aherrmann
Zig documentation generation occasionally fails with Zig >=0.12.0
See https://github.com/aherrmann/rules_zig/commit/fddc80dc8f5e184bb8ad6b5b8758ad3bef55d043
(06:27:04) ERROR: /Users/runner/work/rules_zig/rules_zig/e2e/workspace/zig-docs/BUILD.bazel:39:9: Generating Zig documentation for zig-docs/main.zig in bazel-out/darwin_arm64-fastbuild/bin/zig-docs/test.docs failed: (Exit 1): zig failed: error executing command (from target //zig-docs:test) external/zig_0.12.0_aarch64-macos/zig test --test-no-exec '-femit-docs=bazel-out/darwin_arm64-fastbuild/bin/zig-docs/test.docs' -fno-emit-bin -fno-emit-implib --zig-lib-dir ... (remaining 20 arguments skipped)
Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
error: unable to open directory '/var/tmp/zig-cache/b/cb9becf646f63b0941e2ca559689c01a/': FileNotFound
and
(06:28:49) ERROR: /Users/runner/work/rules_zig/rules_zig/zig/runfiles/BUILD.bazel:34:12: Generating Zig documentation for zig/runfiles/runfiles.zig in bazel-out/darwin_arm64-fastbuild/bin/zig/runfiles/lib.docs failed: (Exit 1): zig failed: error executing ZigBuildDocs command (from target //zig/runfiles:lib) external/_main~zig~zig_0.12.0_aarch64-macos/zig build-lib '-femit-docs=bazel-out/darwin_arm64-fastbuild/bin/zig/runfiles/lib.docs' -fno-emit-bin -fno-emit-implib --zig-lib-dir ... (remaining 14 arguments skipped)
Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
error: unable to open directory '/var/tmp/zig-cache/b/d9a5ae9513d8cf07f558187b0c1f9a5d/': FileNotFound
I was not able to reproduce this in a tmate session on a MacOS CI node. It's possible that this issue is caused by an inhermeticity introduced by the global shared cache.
Another instance occurred after adding a Bazel 7.0.0 pipeline and dropping Bazel 6 support.
(15:49:25) ERROR: /private/var/tmp/_bazel_runner/5ca2a14b857dddeda41464da6fe32452/external/rules_zig~override/zig/runfiles/BUILD.bazel:34:12: Generating Zig documentation for external/rules_zig~override/zig/runfiles/runfiles.zig in bazel-out/darwin_arm64-fastbuild/bin/external/rules_zig~override/zig/runfiles/lib.docs failed: (Exit 1): zig failed: error executing ZigBuildDocs command (from target @@rules_zig~override//zig/runfiles:lib) external/rules_zig~override~zig~zig_0.12.0_aarch64-macos/zig build-lib '-femit-docs=bazel-out/darwin_arm64-fastbuild/bin/external/rules_zig~override/zig/runfiles/lib.docs' -fno-emit-bin ... (remaining 16 arguments skipped)
Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
error: unable to open directory '/var/tmp/zig-cache/b/d9a5ae9513d8cf07f558187b0c1f9a5d/': FileNotFound
I have also observed this issue locally on Ubuntu 22.04
$ bazel clean --expunge; bazel build //... --noremote_accept_cached
...
ERROR: /home/aj/src/rules_zig/main/zig/runfiles/BUILD.bazel:34:12: Generating Zig documentation for zig/runfiles/runfiles.zig in zig/runfiles/lib.docs failed: (Exit 1): zig failed: error executing ZigBuildDocs command (from target //zig/runfiles:lib) external/_main~zig~zig_0.12.0_x86_64-linux/zig build-lib '-femit-docs=bazel-out/k8-fastbuild/bin/zig/runfiles/lib.docs' -fno-emit-bin -fno-emit-implib --zig-lib-dir ... (remaining 14 arguments skipped)
Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
error: unable to open directory '/tmp/zig-cache/b/20c09a1aeb3eb72fef452c05789e32ea/': FileNotFound
The error may be coming from https://github.com/ziglang/zig/blob/a685ab1499d6560c523f0dbce2890dc140671e43/src/Compilation.zig#L3755, introduced here. Perhaps a race between building the runfiles library and the runfiles library docs?
The hash path seems to be generated here for the builtins module, other modules elsewhere.
Reproduced locally on Ubuntu 22.04 with the following command
$ cd e2e/workspace
$ bazel clean; bazel test --build_tests_only --sandbox_tmpfs_path=/tmp -- //zig-docs:zig-docs //zig-docs:test
In contrast, the following succeeded more than three times in a row
$ cd e2e/workspace
bazel clean; bazel test --build_tests_only -- //zig-docs:zig-docs //zig-docs:test
The issue may be caused by an interplay between --sandbox_tmpfs_path=/tmp and the --(global-)cache-dir setting and --sandbox_add_mount_pair=/tmp.
Additionally passing the following flags seems to resolve the issue:
--repo_env=RULES_ZIG_CACHE_PREFIX=/var/tmp/bazel-zig-cache --sandbox_add_mount_pair=/var/tmp --sandbox_writable_path=/var/tmp
The issue seems to be gone since the update to rules_cc 0.1.1 and I can no longer reproduce it locally on Ubuntu 24.04.
The issue re-emerged on main, see this CI run, and on https://github.com/aherrmann/rules_zig/pull/436, see this CI run.