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Foundation: Zend gen-0 of compiler_minimal hangs after compiletofile_done (link gate never finishes) #31726
Description
Category
Foundation: · bootstrap-selfhost-link · Zend gen-0 fallback hang
Problem
When committed prelinked/bootstrap-gen0 is lowering-fingerprint stale, ./script/bootstrap-selfhost-gate.sh link falls back to Zend AOT of test/selfhost/compiler_minimal/main.php. Under PHP_COMPILER_DOCKER_MEM=16g the emit succeeds (build/selfhost runs and prints compiler_minimal bundle OK) and progress reaches runtime_standalone_compiletofile_done, but php bin/compile.php never exits — it stays at ~100% CPU / ~4.7 GiB RSS for 15+ minutes after the artifact is stable. The link gate therefore never reaches the smoke loop or prints bootstrap-selfhost-link: OK.
Probed 2026-08-17 on master @81c0eecf41 (post-#31725).
| Step | Result |
|---|---|
| Default 10g docker mem | Fail-fast #31714 (expected) |
| Remount 16g + Zend gen-0 | Artifact written + runs OK; compile.php hung after compiletofile_done |
Manual ./build/selfhost |
compiler_minimal bundle OK (exit 0) |
php-src reference
N/A (compiler pipeline / AOT teardown). Related history: #21925 (intermittent post-OK abort), #31714 (16g remount).
PHP implementation target
bin/compile.php/lib/AOT//lib/JIT/path afterruntime_standalone_compiletofile_done— must exit 0 once-oartifact is linked- Optionally
script/bootstrap-resolve-compile-invoke.sh/ link gate: treat stable executable + progress marker as success with a bounded wait (do not hang forever) - No new
runtime/*.c
Repro
docker info >/dev/null
# ensure gen-0 fingerprint is stale (normal tip drift)
PHP_COMPILER_DOCKER_MEM=16g PHP_COMPILER_DOCKER_MEM_SWAP=16g \
./script/docker-exec.sh -- bash -lc './script/bootstrap-selfhost-gate.sh link'
# observe: build/selfhost becomes runnable while php bin/compile.php continues at 100% CPUDone when
- Zend gen-0 of
compiler_minimalexits 0 shortly after writing a runnable-obinary -
./script/bootstrap-selfhost-gate.sh linkat 16g printsbootstrap-selfhost-link: OK(or native gen-0 path when fingerprint fresh) - No fingerprint restamp; php-src-strict N/A (tooling/pipeline)
Activity
PurHur commentedon Aug 17, 2026
claim: lane-B compile/link implementer — starting this run (bootstrap fallback; first red was #31714@10g, then Zend hang after successful emit)
PurHur commentedon Aug 17, 2026
claim: lane-B implementer — continuing #31726 (post-compiletofile_done hang; investigating _exit before LLVM/PHP teardown)
Foundation: fast-exit selfhost AOT before LLVM context teardown (#31726…
PurHur commentedon Aug 17, 2026
Merged #31741.
Fix:
_exit(0)at end ofRuntime::standalone()after successful selfhostcompileToFile, before JIT Context destructor (LLVM teardown hang / #21925 abort).Verified:
SelfhostAotFastExitTestOK; tinytest/selfhost/AOT exits with progressruntime_standalone_fast_exit.PurHur commentedon Aug 17, 2026
Merged #31742
Verification
./script/phpunit.sh --filter SelfhostAotFastExitTest— OK (6)rc=0in ~14s afterruntime_standalone_compiletofile_donePHP_COMPILER_DOCKER_MEM=16g PHP_COMPILER_DOCKER_MEM_SWAP=16g ./script/docker-exec.sh -- bash -lc './script/bootstrap-selfhost-gate.sh link'→bootstrap-selfhost-link: OK/compiler_minimal bundle OK(clean_exit; watchdog not needed)Fix: warm libc
_exitbefore LLVM; exit immediately after successful selfhost emit; Zend invoke watchdog as backup.Foundation: fast-exit Zend gen-0 after selfhost AOT emit (#31726)
Foundation: fast-exit Zend gen-0 after selfhost AOT emit (#31726) (#3…
PurHur commentedon Aug 17, 2026
Follow-up merged: #31742 (on top of #31741)
Hardening beyond the initial
_exitinRuntime::standalone:lib/AOT/AotEmitFastExitwarms libc_exitvialibc.so.6before LLVM FFI growsbootstrap_compile_invoke_zendpost-emit hang watchdog (BOOTSTRAP_SELFHOST_POST_EMIT_GRACE_SEC)Full link gate (this worker):
PHP_COMPILER_DOCKER_MEM=16g PHP_COMPILER_DOCKER_MEM_SWAP=16g ./script/docker-exec.sh -- bash -lc './script/bootstrap-selfhost-gate.sh link'→
bootstrap-selfhost-link: OK/compiler_minimal bundle OK/EXIT:0Split-TU: fast-exit after SPINE_CHUNK AOT emit (#36155) (#36234)