When creating an archive, llvm-ar looks at the host to determine the
archive format to use, on Apple platforms this means it uses the
K_DARWIN format. K_DARWIN is _virtually_ equivalent to K_BSD, expect for
some very slight differences around padding, timestamps in deterministic
mode, and 64 bit formats. When updating an archive using llvm-ar, or
llvm-objcopy, Archive would try to determine the kind, but it was not
possible to get K_DARWIN in the initialization of the archive, because
they're virtually inciting usable from K_BSD, especially since the
slight differences only apply in very specific cases. This leads to
linker failures when the alignment workaround is not applied to an
archive copied with llvm-objcopy. This change teaches Archive to infer
the K_DARWIN type in the cases where it's possible and the first object
in the archive is a macho object. This avoids using the host triple to
determine this to not affect cross compiling.
Ideally we would eliminate the separate K_DARWIN type entirely since
it's not a truly separate archive type, but then we'd have to force the
macho workarounds on the BSD format generally. This might be acceptable
but then it would be unclear how to handle this case without forcing the
K_DARWIN64 format on all BSD users:
```
if (LastOffset >= Sym64Threshold) {
if (Kind == object::Archive::K_DARWIN)
Kind = object::Archive::K_DARWIN64;
else
Kind = object::Archive::K_GNU64;
}
```
The logic used to determine if the object is macho is derived from the
logic llvm-ar uses.
Previous context:
- 111cd669e9
- 23a76be5ad
Differential Revision: https://reviews.llvm.org/D124895
All of the other tests here either check that the copy fails, or that
the resulting binary is the same, it seems like this check was omitted
for the universal object case.
Differential Revision: https://reviews.llvm.org/D125478
SUMMARY
1. Enable supporting the write operation of big archive.
2. the first commit come from https://reviews.llvm.org/D104367
3. refactor the first commit and implement writing symbol table.
4. fixed the bugs and add more test cases in the second commit.
Reviewers: James Henderson
Differential Revision: https://reviews.llvm.org/D123949
D122746 missed the following tests, so this patch adds them.
This patch refactors D122949, which marked the following tests XFAIL, but it makes more sense to temporarily add `--format=gnu` option because these tests aren’t testing `llvm-ar` and AIX won’t lose their coverage.
Reviewed By: jhenderson, MaskRay, DiggerLin
Differential Revision: https://reviews.llvm.org/D123063
Big archive writer operation is not currently supported so mark these tests XFAIL for now.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D122949
This diff adds support for universal binaries to llvm-objcopy.
This is a recommit of 32c8435ef7 with the asan issue fixed.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D88400
Keith Smiley