Self-host M3: helloworld_m3_emit execute — parseAndCompile returned null (HelloWorld emit TU) #2567

Milestone

M3 — largest emit translation unit on the ladder (parent #1492 / #1937)

Problem

With M3 native emit flags, the HelloWorld emit helper links (build/selfhost-helloworld-emit) but strict execute fails:

helloworld_compile_smoke: parseAndCompile returned null (CFG/compile spine)
helloworld_compile_smoke: native emit failed at phase=parseAndCompile
bootstrap-selfhost-helloworld-probe: emit_path=zend_fallback_would_be_used

This TU calls Runtime::parseAndCompileEmitSmoke via the native spine symbol parseandcompileemitsmoke (see BootstrapCompileSmokeM3Emit.php). Smaller TUs fail the same way (#2559, #2561); fix the shared spine in #2563 first, then verify HelloWorld.

Scope

Repro

./script/docker-exec.sh -- bash -lc '
  source script/php-env.sh
  BOOTSTRAP_M3_LINK_COMPILE_DRIVER=1 \
  BOOTSTRAP_M3_COMPILE_DRIVER_REAL_LOWERING=1 \
  BOOTSTRAP_M3_RUNTIME_COMPILE=1 \
  BOOTSTRAP_M3_HELLOWORLD_STRICT=1 \
  ./script/bootstrap-selfhost-helloworld-probe.sh
'
# Today: exit 1, parseAndCompile returned null

Partial (Zend fallback allowed):

make bootstrap-selfhost-helloworld
# emit_path=zend partial; native run OK (Hello World)

Done when

• Strict probe exits 0 with emit_path=native (no zend_fallback_would_be_used)
• Native emit produces build/helloworld-aot without bin/compile.php fallback
• Unblocks Self-host M3: make HelloWorld strict (no Zend emit fallback) the default gate after emit_path=native #2522 (M3 strict default-on) and M4 gen-2 (Self-host M4: bootstrap_loop gen-2 native emit — parseAndCompile returned null #2560)

Labels

suggested: self-host, bootstrap, IMPORTANT

Epic #1492 · Root fix #2563 · Smaller TUs #2559 · #2561 · Downstream #2540 (execute segfault if spine green)