1

Work around a known race in Zig build system

More information in the commit message and
https://github.com/ziglang/zig/issues/14815
This commit is contained in:
Motiejus Jakštys 2023-03-20 10:25:41 +02:00 committed by Motiejus Jakštys
parent 97a4846b58
commit 9779650a78

View File

@ -45,16 +45,15 @@ return_code={return_code}
stderr={stderr}
stdout={stdout}
You most likely hit a rare but known race in Zig SDK. Congratulations?
You stumbled into a problem with Zig SDK that bazel-zig-cc was not able to fix.
Please file a new issue to github.com/uber/bazel-zig-cc with:
- Full output of this Bazel run, including the Bazel command.
- Version of the Zig SDK if you have a non-default.
- Version of bazel-zig-cc.
We are working on fixing it with Zig Software Foundation. If you are curious,
feel free to follow along in https://github.com/ziglang/zig/issues/14815
There isn't much to do now but wait. Now apply the following workaround:
$ rm -fr {cache_prefix}
$ <... re-run your command ...>
... and proceed with your life.
Note: this *may* have been https://github.com/ziglang/zig/issues/14815, for
which bazel-zig-cc has a workaround and you may have been "struck by lightning"
three times in a row.
"""
def toolchains(
@ -199,20 +198,50 @@ def _zig_repository_impl(repository_ctx):
"launcher.zig",
] + (["-static"] if os == "linux" else [])
# The elaborate code below is a workaround for ziglang/zig#14815:
# Sometimes, when Zig's cache is empty, compiling the launcher may fail
# with `error: FileNotFound`. The remedy is to clear the cache and try
# again. Until this change, we have been asking users to clear the Zig
# cache themselves and re-run the Bazel command.
#
# We can do better than that: if we detect the launcher failed, we can
# purge the zig cache and retry the compilation. It will be retried for up
# to two times.
launcher_success = True
launcher_err_msg = ""
for _ in range(3):
# Do not remove the cache_prefix itself, because it is not controlled
# by this script. Instead, clear the cache subdirs that we know Zig
# populates.
zig_cache_dirs = ["h", "o", "tmp", "z"]
if not launcher_success:
print("Launcher compilation failed. Clearing %s/{%s} and retrying" %
(cache_prefix, ",".join(zig_cache_dirs)))
for d in zig_cache_dirs:
repository_ctx.delete(paths.join(cache_prefix, d))
ret = repository_ctx.execute(
compile_cmd,
working_directory = "tools",
environment = compile_env,
)
if ret.return_code != 0:
if ret.return_code == 0:
launcher_success = True
break
launcher_success = False
full_cmd = [k + "=" + v for k, v in compile_env.items()] + compile_cmd
fail(_compile_failed.format(
launcher_err_msg = _compile_failed.format(
compile_cmd = " ".join(full_cmd),
return_code = ret.return_code,
stdout = ret.stdout,
stderr = ret.stderr,
cache_prefix = cache_prefix,
))
)
if not launcher_success:
fail(launcher_err_msg)
exe = ".exe" if os == "windows" else ""
for target_config in target_structs():