Also fixes m68hc1x printf arguments which would have bombed when
compiling on a 32-bit host with --enable-64-bit-bfd.
bfd/
PR 24955
* elf32-arm.c (set_cmse_veneer_addr_from_implib): Use bfd_malloc
rather than xmalloc.
* elf32-m68hc1x.c (reloc_warning): New function.
(elf32_m68hc11_relocate_section): Use it here. Cast bfd_vma values
corresponding to %lx in format strings.
* elf32-nds32.c (nds32_insertion_sort): Use a stack temporary.
gas/
* config/tc-nds32.c (nds32_set_section_relocs): Use relocs and n
parameters rather than equivalent sec->orelocation and
sec->reloc_count. Don't sort for n <= 1. Tidy.
This patch ensures qsort stability in line and function sorting done
in dwarf2.c. For the line sequences we make use of an existing field
that isn't used until later, as a monotonic counter for the qsort.
* dwarf2.c (struct lookup_funcinfo): Add idx field.
(compare_lookup_funcinfos): Perform final sort on idx.
(build_lookup_funcinfo_table): Set idx.
(compare_sequences): Perform final sort on num_lines.
(build_line_info_table): Set num_lines and line_info_lookup earlier.
(sort_line_sequences): Set num_lines for sort.
This particular sort almost certainly does not need to be stable for
the ELF linker to work correctly. However it is conceivable that an
unstable sort could affect linker output, and thus different output be
seen with differing qsort implementations. The argument goes like
this: Given more than one strong alias symbol of equal section, value,
and size, the aliases will compare equal by elf_sort_symbol and thus
which one is chosen as the "real" symbol to be made dynamic depends on
qsort. Why would anyone define two symbols at the same address?
Well, sometimes the fact that there are more than one strong alias
symbol is due to linker script symbols like __bss_start being made
dynamic. This will match the first symbol defined in .bss if it
doesn't have correct size, and forgetting to properly set size and
type of symbols isn't as rare as it should be.
This patch adds some more heuristics to elf_sort_symbol.
* elflink.c (elf_sort_symbol): Sort on type and name as well.
(elf_link_add_object_symbols): Style fix.
elf_sort_sections tried to ensure a stable qsort by using target_index
as the final comparison, but target_index hasn't been set by anything
at the time elf_sort_sections was run. This patch arrange to have
target_index set.
* elf.c (_bfd_elf_map_sections_to_segments): Init target_index
for sections about to be sorted.
(assign_file_positions_for_load_sections): Likewise.
(elf_sort_sections): Don't bother optimising both TOEND case.
* elflink.c (bfd_elf_final_link): Reset target_index.
The linker SHF_LINK_ORDER section sorting had a number of defects.
1) The ordering was by VMA, which won't work with overlays. LMA is
better.
2) Zero size sections can result in two sections at the same LMA/VMA.
When only one of the two sections at the same LMA is zero size,
that one must be first.
3) Warnings given by elf_get_linked_section_vma won't ever be emitted
since elf_object_p warns and excludes objects with zero sh_link on
a SHF_LINK_ORDER section.
4) Section offset was adjusted down rather than up by section
alignment, possibly creating overlapping sections.
5) Finding the linked section did so the hard way, rather than simply
using elf_linked_to_section.
* elflink.c (elf_get_linked_section_vma): Delete.
(compare_link_order): Use elf_linked_to_section and sort by lma,
size, and id.
(elf_fixup_link_order): Use size_t variables where appropriate.
Make use of elf_linked_to_section. Formatting. Properly align
sections.
qsort isn't guaranteed to be a stable sort, that is, elements
comparing equal according to the comparison function may be reordered
relative to their original ordering. Of course sometimes you may not
care, but even in those cases it is good to force some ordering
(ie. not have the comparison function return 0) so that linker output
is reproducible over different libc qsort implementations.
One way to make qsort stable (which the glibc manual incorrectly says
is the only way) is to augment the elements being sorted with a
monotonic counter of some kind, and use that counter as the final
arbiter of ordering in the comparison function.
Another way is to set up an array of pointers into the array of
elements, first pointer to first element, second pointer to second
element and so so, and sort the pointer array rather than the element
array. Final arbiter in the comparison function then is the pointer
difference. This works well with, for example, the symbol pointers
returned by _bfd_elf_canonicalize_symtab which point into a symbol
array.
This patch fixes a few places where sorting by symbol pointers is
appropriate, and adds comments where qsort stability is a non-issue.
* elf-strtab.c (strrevcmp): Comment.
* merge.c (strrevcmp): Likewise.
* elf64-ppc.c (compare_symbols): Correct final pointer comparison.
Comment on why comparing pointers ensures a stable sort.
* elflink.c (struct elf_symbol): Add void* to union.
(elf_sort_elf_symbol): Ensure a stable sort with pointer comparison.
(elf_sym_name_compare): Likewise.
(bfd_elf_match_symbols_in_sections): Style fix.
(elf_link_sort_cmp1): Comment.
stash_maybe_enable_info_hash_tables sets
stash->info_hash_status = STASH_INFO_HASH_ON;
regardless of the result of stash_maybe_update_info_hash_tables call. In
case it fails this results in repeated invocation of comp_unit_hash_info
for the same comp unit and assertion failure in this function.
Only set stash->info_hash_status = STASH_INFO_HASH_ON; when
stash_maybe_update_info_hash_tables is successful.
bfd/
2019-10-11 Max Filippov <jcmvbkbc@gmail.com>
* dwarf2.c (stash_maybe_enable_info_hash_tables): Only set
stash->info_hash_status = STASH_INFO_HASH_ON when
stash_maybe_update_info_hash_tables succeeds.
Evil testcase with two debug info sections, with sizes of 2aaaabac4ec1
and ffffd5555453b140 result in a total size of 1. Reading the first
section of course overflows the buffer and tramples on other memory.
PR 25070
* dwarf2.c (_bfd_dwarf2_slurp_debug_info): Catch overflow of
total_size calculation.
This functionality will generate a new GNU object attribute for the "data region"
has been added. This object attribute is used
mark whether the compiler has generated code assuming that data could be in the
upper or lower memory regions.
Code which assumes data is always in the lower memory region is incompatible
with code which uses the full memory range for data.
The patch also adds a new assembler directive ".mspabi_attribute" to handle the
existing MSPABI object attributes. GCC will now emit both .gnu_attribute and
.mspabi_attribute directives to indicate what options the source file was
compiled with.
The assembler will now check the values set in these directives against the
options that the it has been invoked with. If there is a discrepancy, the
assembler will exit with an error.
bfd * elf32-msp430.c (elf32_msp430_merge_mspabi_attributes): Rename to..
(elf32_msp430_merge_msp430_attributes): Add support for merging the GNU
object attribute for data region.
binutils* readelf.c (display_msp430_gnu_attribute): New.
(process_arch_specific): Use msp430 specific handler for GNU
attributes.
gas * config/tc-msp430.c (md_parse_option): Set lower_data_region_only to
FALSE if the data region is set to "upper", "either" or "none".
(msp430_object_attribute): New.
(md_pseudo_table): Handle .mspabi_attribute and .gnu_attribute.
(msp430_md_end): Replace hard-coded attribute values with enums.
Handle data region object attribute.
* doc/as.texi: Document MSP430 Data Region object attribute.
* doc/c-msp430.texi: Document the .mspabi_attribute directive.
* testsuite/gas/msp430/attr-430-small-bad.d: New test.
* testsuite/gas/msp430/attr-430-small-bad.l: New test.
* testsuite/gas/msp430/attr-430-small-good.d: New test.
* testsuite/gas/msp430/attr-430-small.s: New test.
* testsuite/gas/msp430/attr-430x-large-any-bad.d: New test.
* testsuite/gas/msp430/attr-430x-large-any-bad.l: New test.
* testsuite/gas/msp430/attr-430x-large-any-good.d: New test.
* testsuite/gas/msp430/attr-430x-large-any.s: New test.
* testsuite/gas/msp430/attr-430x-large-lower-bad.d: New test.
* testsuite/gas/msp430/attr-430x-large-lower-bad.l: New test.
* testsuite/gas/msp430/attr-430x-large-lower-good.d: New test.
* testsuite/gas/msp430/attr-430x-large-lower.s: New test.
* testsuite/gas/msp430/msp430.exp: Run new tests.
include * elf/msp430.h: Add enums for MSPABI and GNU object attribute tag names
and values.
ld * testsuite/ld-msp430-elf/attr-gnu-main.s: New test.
* testsuite/ld-msp430-elf/attr-gnu-obj.s: New test.
* testsuite/ld-msp430-elf/attr-gnu-region-lower-upper.d: New test.
* testsuite/ld-msp430-elf/attr-gnu-region-lower.d: New test.
* testsuite/ld-msp430-elf/attr-gnu-region-upper.d: New test.
* testsuite/ld-msp430-elf/msp430-elf.exp: Run new tests.
A bug crept into commit f749f26eea, which could cause linker
segfaults when creating PIEs. This patch fixes it.
* elf64-ppc.c (ppc64_elf_size_dynamic_sections): Do allocate
space for local got non-tls relocs when PIE.
This patch is a result of noticing messages like the following:
tmpdir/tls32.o: in function `_start':
(.text+0x1c): unresolvable R_PPC_REL24 relocation against symbol `__tls_get_addr_opt'
./ld-new: final link failed: symbol needs debug section which does not exist
The "needs debug section" comes from attempting to use debug info to
find source line information to print the first error message. That
error isn't of interest to the user, and any previous bfd_error value
which might be of interest is overwritten. So save and restore
bfd_error around the fancy error reporting code.
That still doesn't leave us with a clean bfd_error. Now we get
./ld-new: final link failed: nonrepresentable section on output
An unresolvable relocation surely doesn't mean there is some bfd
section that ld doesn't know how to output! Digging into that showed
a _bfd_elf_section_from_bfd_section failure attempting to find an elf
section correcsponding to ".interp". So don't go looking for elf
sections on linker created bfd sections.
And then fix the linker testsuite which expected the bogus message..
bfd/
* elflink.c (elf_fixup_link_order): Don't attempt to find
an elf_section for linker created bfd sections.
ld/
* ldmisc.c (vfinfo): Save and restore bfd_error around bfd
function calls that might set it.
* testsuite/ld-elf/indirect.exp: Don't expect "nonrepresentable
section" message.
ppc*_elf_tls_optimize decrements the PLT refcount for __tls_get_addr
when a GD or LD sequence can be optimized. Without tls marker relocs
this must be done when processing the argument setup relocations.
With marker relocs it's better done when processing the marker reloc.
But don't count them both ways.
Seen as "unresolvable R_PPC_REL24 relocation against symbol
`__tls_get_addr_opt'" (and other branch relocs).
* elf32-ppc.c (ppc_elf_tls_optimize): Don't process R_PPC_TLSLD
with non-local symbol. Don't double count __tls_get_addr calls
with marker relocs.
* elf64-ppc.c (ppc64_elf_tls_optimize): Likewise.
has_tls_get_addr_call is no longer named correctly as the flag is
only set on finding a __tls_get_addr call without tlsld/tlsgd marker
relocations.
* elf32-ppc.c (nomark_tls_get_addr): Rename from has_tls_get_addr_call
throughout.
* elf64-ppc.c (nomark_tls_get_addr): Likewise.
1) GOT entries generated for any of the GOT TLS relocations don't need
dynamic relocations for locally defined symbols in PIEs. In the case
of a tls_index doubleword, the dtpmod entry is known to be 1, and the
dtprel entry is also known at link time and relative. Similarly,
dtprel and tprel words are known at link time and relative. (GOT
entries for other than TLS symbols are not relative and thus need
dynamic relocations in PIEs.)
2) Local dynamic TLS code is really only meant for accesses local to
the current binary. There was a cheapskate test for this before using
the common tlsld_got slot, but the test wasn't exactly correct and
might confuse anyone looking at the code. The proper test,
SYMBOL_REFERENCES_LOCAL isn't so expensive that it should be avoided.
3) The same cheap test for local syms when optimising TLS sequences
should be SYMBOL_REFERENCES_LOCAL too.
bfd/
* elf64-ppc.c (ppc64_elf_check_relocs): Move initialisation of vars.
(ppc64_elf_tls_optimize): Correct is_local condition.
(allocate_got): Don't reserve dynamic relocations for any of the
tls got relocs in PIEs when the symbol is local.
(allocate_dynrelocs): Correct validity test for local sym using
tlsld_got slot.
(ppc64_elf_size_dynamic_sections): Don't reserve dynamic relocations
for any of the tls got relocs in PIEs.
(ppc64_elf_layout_multitoc): Likewise.
(ppc64_elf_relocate_section): Correct validity test for local sym
using tlsld_got slot. Don't emit dynamic relocations for any of
the tls got relocs in PIEs when the symbol is local.
* elf32-ppc.c (ppc_elf_tls_optimize): Correct is_local condition.
(got_relocs_needed): Delete.
(allocate_dynrelocs): Correct validity test for local sym using
tlsld_got slot. Don't reserve dynamic relocations for any of the
tls got relocs in PIEs when the symbol is local.
(ppc_elf_size_dynamic_sections): Don't reserve dynamic relocations
for any of the tls got relocs in PIEs.
(ppc_elf_relocate_section): Correct validity test for local sym
using tlsld_got slot. Don't emit dynamic relocations for any of
the tls got relocs in PIEs when the symbol is local.
ld/
* testsuite/ld-powerpc/tlsso.d: Adjust to suit tlsld_got usage change.
* testsuite/ld-powerpc/tlsso.g: Likewise.
* testsuite/ld-powerpc/tlsso.r: Likewise.
* testsuite/ld-powerpc/tlsso32.d: Likewise.
* testsuite/ld-powerpc/tlsso32.g: Likewise.
* testsuite/ld-powerpc/tlsso32.r: Likewise.
Dynamic relocs are only needed in an executable for TLS symbols if
those are defined in an external module and even then TLS access
can be relaxed to use IE model instead of GD.
Several bfd_link_pic checks are turned into bfd_link_dll checks
to fix TLS handling in PIE, for the same fix some other targets
used !bfd_link_executable checks, but that includes relocatable
objects so dll seems safer (in most cases either should work, since
dynamic relocations are not applied in relocatable objects).
On arm* fixes
FAIL: Build pr22263-1
bfd/
PR ld/22263
PR ld/25056
* elf32-arm.c (elf32_arm_tls_transition): Use bfd_link_dll instead of
bfd_link_pic for TLS checks.
(elf32_arm_final_link_relocate): Likewise.
(allocate_dynrelocs_for_symbol): Likewise.
On 64-bit host the 32-bit addend was loaded without sign extension into
an unsigned long.
bfd/ChangeLog:
PR ld/25062
* elf32-arm.c (elf32_arm_final_link_relocate): Sign extend data.
ld/ChangeLog:
PR ld/25062
* testsuite/ld-arm/arm-elf.exp: Update.
* testsuite/ld-arm/tls-gdesc-neg.d: New test.
* testsuite/ld-arm/tls-gdesc-neg.s: New test.
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.
The CTF linking process wants to deduplicate the CTF strtab against the
ELF strtab, for which it needs to know the number of strings in the
strtab and it needs to be able to extract them one by one.
The BFD strtab functions only support returning the
size-or-section-length of the strtab (with _bfd_elf_strtab_size)
and returning the offset (but not string!) and decrementing the refcount
at the same time.
So add new functions _bfd_elf_strtab_len (that just returns the length
in strings of the strtab, never the section size) and bfd_elf_strtab_str
(which returns the string at a given strtab index, and its offset,
without touching the refcount).
It is probably a mistake to use _bfd_elf_strtab_str in particular before
_bfd_elf_strtab_finalize is called, and will not produce useful output
if you do so.
v5: fix tabdamage.
bfd/
* elf-strtab.c (_bfd_elf_strtab_len): New.
(_bfd_elf_strtab_str): Likewise.
* bfd-elf.h: Declare them.
The code in ctf_bfdopen_ctfsect (which is the ultimate place where you
end up if you use ctf_open to open a CTF file and pull in the ELF string
and symbol tables) was written before it was possible to actually test
it, since the linker was not written. Now it is, it turns out that the
previous code was completely nonfunctional: it assumed that you could
load the symbol table via bfd_section_from_elf_index (...,elf_onesymtab())
and the string table via bfd_section_from_elf_index on the sh_link.
Unfortunately BFD loads neither of these sections in the conventional
fashion it uses for most others: the symbol table is immediately
converted into internal form (which is useless for our purposes, since
we also have to work in the absence of BFD for readelf, etc) and the
string table is loaded specially via bfd_elf_get_str_section which is
private to bfd/elf.c.
So make this function public, export it in elf-bfd.h, and use it from
libctf, which does something similar to what bfd_elf_sym_name and
bfd_elf_string_from_elf_section do. Similarly, load the symbol table
manually using bfd_elf_get_elf_syms and throw away the internal form
it generates for us (we never use it).
BFD allocates the strtab for us via bfd_alloc, so we can leave BFD to
deallocate it: we allocate the symbol table ourselves before calling
bfd_elf_get_elf_syms, so we still have to free it.
Also change the rules around what you are allowed to provide: It is
useful to provide a string section but no symbol table, because CTF
sections can legitimately have no function info or data object sections
while relying on the ELF strtab for some of their strings. So allow
that combination.
v4: adjust to upstream changes. ctf_bfdopen_ctfsect's first parameter
is potentially unused again (if BFD is not in use for this link
due to not supporting an ELF target).
v5: fix tabdamage.
bfd/
* elf-bfd.h (bfd_elf_get_str_section): Add.
* elf.c (bfd_elf_get_str_section): No longer static.
libctf/
* ctf-open-bfd.c: Add <assert.h>.
(ctf_bfdopen_ctfsect): Open string and symbol tables using
techniques borrowed from bfd_elf_sym_name.
(ctf_new_archive_internal): Improve comment.
* ctf-archive.c (ctf_arc_close): Do not free the ctfi_strsect.
* ctf-open.c (ctf_bufopen): Allow opening with a string section but
no symbol section, but not vice versa.
In check_relocs, bfd_link_pic true means ld is producing a shared
library or a position independent executable. !bfd_link_pic means a
fixed position (ie. static) executable since the relocatable linking
case is excluded. So it is appropriate to continue using bfd_link_pic
when testing whether non-pcrelative relocations should be dynamic, and
!bfd_link_pic for the special case of ifunc in static executables.
However, -Bsymbolic shouldn't affect PIEs (they are executables so
none of their symbols should be overridden) and PIEs can support copy
relocations, thus bfd_link_executable should be used in those cases
rather than bfd_link_pic.
I've also removed the test of ELIMINATE_COPY_RELOCS in check_relocs.
We can sort out what to do regarding copy relocs later, which allows
the code in check_relocs to be simplified.
* elf64-ppc.c (ppc64_elf_check_relocs): Use bfd_link_executable
in choosing between different actions for shared library and
non-shared library cases. Delete ELIMINATE_COPY_RELOCS test.
(dec_dynrel_count): Likewise. Account for ifunc special case.
(ppc64_elf_adjust_dynamic_symbol): Copy relocs are for executables,
not non-pic.
(allocate_dynrelocs): Comment fixes. Delete ELIMINATE_COPY_RELOCS
test.
Alan Modra
GDB Administrator
Max Filippov
Jozef Lawrynowicz
Szabolcs Nagy
Nick Alcock