these tasks have some shared data dependencies so they cannot be done
simultaneously. Future work should untangle these data dependencies so
that more can be done in parallel.
for now this commit ensures correctness by making linker input parsing
and codegen tasks part of the same queue.
Unfortunately it's not a complete solution, so a follow-up commit will
need to do something more drastic like not do the linker task queue at
the same time as codegen task queue.
From that point, it is possible to do more work at the same time but
that should be a separate branch. This one has gotten big enough.
If the "is darwin" check is moved below the libc_installation check
below, error.LibCInstallationMissingCrtDir is returned from
lci.resolveCrtPaths().
This should be revisited because it makes sense to check
libc_installation first even on darwin.
Anyway for now this more closely matches logic from master branch.
By making it a field of link.Elf, it is now accessible without a data
dependency on `files`, fixing a race condition with the codegen thread
and linker thread.
* Compilation.objects changes to Compilation.link_inputs which stores
objects, archives, windows resources, shared objects, and strings
intended to be put directly into the dynamic section. Order is now
preserved between all of these kinds of linker inputs. If it is
determined the order does not matter for a particular kind of linker
input, that item should be moved to a different array.
* rename system_libs to windows_libs
* untangle library lookup from CLI types
* when doing library lookup, instead of using access syscalls, go ahead
and open the files and keep the handles around for passing to the
cache system and the linker.
* during library lookup and cache file hashing, use positioned reads to
avoid affecting the file seek position.
* library directories are opened in the CLI and converted to Directory
objects, warnings emitted for those that cannot be opened.
The compiler defaults this value to off so that users whose system
shared libraries are all ELF files don't have to pay the cost of
checking every file to find out if it is a text file instead.
When a GNU ld script is encountered, the error message instructs users
about the CLI flag that will immediately solve their problem.
along with the relevant logic, making the libraries within subject to
the same search criteria as all the other libraries.
this unfortunately means doing file system access on all .so files when
targeting ELF to determine if they are linker scripts, however, I have a
plan to address this.
thread-sanitizer reports data races here when running test-link. I tried
only removing the ones that triggered races, but after 10 back and
forths with the compiler and tsan, I got impatient and removed all of
them.
next time, let's be sure the test suite runs tsan-clean before merging
any changes that add parallelism.
after this commit, `zig build test-link` completes without any tsan
warnings.
closes#21778
In end(), the freelist pointer is owned so the bare store would be ok.
However, there is a load in start() that can happen at the same time, if
another start() and end() pair grabs that same index.
I don't think this fixes#21663 actually because even if the data race
corrupts the value for `next`, the cmpxchg protects the value from being
stored there.
This was the cause of aarch64-windows shared libraries causing "bad image" errors
during load-time linking. I also re-enabled the tests that were surfacing this bug.
