If we fix https://github.com/llvm/llvm-project/issues/54184, we will end
up including libSystem in every %lld invocation, which would break
tapi-link.s as it assumes that libSystem isn't directly linked (instead
it goes through libReexportSystem).
Let's remove this unnecessary coupling, as well as use `split-file`
instead of having a separate file under `Inputs`.
Reviewed By: #lld-macho, oontvoo
Differential Revision: https://reviews.llvm.org/D120939
Per discussion on
https://reviews.llvm.org/D59709#inline-1148734, this seems like the
right course of action. `canBeOmittedFromSymbolTable()` subsumes and
generalizes the previous logic. In addition to handling `linkonce_odr`
`unnamed_addr` globals, we now also internalize `linkonce_odr` +
`local_unnamed_addr` constants.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D120173
Previously, we were using a syslibroot that pointed to macos while
linking against arch arm64_32, which didn't really make sense. It isn't
currently an issue, but will be if we add the `-lSystem` as part of
dealing with https://github.com/llvm/llvm-project/issues/54184.
If we fix https://github.com/llvm/llvm-project/issues/54184, the
`dyld_stub_binder` symbol will get included in every output dylib. This
would cause the addresses of the other symbols to shift, breaking the
test as it currently stands. Let's make the test more flexible.
Reviewed By: lgrey
Differential Revision: https://reviews.llvm.org/D120940
So far, we sort all discardable sections at the end, with only some
extra logic to make sure that the .reloc section is at the start
of that group of sections. But if there are other discardable
sections, other than .reloc, they must also be ordered before
.debug_* sections, to avoid leaving gaps if the executable is
stripped.
(Stripping executables doesn't remove all discardable sections,
only the ones named .debug_*).
Rust binaries seem to include a .rmeta section, which is marked
discardable. This fixes stripping such binaries if built with
dwarf debug info included.
This fixes issues observed in MSYS2 in
https://github.com/msys2/MINGW-packages/pull/10555.
Differential Revision: https://reviews.llvm.org/D120805
Show the name of of the archive in the error message as well as the name
of the object within it.
Differential Revision: https://reviews.llvm.org/D120689
This does tail merging (and deduplication) of the strings.
On a statically linked clang.exe, this shrinks the ~17 MB string
table by around 0.5 MB. This adds ~160 ms to the linking time
which originally was around 950 ms.
For cases where `-debug:symtab` or `-debug:dwarf` isn't set, the
string table is only used for long section names, where this
shouldn't make any difference at all.
Differential Revision: https://reviews.llvm.org/D120677
The previous code used an unbounded sprintf, which in theory can
overflow, writing either the null terminator or the last digits
into the next struct member.
In practice, in LLD, all long section names are written sequentially
first at the start of the string table, followed by all the long
symbol names. Due to this, even if the total string table would
end up large, the long section names have fairly short offsets,
which is why this hasn't been an issue in practice.
I don't think it's worth trying to write a test that produces an
executable with enough long section names to make the section names
themselves exceed 10^6 bytes, which is currently necessary to trigger
faults with the previous form.
Differential Revision: https://reviews.llvm.org/D120676
https://github.com/ClangBuiltLinux/linux/issues/1606
When GNU_PROPERTY_X86_FEATURE_1_IBT is enabled, ld.lld will create .plt output
section even if there is no PLT entry. Fix this by implementing
IBTPltSection::isNeeded instead of using the default code path (which always
returns true).
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D120600
ObjFile::parse combines symbol initialization and resolution. Many tasks
unrelated to symbol resolution can be postponed and parallelized. This patch
extracts local symbol initialization and parallelizes it.
Technically the new function initializeLocalSymbols can be merged into
ObjFile::postParse, but functions like getSrcMsg may access the
uninitialized (all nullptr) local part of InputFile::symbols.
Linking chrome: 1.02x as fast with glibc malloc, 1.04x as fast with mimalloc
Reviewed By: ikudrin
Differential Revision: https://reviews.llvm.org/D119909
This was based off @thakis' draft in {D103517}. I employed templates to ensure
the support for `-why_live` wouldn't slow down the regular non-why-live code
path.
No stat sig perf difference on my 3.2 GHz 16-Core Intel Xeon W:
base diff difference (95% CI)
sys_time 1.195 ± 0.015 1.199 ± 0.022 [ -0.4% .. +1.0%]
user_time 3.716 ± 0.022 3.701 ± 0.025 [ -0.7% .. -0.1%]
wall_time 4.606 ± 0.034 4.597 ± 0.046 [ -0.6% .. +0.2%]
samples 44 37
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D120377
* detect `def_tls.o undef_nontls.o` violation
* place error checking code (checking duplicate symbol) together
* allow `--defsym tls1=tls2 def_tls.o`
As a degraded error checking, `--defsym tls1=42` violation will not be detected.
Symbol.h depends on InputFiles.h. This change moves us toward dropping the
weird dependency.
The call sites will become slightly uglier (`cast<SharedFile>(s->file)`), but
the compromise is acceptable.
In GNU ld, the definition precedence is: regular symbol assignment > relocatable object definition > `PROVIDE` symbol assignment.
GNU ld's internal linker scripts define the non-reserved (by C and C++)
edata/end/etext with `PROVIDE` so the relocatable object definition takes
precedence. This makes sense because `int end;` is valid.
We currently redefine such symbols if they are COMMON, but not if they are
regular definitions, so `int end;` with -fcommon is essentially a UB in ld.lld.
Fix this (also improve consistency and match GNU ld) by using the
`isDefined` code path for `isCommon`. In GNU ld, reserved identifiers like
`__ehdr_start` do not use `PROVIDE`, while we treat them all as `PROVIDE`, this
seems fine.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D120389
This mirrors the code structure in `lld/ELF`. It also paves the way for
an upcoming diff where I templatize things.
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D120376
This is what the Clang standalone build does too. And setting this
seems to be required to get the standalone build to work on my Mac.
Reviewed By: #lld-macho, MaskRay, Ericson2314, smeenai
Differential Revision: https://reviews.llvm.org/D120269