[azooz2003-bit]

Summary

ios-simulator-build failed twice on #24572 (cmux9s-mac-mini-glaeda-4, cmuxs-mac-mini-5-glaeda-2) with:

error: file '…/cmuxios-unit-tests/<runner>/Build/Products/Debug-iphonesimulator/include/ghostty.h' has been modified since the module file '…/SwiftExplicitPrecompiledModules/GhosttyNextKit-*.pcm' was built

The owned runners keep this DerivedData per runner, so a push rebuilds only what changed. But each run copies ghostty.h again with a new mtime, which leaves the explicit PCMs from the previous run stale. Base pushes skip this lane, which is why only PRs that touch Packages/iOS or ios/ see it.

On exactly that error, the step now clears the three module caches and runs once more. Any other failure fails as before.

Changelog

none

Tests

• YAML parses. The if ! run_tests form keeps set -e from stopping on the first failure.
• I didn't run this lane by hand. cmux mobile: newlines in the chat composers; tap any file to preview it #24572's next ios-simulator-build exercises it after this merges.

Observed / Not run

• Observed: the error on cmux mobile: newlines in the chat composers; tap any file to preview it #24572, runs 40016826289 and 40024227335.
• Not run: actionlint (not installed locally); the hosted ci-guards job runs it.

🤖 Generated with Claude Code

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Summary by cubic

Retries the CmuxiOS unit test step once when a runner's cached precompiled modules are stale, so the lane stops failing on the "has been modified since the module file" error.

• The per-runner DerivedData keeps explicit precompiled modules; each run copies ghostty.h again with a new mtime, leaving them stale.
• On that exact error, clears SwiftExplicitPrecompiledModules, ExplicitPrecompiledModules, and ModuleCache.noindex, then runs the tests once more.
• Any other failure still fails the job as before.

^{Written for commit 59e8907. Summary will update on new commits.}

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review 59e8907: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr24600 -f ref=ci-ios-stale-pcm-retry -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); no finished base run on 79c784a to compare; do not merge until green; see lane-rules

[azooz2003-bit]

Review (fresh correctness subagent): SHIP. Under set -euo pipefail, if ! run_tests passes the exit status through, and any non-matching failure exits 1. The watchdog reopens its log with wb, so the grep reads the run it is checking. The three cleared paths are the explicit-module caches under -derivedDataPath, and the SPM cache is left alone. Nothing is masked: a retry needs that exact compile error, and no tests ran before it. Nit: a retry can double the step's time. That's resolved: the stale-module failure stops in the first minute of compiling (42 s on #24572), so a second run fits in the 20-minute limit.

[teamleaderleo]

Bead cx-f6j98 created for this PR by the cmux coordinator.

[blacksmith-sh]

Found 10 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmpk7cl7asz/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmpvzuqiclf/summary-missing.json (live):/summary-missing.json (live):	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs
convention violations found (ERROR lines above)./ convention violations found (ERROR lines above).	View Logs
test_base_passes (main.NoticesPairTests.test_base_passes)/ test_base_passes (main.NoticesPairTests.test_base_passes)	View Logs
test_targets_outside_the_app_go_to_the_mac_canary (main.SwiftCanaryFleetCoverage.te st_targets_outside_the_app_go_to_the_mac_canary)/ test_targets_outside_the_app_go_to_the_mac_canary (main.SwiftCanaryFleetCoverage.te st_targets_outside_the_app_go_to_the_mac_canary)	View Logs
the committed export failed: check-daemon-capabilities-fresh: plans/cmux-next/ daemon-capabilities.json is stale:	View Logs

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[azooz2003-bit]

Verified on this PR's own ios-simulator-build, rerun on cmuxs-mac-mini-5-glaeda-2:

• The first run stopped on ghostty.h has been modified since the module file …GhosttyNextKit-*.pcm was built.
• The step logged stale precompiled modules … clearing them and running again.
• The retry passed ("Test run with 19 tests in 4 suites passed"), and the job ended success.

Remaining reds are base findings: cmux-next checks (the ThinScroller files in CmuxNextDesign) and nightly-guards (no xcodebuild on that runner).