The flag doesn't (and shouldn't) have an effect in that case.
ld64 doesn't warn on this, but it seems like a good thing to do.
If it causes problems in practice for some reason, we can revert it.
Also add a dedicated test for install_name.
Differential Revision: https://reviews.llvm.org/D98259
lld doesn't read MH_DEAD_STRIPPABLE_DYLIB to strip dead dylibs yet,
but now it can produce dylibs with it set.
While here, also switch an existing test that looks only at the main Mach-O
header from --all-headers to --private-header.
Differential Revision: https://reviews.llvm.org/D98262
A `local:` version node in a version script can change the effective symbol binding
to STB_LOCAL. The linker needs to communicate the fact to enable WPD
(otherwise LTO does not know that the `!vcall_visibility` metadata has
effectively changed from VCallVisibilityPublic to VCallVisibilityLinkageUnit).
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D98220
Top-level `using llvm::opt` has been present in `lld/MachO/Driver*.cpp` for some time, so remove lingering `opt::` prefixes.
Differential Revision: https://reviews.llvm.org/D98314
lld policy discourages `auto`. Replace it with a type name whenever reasonable. Retain `auto` to avoid ...
* redundancy, as for decls such as `auto *t = mumble_cast<TYPE *>` or similar that specifies the result type on the RHS
* verbosity, as for iterators
* gratuitous suffering, as for lambdas
Along the way, add `const` when appropriate.
Note: a future diff will ...
* add more `const` qualifiers
* remove `opt::` when we are already `using llvm::opt`
Differential Revision: https://reviews.llvm.org/D98313
Implement command-line options to alter a dylib's exported-symbols list:
* `-exported_symbol*` options override the default export list. The export list is compiled according to the command-line option(s) only.
* `-unexported_symbol*` options hide otherwise public symbols.
* `-*exported_symbol PATTERN` options specify a single literal or glob pattern.
* `-*exported_symbols_list FILE` options specify a file containing a series of lines containing symbol literals or glob patterns. Whitespace and `#`-prefix comments are stripped.
Note: This is a simple implementation of the primary use case. ld64 has much more complexity surrounding interactions with other options, many of which are obscure and undocumented. We will start simple and complexity as necessary.
Differential Revision: https://reviews.llvm.org/D98223
Add first bits for emitting LC_FUNCTION_STARTS.
This is a recommit of f344dfeb with the adjusted test
which should address build bots breakages.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D97260
This `R_WASM_MEMORY_ADDR_SELFREL_I32` relocation represents an offset
between its relocating address and the symbol address. It's very similar
to `R_X86_64_PC32` but restricted to be used for only data segments.
```
S + A - P
```
A: Represents the addend used to compute the value of the relocatable
field.
P: Represents the place of the storage unit being relocated.
S: Represents the value of the symbol whose index resides in the
relocation entry.
Proposal: https://github.com/WebAssembly/tool-conventions/issues/162
Differential Revision: https://reviews.llvm.org/D96659
This changes the target data layout to make stack align to 16 bytes
on Power10. Before this change, stack was being aligned to 32 bytes.
Reviewed By: #powerpc, nemanjai
Differential Revision: https://reviews.llvm.org/D96265
These are mostly things that ld64 has itself marked obsolete.
In the case of `-sectorder`, it's suggested in ld64's manpage that it
could be deprecated, so let's skip implementing it for now.
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D98066
clang appears to emit symbols in `__debug_aranges`, at least
for arm64... in the examples I've seen, it doesn't seem like those
symbols are referenced outside of `__DWARF`, so I think they're safe to
ignore. But hopefully @clayborg can confirm.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D98073
We'll need to properly handle object files with multiple source inputs
eventually, but remove the assert for now so we can successfully emit binaries
for testing.
Reviewed By: #lld-macho, smeenai
Differential Revision: https://reviews.llvm.org/D98067
With this, llvm-tblgen no longer tries and fails to allocate 7953 petabyte
when it runs during the build. Instead, `check-llvm` with lld/mac as host
linker now completes without any failures on an m1 mac.
This vector op handling code matches what happens in:
- ld64's OutputFile::applyFixUps() in OutputFile.cpp for kindStoreARM64PageOff12
- lld.ld64.darwinold's offset12KindFromInstruction() in
lld/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp for offset12scale16
- RuntimeDyld's decodeAddend() in
llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldMachOAArch64.h for
ARM64_RELOC_PAGEOFF12
Fixes PR49444.
Differential Revision: https://reviews.llvm.org/D98053
Previously, lld/mac only ad-hoc codesigned executables on arm64.
Matches ld64 behavior. Part of PR49443. Fixes 14 of 17 failures when running
check-llvm with lld as host linker on an M1 MBP.
Differential Revision: https://reviews.llvm.org/D97994
This patch fixes LLD to allow element sections for tables whose number
is nonzero. We also add a test for linking multiple tables, showing
that nonzero table numbers for the indirect function table,
user-declared imported tables, and local user table definitions work.
Differential Revision: https://reviews.llvm.org/D92321
Since multiple dylibs can be defined in one TBD, this is
necessary to avoid confusion.
Reviewed By: #lld-macho, oontvoo
Differential Revision: https://reviews.llvm.org/D97905
Previously, we were loading re-exports without checking whether
they were compatible with our target. Prior to {D97209}, it meant that
we were defining dylib symbols that were invalid -- usually a silent
failure unless our binary actually used them. D97209 exposed this as an
explicit error.
Along the way, I've extended our TAPI compatibility check to cover the
platform as well, instead of just checking the arch. To this end, I've
replaced MachO::Architecture with MachO::Target in our Config struct.
Reviewed By: #lld-macho, oontvoo
Differential Revision: https://reviews.llvm.org/D97867
The reexport-nested-libs test added in D97438 was a bit wonky.
First, it was linking against libReexportSystem.tbd which targets the
iOS simulator, and which in turn attempted to re-export the iOS
simulator's libSystem. However, due to the way `-syslibroot` works, it
was actually re-exporting the macOS libSystem.
As a result, the test was not actually able to resolve the symbols in
the desired libSystem. I'm guessing that @oontvoo was confused by this
and therefore included those symbols in libReexportSystem.tbd itself.
But this means that the test wasn't actually testing the resolution of
re-exported symbols (though it did at least verify that the re-exported
libraries could be located).
After some consideration, I figured that stub-link.s could be extended
to cover what reexport-nested-libs.s was attempting to do. The test
targets macOS, so we only have one `-syslibroot` and no chance of
confusion.
Reviewed By: #lld-macho, oontvoo
Differential Revision: https://reviews.llvm.org/D97866
Suppose we are linking against libFoo, which re-exports the
implicitly-bound libSystem, which in turn re-exports some
non-explicitly-bound library like `/usr/lib/system/libsystem_c.dylib`.
Then any bindings we have to a symbol in libsystem_c should use
libSystem (and not libFoo) as the umbrella library.
Reviewed By: #lld-macho, smeenai
Differential Revision: https://reviews.llvm.org/D97865
Implemented the option to omit Power10 instructions from save stubs via the
option --no-power10-stubs or --power10-stubs=no on lld. --power10-stubs= will
override the other option. --power10-stubs=auto also exists to use the default
behaviour (ie allow Power10 instructions in stubs).
Differential Revision: https://reviews.llvm.org/D94627
llvm-objdump only uses one MCInstrAnalysis object, so if ARM and Thumb
code is mixed in one object, or if an object is disassembled without
explicitly setting the triple to match the ISA used, then branch and
call targets will be printed incorrectly.
This could be fixed by creating two MCInstrAnalysis objects in
llvm-objdump, like we currently do for SubtargetInfo. However, I don't
think there's any reason we need two separate sub-classes of
MCInstrAnalysis, so instead these can be merged into one, and the ISA
determined by checking the opcode of the instruction.
Differential revision: https://reviews.llvm.org/D97766
We previously defaulted to x86_64 and an unknown platform, which was fine when
we only supported one arch and did no platform checks, but that will no longer
be true going ahead. Therefore, we should require those flags to be specified
whenever the linker is invoked.
Note that LLD-ELF and ld64 both infer the arch from their input object files,
but the usefulness of that is questionable since clang will always specify these
flags, and most of the time `lld` will be invoked via clang.
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D97799
The option-iterating loop should be reserved for options whose command-line
order is important. I think LLD-ELF follows a similar design.
Reviewed By: #lld-macho, smeenai
Differential Revision: https://reviews.llvm.org/D97797
This reverts diff D97610 (commit 0223ab035c) and adds a one-line fix to verify that a `MemoryBufferRef` has sufficient length before reading a 4-byte magic number.
Differential Revision: https://reviews.llvm.org/D97757
Currently, it was delibrately impleneted to not handle this case, but as it has turnt out, we need this feature.
The concrete use case is
`System/Library/Frameworks/Cocoa.framework/Versions/A/Cocoa` reexports
/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit , which then rexports
/System/Library/PrivateFrameworks/UIFoundation.framework/Versions/A/UIFoundation
The current implemention uses a global currentTopLevelTapi, which is not reset until it finishes loading the whole tree.
This is a problem because if the top-level is set to Cocoa, then when we get to UIFoundation, it will try to find UIFoundation in the current top level, which is Cocoa and will not find it.
The right thing should be:
- When loading a library from a TBD file, re-exports need to be looked up in the auxiliary documents within the same TBD.
- When loading from an actual dylib, no additional TBD documents need to be examined.
- In no case does a re-export mentioned in one TBD file need to be looked up in a document in an auxiliary document from a different TBD file
Differential Revision: https://reviews.llvm.org/D97438
In AArch32 ARM, the PC reads two instructions ahead of the currently
executiing instruction. This evaluates to 8 in ARM state and 4 in
Thumb state. Branch instructions on AArch32 compensate for this by
subtracting the PC bias from the addend. For a branch to symbol this
will result in an addend of -8 in ARM state and -4 in Thumb state.
The existing ARM Target::inBranchRange function accounted for this
implict addend within the function meaning that if the addend were
to be taken into account by the caller then it would be double
counted. This complicates the interface for all Targets as callers
wanting to account for addends had to account for the ARM PC-bias.
In certain situations such as:
https://github.com/ClangBuiltLinux/linux/issues/1305
the PC-bias compensation code didn't match up. In particular
normalizeExistingThunk() didn't put the PC-bias back in as Arm
thunks did not store the addend.
The simplest fix for the problem is to add the PC bias in
normalizeExistingThunk when restoring the addend. However I think
it is worth refactoring the Arm inBranchRange implementation so
that fewer calls to getPCBias are needed for other Targets. I
wasn't able to remove getPCBias completely but hopefully the
Relocations.cpp code is simpler now.
In principle a test could be written to replicate the linux kernel
build failure but I wasn't able to reproduce with a small example
that I could build up from scratch.
Fixes https://github.com/ClangBuiltLinux/linux/issues/1305
Differential Revision: https://reviews.llvm.org/D97550
A couple of small changes to match the ELF linker in preparation
for adding support string mergings.
Differential Revision: https://reviews.llvm.org/D97654
This adds support for `-undefined dynamic_lookup`, and for
`-undefined warning` and `-undefined suppress` with `-flat_namespace`.
We just replace undefined symbols with a DynamicLookup when we hit them.
With this, `check-llvm` passes when using ld64.lld.darwinnew as host linker.
Differential Revision: https://reviews.llvm.org/D97642
-flat_namespace makes lld emit binaries that use name lookup that's more in
line with other POSIX systems: Instead of looking up symbols as (dylib,name)
pairs by dyld, they're instead looked up just by name.
-flat_namespace has three effects:
1. MH_TWOLEVEL and MH_NNOUNDEFS are no longer set in the Mach-O header
2. All symbols use BIND_SPECIAL_DYLIB_FLAT_LOOKUP as ordinal
3. When a dylib is added to the link, its dependent dylibs are also added,
so that lld can verify that no undefined symbols remain at the end of
a link with -flat_namespace. These transitive dylibs are added for symbol
resolution, but they are not emitted in LC_LOAD_COMMANDs.
-undefined with -flat_namespace still isn't implemented. Before this change,
it was impossible to hit that combination because -flat_namespace caused a
diagnostic. Now that it no longer does, emit a dedicated temporary diagnostic
when both flags are used.
Differential Revision: https://reviews.llvm.org/D97641
For -flat_namespace, lld needs to load dylibs in LC_LOAD_DYLIB.
The current setup meant that libSystem.dylib would cause a LC_LOAD_DYLIB
with libSystem.B.dylib, but that didn't exist in our libsysroot for
tests. So just drop the .B.
See https://reviews.llvm.org/D97641#2595237 and
https://reviews.llvm.org/D97641#2595270
Matches the ELF and COFF ports, which use ld.lld and lld-link, respectively.
While here, also move up `cleanupCallback` to match ELF / COFF.
Differential Revision: https://reviews.llvm.org/D97715
The new Darwin backend for LLD is now able to link reasonably large
real-world programs on x86_64. For instance, we have achieved
self-hosting for the X86_64 target, where all LLD tests pass when
building lld with itself on macOS. As such, we would like to make it the
default back-end.
The new port is now named `ld64.lld`, and the old port remains
accessible as `ld64.lld.darwinold`
This [annoucement email][1] has some context. (But note that, unlike
what the email says, we are no longer doing this as part of the LLVM 12
branch cut -- instead we will go into LLVM 13.)
Numerous mechanical test changes were required to make this change; in
the interest of creating something that's reviewable on Phabricator,
I've split out the boring changes into a separate diff (D95905). I plan to
merge its contents with those in this diff before landing.
(@gkm made the original draft of this diff, and he has agreed to let me
take over.)
[1]: https://lists.llvm.org/pipermail/llvm-dev/2021-January/147665.html
Reviewed By: #lld-macho, thakis
Differential Revision: https://reviews.llvm.org/D95204
Nico Weber