As for now, llvm-objcopy renames only sections that are specified
explicitly in --rename-section, while GNU objcopy keeps names of
relocation sections in sync with their targets. For example:
> readelf -S test.o
...
[ 1] .foo PROGBITS
[ 2] .rela.foo RELA
> objcopy --rename-section .foo=.bar test.o gnu.o
> readelf -S gnu.o
...
[ 1] .bar PROGBITS
[ 2] .rela.bar RELA
> llvm-objcopy --rename-section .foo=.bar test.o llvm.o
> readelf -S llvm.o
...
[ 1] .bar PROGBITS
[ 2] .rela.foo RELA
This patch makes llvm-objcopy to match the behavior of GNU objcopy better.
Differential Revision: https://reviews.llvm.org/D110352
The re-use of this struct across iterations of the loop was causing
fields (specifically Name) to be incorrectly shared between multiple
sections.
Differential Revision: https://reviews.llvm.org/D108984
If the number of directories was 6 (equal to the DEBUG_DIRECTORY
index), patchDebugDirectory() was run even though the debug directory
is actually the 7th entry. Use <= in the comparison to fix that.
This fixes https://llvm.org/PR51243
Differential Revision: https://reviews.llvm.org/D106940
Reviewed by: jhenderson
This reapplies 71d7fed3bc which was
reverted by 3e2bd82f02. This change
includes the fix for breaking the sanitizer bots.
As seen in https://bugs.llvm.org/show_bug.cgi?id=48880 the current
implementation for parsing grouped short options can return unclear
error messages. This change fixes the example given in the ticket in
which a flag is incorrectly given an argument. Also when parsing a
group we now keep reading past the first incorrect option and output
errors for all incorrect options in the group.
Differential Revision: https://reviews.llvm.org/D108770
As seen in https://bugs.llvm.org/show_bug.cgi?id=48880 the current
implementation for parsing grouped short options can return unclear
error messages. This change fixes the example given in the ticket in
which a flag is incorrectly given an argument. Also when parsing a
group we now keep reading past the first incorrect option and output
errors for all incorrect options in the group.
Differential Revision: https://reviews.llvm.org/D108770
The --set-section-flags option was being ignored when adding a new
section. Take it into account if present.
Fixes https://llvm.org/PR51244
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D106942
As for now, llvm-objcopy sorts section headers according to the offsets
of the sections in the input file. That can corrupt section references
in the dynamic symbol table because it is a loadable section and as such
is not updated by the tool. Even though the section references are not
required for loading the binary correctly, they are still handy for a
user who analyzes the file.
While the patch removes global reordering of section headers, it layouts
the sections in the same way as before, i.e. according to their original
offsets. All that helps the output file to resemble the input better.
Note that the patch removes sorting SHT_GROUP sections to the start of
the list, which was introduced in D62620 in order to ensure that they
come before the group members, along with the corresponding test. The
original issue was caused by the sorting of section headers, so dropping
the sorting also resolves the issue.
Differential Revision: https://reviews.llvm.org/D107653
Fix an edge case missed by https://reviews.llvm.org/D78921. For e.g.,
the Repro debug entry (generated with the /Brepro linker flag) does not
have a debug-directory payload. Do not attempt to patch Debug entries
without a payload.
Differential Revision: https://reviews.llvm.org/D107324
The LC_SUB_FRAMEWORK, LC_SUB_UMBRELLA, LC_SUB_CLIENT, and LC_SUB_LIBRARY
are used to indicate related libraries, binaries or framework names.
Their only payload is the string with the name of the object. Adding
those commands to the list of ignored/skipped load commands will avoid
an error that stop the process of copying/stripping and will copy their
contents verbatim.
Additionally, in order to have a test for this case, `yaml2obj` now
allows those four commands to contain a `Content`.
Differential Revision: https://reviews.llvm.org/D106412
See [GRP_COMDAT group with STB_LOCAL signature](https://groups.google.com/g/generic-abi/c/2X6mR-s2zoc)
objcopy PR: https://sourceware.org/bugzilla/show_bug.cgi?id=27931
GRP_COMDAT deduplication is purely based on the signature symbol name in
ld.lld/GNU ld/gold. The local/global status is not part of the equation.
If the signature symbol is localized by --localize-hidden or
--keep-global-symbol, the intention is likely to make the group fully
localized. Drop GRP_COMDAT to suppress deduplication.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D106782
Use double pound at the start of the line to differentiate comments from
statements for Lit or FileCheck.
I will also use this small commit to check my commit access.
Differential Revision: https://reviews.llvm.org/D106103
Summary:
Add support for the basic section stripping (and keeping) flags for wasm:
strip with no flags, --strip-all, --strip-debug,
--only-section, --keep-section, and --only-keep-debug.
Factor section removal into a function and use a predicate chain like
the ELF implementation.
Reviewers: jhenderson, sbc100
Differential Revision: https://reviews.llvm.org/D73820
GNU and Apple `strip` implementations seems to support grouped options.
Enable the support for grouped options introduced in
https://reviews.llvm.org/D83639 for `llvm-strip` invocations.
Includes test that checks that both the grouped and non grouped
invocations produces the same result.
Reviewed By: alexander-shaposhnikov, MaskRay
Differential Revision: https://reviews.llvm.org/D105249
The load command is currently specific to arm64 and holds information
for instruction rewriting, e.g. converting a GOT load to an ADR to
compute a local address.
(On ELF the information is usually conveyed by relocations, e.g.
R_X86_64_REX_GOTPCRELX, R_PPC64_TOC16_HA)
Reviewed By: alexander-shaposhnikov
Differential Revision: https://reviews.llvm.org/D104968
An ARM64_RELOC_ADDEND relocation reuses the symbol field for the addend value.
We should pass through such relocations.
Reviewed By: alexander-shaposhnikov
Differential Revision: https://reviews.llvm.org/D104967
There is no need to differentiate whether `UseSegments` is true or
false. Unifying the cases makes the behavior closer to BinaryWriter.
This improves compatibility with objcopy because SHF_ALLOC sections not in
a PT_LOAD will not be skipped. Such cases are usually erroneous input, though.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D104186
IHexWriter was evaluating a section's physical address when deciding if
that section should be written to an output. This approach does not
account for a zero-sized section that has the same physical address as a
sized section. The behavior varies from GNU objcopy, and may result in a
HEX file that does not include all program sections.
The IHexWriter now excludes zero-sized sections when deciding what
should be written to the output. This affects the contents of the
writer's `Sections` collection; we will not try to insert multiple
sections that could have the same physical address. The behavior seems
consistent with GNU objcopy, which always excludes empty sections,
no matter the address.
The new test case evaluates the IHexWriter behavior when provided a
variety of empty sections that overlap or append a filled section. See
the input file's comments for more information. Given that test input,
and the change to the IHexWriter, GNU objcopy and llvm-objcopy produce
the same output.
Reviewed By: jhenderson, MaskRay, evgeny777
Differential Revision: https://reviews.llvm.org/D101332
This will allow to use llvm-strip with file names that begin with dashes.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D102825
This will allow to use llvm-objcopy with file names that begin with dashes.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D102665
PR50160: we currently ignore non-PT_PHDR segments with no sections, not
accounting for its p_offset and p_filesz: this can cause an out-of-bounds write
in `writeSegmentData` if the p_offset+p_filesz is larger than the total file
size.
This can be fixed by setting p_offset=p_filesz=0. The logic nicely unifies with
the logic added in D90897.
Reviewed By: jhenderson, rupprecht
Differential Revision: https://reviews.llvm.org/D101560
Fix PR45416: the diagnostic when '=' is missing is misleading.
`FileOutputBuffer::create` returns successfully when the filename is empty
(the temporary file is `.tmp%%%%%%%`), but `FileOutputBuffer::commit` will error when
renaming `.tmp%%%%%%%` to the empty name).
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D101697
The right symbol flag mask is ~0x7, not ~0xf.
Also emit string names for the other flags (we were missing some).
Reviewed By: #lld-macho, gkm
Differential Revision: https://reviews.llvm.org/D101548
Add support for LC_THREAD/LC_UNIXTHREAD
(these load commands can be copied over without any modifications).
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D101384
Add support for LC_THREAD/LC_UNIXTHREAD
(these load commands can be copied over without any modifications).
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D101384
This diff introduces --keep-undefined in llvm-objcopy/llvm-strip for Mach-O
which makes the tools preserve undefined symbols.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D97040
The code was using the standard isalnum function which doesn't handle
values outside the non-ascii range. Switching to using llvm::isAlnum
instead ensures we don't provoke undefined behaviour, which can in some
cases result in crashes.
Reviewed by: MaskRay
Differential Revision: https://reviews.llvm.org/D97663
The test was showing that when --strip-unneeded is specified for an
executable, all the symbols are stripped. However, the set of symbols
used in the test would be stripped by --strip-unneeded for an ET_REL
object too. Fix this by adding additional symbols that aren't normally
stripped by --strip-unneeded.
Reviewed by: MaskRay
Differential Revision: https://reviews.llvm.org/D97664
This patch adds a number of new test cases that cover various
llvm-objcopy and llvm-strip features that had missing test coverage of
various descriptions:
* --add-section - checked the shdr properties, not just the content.
* Dedicated test case for --add-symbol when there are many sections.
* Show that --change-start accepts negative values without overflow.
This was previously present but got lost between review versions.
* --dump-section - show that multiple sections can be dumped
simultaneously to different files, and that an error is reported when
a section cannot be found.
* --globalize-symbol(s) - show that symbols that are not mentioned are
not globalized, if they would otherwise be, and that missing symbols
from the list do not cause problems.
* --keep-global-symbol - show that the --regex option can be used in
conjunction with this option.
* --keep-symbol - show that the --regex option can be used in
conjunction with this option.
* --localize-symbol(s) - show that symbols that are not mentioned are
not localized, if they would otherwise be, and that missing symbols
from the list do not cause problems.
* --prefix-alloc-sections - show the behaviour of an empty string
argument and multiple arguments.
* --prefix-symbols - show the behaviour of an empty string argument and
multiple arguments. Also show the option applies to undefined symbols.
* --redefine-symbol - show that symbols with no name can be renamed,
that it is not an error if a symbol is not specified, and that the
option doesn't chain (i.e. --redefine-sym a=b --redefine-sym b=c does
not redefine a as c).
* --rename-section - show that all section flags are preserved if none
are specified. Also show that the option does not chain.
* --set-section-alignment - show that only specified sections have
their alignments changed.
* --set-section-flags - show which section flags are preserved when this
option is used. Also show that unspecified sections are not affected.
* --preserve-dates - show that -p is an alias of --preserve-dates.
* --strip-symbol - show that --regex works with this option for
llvm-objcopy as well as llvm-strip.
* --strip-unneeded-symbol(s) - show more clearly that needed symbols are
not stripped even if requested by this option.
* --allow-broken-links - show the sh_link of a symbol table is set to 0
when its string table has been removed when this option is specified.
* --weaken-symbol(s) - show that symbols that are not mentioned are not
weakened, if they would otherwise be, and that missing symbols from
the list do not cause problems.
* --wildcard - show the wildcard behaviour for several options that were
previously unchecked.
Reviewed by: alexshap
Differential Revision: https://reviews.llvm.org/D97666
The check for whether an extended symbol index table was required
dropped the first SHN_LORESERVE sections from the sections array before
checking whether the remaining sections had symbols. Unfortunately, the
null section header is not present in this list, so the check was
skipping the first section that might be important. If that section
contained a symbol, and no subsequent ones did, the .symtab_shndx
section would not be emitted, leading to a corrupt object.
Also consolidate and expand test coverage in the area to cover this bug
and other aspects of the SYMTAB_SHNDX section.
Reviewed by: alexshap, MaskRay
Differential Revision: https://reviews.llvm.org/D97661
Additionally do some test tidy-ups and improve coverage of symbol
section indexes where the logical section index >= SHN_LORESERVE.
The symbol and section names in the many-section input object were
mostly shared. This patch changes them to be distinct, enabling
different operations such as --add-symbol, to be more targeted, when
using the object. It also makes the test less confusing and removes some
oddness in the symbol table order, presumably caused by the duplicate
names.
The input object was built from assembly that was of the form:
.section s1
sym1:
.section s2
sym2:
...
with a total of 65536 such occurrences. llvm-objcopy was then used to
remove the empty .text section automatically generated by MC, and
incidentally to move .strtab to the end of the object. This ensured that
the section/symbol indexes matched their name (i.e. section index 1 was
s1, section index 2 was s2 etc, and sym1 was in s1, sym2 in s2 etc).
Reviewed by: MaskRay
Differential Revision: https://reviews.llvm.org/D97660
This makes the behavior similar to cp
```
chmod u+s,g+s,o+x a
sudo llvm-strip a -o b
// With this patch, b drops set-user-ID and set-group-ID bits.
// sudo cp a b => b does not have set-user-ID or set-group-ID bits.
```
This also changes the behavior for the following case:
```
chmod u+s,g+s,o+x a
llvm-strip a
// a preserves set-user-ID and set-group-ID bits.
// This matches binutils<2.36 and probably >=2.37. 2.36 and 2.36.1 have some compatibility issues.
```
Differential Revision: https://reviews.llvm.org/D97253
The few options are niche. They solved a problem which was traditionally solved
with more shell commands (`llvm-readelf -n` fetches the Build ID. Then
`ln` is used to hard link the file to a directory derived from the Build ID.)
Due to limitation, they are no longer used by Fuchsia and they don't appear to
be used elsewhere (checked with Google Search and Debian Code Search). So delete
them without a transition period.
Announcement: https://lists.llvm.org/pipermail/llvm-dev/2021-February/148446.html
Differential Revision: https://reviews.llvm.org/D96310
This is consistent with BFD objcopy.
Previously llvm objcopy would allocate space for SHT_NOBITS sections
often resulting in enormous binary files.
New test case (binary-paddr.test %t6).
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D95569
On z/OS, the following error message is not matched correctly in lit tests.
```
EDC5129I No such file or directory.
```
This patch uses a lit config substitution to check for platform specific error messages.
Reviewed By: muiez, jhenderson
Differential Revision: https://reviews.llvm.org/D95246
We already set the `sh_entsize` field in a single place
for all non-implicit sections.
This patch reorders the logic slightly and with it
we finally have the only one place where the `sh_entsize` is set.
obj2yaml will not dump the `EntSize` key for `SHT_DYNSYM/SHT_SYMTAB` sections anymore,
when the value of `sh_entsize` is equal to `sizeof(Elf_Sym)`
Note that this also seems revealed an issue in llvm-objcopy:
Previously yaml2obj set the `sh_entsize` for the `.symtab` section to 0x18,
now we it sets it for `SHT_SYMTAB` sections, i.e. by type.
But the `llvm-objcopy/ELF/only-keep-debug.test` has a `.symtab` section of type `SHT_STRTAB`,
and now yaml2obj sets the `sh_entsize` to 0 for it.
I had to update the corresponding check lines for `ES`, but the behavior of
`llvm-objcopy` should be fixed instead I think.
I've added a TODO and a comment.
Differential revision: https://reviews.llvm.org/D95364
On z/OS, the following error message is not matched correctly in lit tests. This patch updates the CHECK expression to match successfully.
```
EDC5129I No such file or directory.
```
Reviewed By: muiez
Differential Revision: https://reviews.llvm.org/D94239
Igor Kudrin