf64-ia64-vms.c: Likewise.
	* elf64-mmix.c: Likewise.
	* elf64-ppc.c: Likewise.
	* elf64-s390.c: Likewise.
	* elf64-sh64.c: Likewise.
	* elf64-x86-64.c: Likewise.
	* elflink.c: Likewise.
	* elfnn-aarch64.c: Likewise.
	* elfnn-ia64.c: Likewise.
	* elfxx-mips.c: Likewise.
	* elfxx-sparc.c: Likewise.
	* elfxx-tilegx.c: Likewise.
	* linker.c: Likewise.
	* pdp11.c: Likewise.
	* pe-mips.c: Likewise.
	* reloc.c: Likewise.
	* reloc16.c: Likewise.
	* simple.c: Likewise.
	* vms-alpha.c: Likewise.
	* xcofflink.c: Likewise.
	* elf32-rl78.c (get_symbol_value, get_romstart, get_ramstart): Delete
	status param.  Adjust calls to these and linker callbacks throughout.
	* elf32-rx.c: (get_symbol_value, get_gp, get_romstart,
	get_ramstart): Delete status param.  Adjust calls to these and
	linker callbacks throughout.
ld/
	* ldmain.c (multiple_definition, multiple_common, add_to_set,
	constructor_callback, warning_callback, undefined_symbol,
	reloc_overflow, reloc_dangerous, unattached_reloc): Return void.
	* emultempl/elf32.em: Adjust callback calls.
gdb/
	* compile/compile-object-load.c (link_callbacks_multiple_definition,
	link_callbacks_warning, link_callbacks_undefined_symbol,
	link_callbacks_undefined_symbol, link_callbacks_reloc_overflow,
	link_callbacks_reloc_dangerous,
	link_callbacks_unattached_reloc): Return void.
 2016-05-28 11:17:20 +09:30
Alan Modra
a6a4679fc0 Cache result of scan for __start_* and __stop_* sections 
include/
	* bfdlink.h (struct bfd_link_hash_entry): Add "section" field to
	undef.  Formatting.
bfd/
	* elflink.c (_bfd_elf_is_start_stop): New function.
	(_bfd_elf_gc_mark_rsec): Use it.
	* elf-bfd.h (_bfd_elf_is_start_stop): Declare.
 2016-04-27 17:05:26 +09:30
Nick Clifton
4f3b23b390 Add support for non-ELF targets to check their relocs. 
bfd	* aout-adobe.c: Use _bfd_generic_link_check_relocs.
	* aout-target.h: Likewise.
	* aout-tic30.c: Likewise.
	* binary.c: Likewise.
	* bout.c: Likewise.
	* coff-alpha.c: Likewise.
	* coff-rs6000.c: Likewise.
	* coff64-rs6000.c: Likewise.
	* coffcode.h: Likewise.
	* i386msdos.c: Likewise.
	* i386os9k.c: Likewise.
	* ieee.c: Likewise.
	* ihex.c: Likewise.
	* libbfd-in.h: Likewise.
	* libecoff.h: Likewise.
	* mach-o-target.c: Likewise.
	* mmo.c: Likewise.
	* nlm-target.h: Likewise.
	* oasys.c: Likewise.
	* pef.c: Likewise.
	* plugin.c: Likewise.
	* ppcboot.c: Likewise.
	* som.c: Likewise.
	* srec.c: Likewise.
	* tekhex.c: Likewise.
	* versados.c: Likewise.
	* vms-alpha.c: Likewise.
	* xsym.c: Likewise.
	* elfxx-target.h: Use _bfd_elf_link_check_relocs.
	* linker.c (bfd_link_check_relocs): New function.
	(_bfd_generic_link_check_relocs): New function.
	* targets.c (BFD_JUMP_TABLE_LINK): Add initialization of
	_bfd_link_check_relocs field.
	(struct bfd_target)L Add _bfd_link_check_relocs field.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.

ld	* ldlang.c (lang_check_relocs): Use bfd_link_check_relocs in
	prefernce to _bfd_elf_link_check_relocs.  Drop test for ELF
	targets.  Do not stop the checks when problems are encountered.

include	* bfdlink.h: Add prototype for bfd_link_check_relocs.
 2016-04-21 15:43:00 +01:00
H.J. Lu
d968975277 Check ELF relocs after opening all input files 
Delaying checking ELF relocations until opening all input files so
that symbol information is final when relocations are checked.  This
is only enabled for x86 targets.

bfd/

	* elf-bfd.h (_bfd_elf_link_check_relocs): New.
	* elflink.c (_bfd_elf_link_check_relocs): New function.
	(elf_link_add_object_symbols): Call _bfd_elf_link_check_relocs
	if check_relocs_after_open_input is FALSE.

include/

	* bfdlink.h (bfd_link_info): Add check_relocs_after_open_input.

ld/

	* emulparams/elf32_x86_64.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	New.
	* emulparams/elf_i386.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_be.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_chaos.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_ldso.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_i386_vxworks.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/elf_x86_64.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emulparams/i386nto.sh (CHECK_RELOCS_AFTER_OPEN_INPUT):
	Likewise.
	* emultempl/elf32.em (gld${EMULATION_NAME}_before_parse):
	Set check_relocs_after_open_input to TRUE if
	CHECK_RELOCS_AFTER_OPEN_INPUT is yes.
	(gld${EMULATION_NAME}_after_open): Call
	_bfd_elf_link_check_relocs on all inputs if
	check_relocs_after_open_input is TRUE.
 2016-04-20 05:26:51 -07:00
H.J. Lu
4c10bbaa09 Add -z noreloc-overflow option to x86-64 ld 
Add -z noreloc-overflow command-line option to the x86-64 ELF linker to
disable relocation overflow check.  This can be used to avoid relocation
overflow check if there will be no dynamic relocation overflow at
run-time.

bfd/

	PR ld/19807
	* elf64-x86-64.c (elf_x86_64_relocate_section): Check
	no_reloc_overflow_check to diable R_X86_64_32/R_X86_64_32S
	relocation overflow check.

include/

	PR ld/19807
	* bfdlink.h (bfd_link_info): Add no_reloc_overflow_check.

ld/

	PR ld/19807
	* Makefile.am (ELF_X86_DEPS): Add
	$(srcdir)/emulparams/reloc_overflow.sh.
	* Makefile.in: Regenerated.
	* NEWS: Mention -z noreloc-overflow.
	* ld.texinfo: Document -z noreloc-overflow.
	* emulparams/elf32_x86_64.sh: Source
	${srcdir}/emulparams/reloc_overflow.sh.
	* emulparams/elf_x86_64.sh: Likewise.
	* emulparams/reloc_overflow.sh: New file.
	* testsuite/ld-x86-64/pr19807-1.s: New file.
	* testsuite/ld-x86-64/pr19807-1a.d: Likewise.
	* testsuite/ld-x86-64/pr19807-1b.d: Likewise.
	* testsuite/ld-x86-64/pr19807-2.s: Likewise.
	* testsuite/ld-x86-64/pr19807-2a.d: Likewise.
	* testsuite/ld-x86-64/pr19807-2b.d: Likewise.
	* testsuite/ld-x86-64/pr19807-2c.d: Likewise.
	* testsuite/ld-x86-64/pr19807-2d.d: Likewise.
	* testsuite/ld-x86-64/pr19807-2e.d: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run PR ld/19807 tests.
 2016-03-15 11:07:54 -07:00