CI: Default BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=1 in ci-local (#1846 follow-up)

[PurHur]

Problem

#1846 ✅ landed script/bootstrap-selfhost-lib-spine-vm-smoke.sh — the M2 spine AOT binary runs bin/vm.php -r with PHP_COMPILER_VM_SPINE_SMOKE=1 and prints vm-spine-ok. CI wiring exists in script/ci-common.sh but BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE defaults to 0 in script/ci-defaults.env.

Full ./script/ci-local.sh therefore validates native link of the spine bundle but not the real vm.php driver path on that binary — a gap on the road to M5 (#1521).

Goal

1. Default BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=1 in script/ci-defaults.env once Self-host M2: land final 3 ext/standard Vm* units in compiler_lib_spine_smoke (578→586) #1821 spine units are green (584→586)
2. Opt-out: BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=0 for spine-only link PRs
3. Update docs/local-ci-matrix.md and phpc doctor --gates
4. Include in DevEx: make north-star2-verify presenter gate (self-host M0–M4) #1865 north-star2-verify step 4

Acceptance criteria

• LLVM tail of ci-local.sh runs VM spine smoke by default on master
• test/unit/CiScriptsTest.php + BootstrapLibSpineVmSmokeTest aligned with default
• Failure message points to Self-host M2: land final 3 ext/standard Vm* units in compiler_lib_spine_smoke (578→586) #1821 if Vm* units missing from bundle

Dependencies

• Self-host M2: land final 3 ext/standard Vm* units in compiler_lib_spine_smoke (578→586) #1821 — final 3 Vm* units in compiler_lib_spine_smoke
• Self-host M2: native bin/vm.php -r smoke on compiler_lib_spine bundle #1846 ✅ — script + Makefile target exist

Verify

BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=1 make bootstrap-selfhost-lib-spine-vm-smoke
# Docker:
docker run --rm -v "$(pwd):/compiler" -w /compiler php-compiler:22.04-dev \
  env BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=1 make bootstrap-selfhost-lib-spine-vm-smoke

Links

• Self-host M2: native bin/vm.php -r smoke on compiler_lib_spine bundle #1846 ✅, Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492, ROADMAP 🗺️ ROADMAP: Self-host + web-capable PHP subset (living) #78

[PurHur]

PR #1875 flips BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE default to 1 with docs + unit tests. Spine VM smoke script did not complete in harness Docker (JIT compile error during link); merge after ./script/bootstrap-selfhost-lib-spine-vm-smoke.sh is green locally.

[PurHur]

PM / PR queue (batch 79):

Open PR #1875 implements this issue. Do not merge yet:

• PR body reports harness Docker failure during spine link (PHPLLVM\\LLVMAbstract\\Type\\Struct::getElementType() in lib/JIT/Builtin/Type/String_.php).
• Re-run ./script/bootstrap-selfhost-lib-spine-vm-smoke.sh green before merge; then full ./script/ci-local.sh llvm tail.

Opt-out for spine-only PRs: BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=0 ./script/ci-local.sh

Depends on #1846 ✅ (script exists); spine bundle 589/593 per #1872 ✅.

[PurHur]

PM (batch 80): Blocked on #1880 / PR #1884. Do not merge #1875 until spine link + bootstrap-selfhost-lib-spine-vm-smoke.sh exit 0 on LLVM tail. Opt-out remains BOOTSTRAP_LIB_SPINE_VM_SMOKE_GATE=0 for iteration.