ci: disable opcache.protect_memory for phpt suite — incompatible with threaded workers (#93)#108
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…ith threaded workers) (#93) opcache.protect_memory=1 (a run-tests default) guards the SHM with process-global mprotect toggled OUTSIDE the compile lock. The true-async worker pool runs workers as threads in one address space, so one worker's SHM_PROTECT flips the page read-only under another worker's in-flight SHM write during concurrent compilation on pool rotation — an intermittent SIGBUS (seen as the 053 flake on macOS ARM64). opcache itself notes "mprotect() is process-global and races" (ZendAccelerator.c). Not a production concern: the directive defaults off and the actual compilation is serialized by zend_shared_alloc_lock; only a benign last_used timestamp write is left unlocked. Override it to 0 in every phpt run.
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CoverageTotal lines: 75.45% → 75.44% (-0.01 pp)
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Root cause of the
053-hot-reload-watchermacOS flakeopcache.protect_memory=1(a run-tests default) protects the opcache SHM with process-globalmprotect, toggled viaSHM_UNPROTECT/SHM_PROTECToutside the compile lock (persistent_compile_file,ZendAccelerator.c).The true-async worker pool runs workers as threads in one address space. On hot-reload rotation, fresh workers concurrently recompile the changed file into the shared SHM. One worker's
SHM_PROTECTflips the page read-only process-wide while another worker is mid-write → SIGBUS (KERN_PROTECTION_FAILURE). Backtrace (captured via the new crash-report CI step):opcache itself acknowledges this: "mprotect() is process-global and races" (
ZendAccelerator.c).Why this is safe
opcache.protect_memorydefaults to0; thenSHM_(UN)PROTECTare no-ops.zend_shared_alloc_lock(atsrm_mutex_lockunder ZTS), so no SHM corruption.last_usedtimestamp — a benign torn write.So
protect_memory=1is a debug/CI diagnostic that is architecturally incompatible with the threaded-worker model; it produces false crashes, not real ones.Change
Pass
-d opcache.protect_memory=0to every phpt run (linux, macos, windows, debug-macos-workers, chaos). Verified locally that run-tests appends the user-dafter its hardcodedprotect_memory=1, so the last one wins → child gets0.