Regression: AOT DOMElement::setIdAttribute() — object::setidattribute / ExternalMethod segfault (ext/dom/element.c)

[PurHur]

Category

stdlib · php-src-strict · ext/dom AOT bridge · pillar 4

Problem

VM and JIT match Zend for DOMElement::setIdAttribute() + getElementById(). Thin user-script AOT does not:

Repro	Zend 8.2+ / VM / JIT	AOT (phpc build, 2026-08-09 @7bd8ddf2e2)
$el = $doc->documentElement->firstChild; $el->setIdAttribute('id', true)	works	compile: Call to undefined method object::setidattribute()
$el = $doc->createElement('a'); … $el->setIdAttribute('id', true)	works	compiles via ExternalMethod fallthrough → segfault (internal_N)

Root cause: setIdAttribute* is implemented in VmDomInstanceInvoke / VmDomJitDispatch but is not in DomInstanceMethodJit::USER_SCRIPT_DIRECT_METHODS, so :object receivers (child props) fail at compile and typed DOMElement receivers bind the null ExternalMethod stub.

php-src reference

• php/php-src ext/dom/element.c — dom_element_set_id_attribute*
• php/php-src ext/dom/php_dom.stub.php — DOMElement::setIdAttribute

PHP implementation target

• lib/JIT/DomInstanceMethodJit.php — add domelement::setidattribute{,ns,node} to user-script direct methods + registerKnownProxies
• lib/JIT.php — :object receiver ensureProxy/bind (peer #27108 attribute path)
• Reuse Call\DomInstanceMethod → VmDomInstanceInvoke (already dispatches setidattribute*); no new C

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
cat > /tmp/setid_aot.php <<'"'"'PHP'"'"'
<?php
$d = new DOMDocument();
$d->loadXML("<r><a id=\"x\"/><b id=\"x\"/></r>");
$a = $d->documentElement->firstChild;
$b = $a->nextSibling;
$a->setIdAttribute("id", true);
$b->setIdAttribute("id", true);
echo $d->getElementById("x")->nodeName, "\n";
PHP
php bin/vm.php /tmp/setid_aot.php
php bin/compile.php -o /tmp/setid_aot /tmp/setid_aot.php && /tmp/setid_aot'

Expect: a on VM and AOT (first-wins, #25275).

Done when

• AOT compiles + runs the firstChild repro (output a)
• AOT createElement typed path no longer segfaults
• Smallest compliance/repro guard; php-src-strict
• No new runtime/ C

[PurHur]

claim: PHP Compiler Ext — DOM & XML — starting this run

[PurHur]

Tried-first gates (before claim)

Gate	Result	Symptom
docker info	ok
php script/bootstrap-inventory.php --check	drift	live tree vs committed docs/bootstrap-inventory.md (MagicMethod* method-count); release-readiness still reports inventory ok
./script/release-readiness.sh --json	user_release_ready: **yes**	all quick gates ok; gen-0 provenance stale (115 lowering commits since cc281e13c) — #28998
helper-runtime-prelink	ok	371 fresh, 0 stale
north-star5-fast / vm-driver-probe / gen0-driver-functional	ok

Implementing AOT setIdAttribute* bridge on this issue.

[PurHur]

Merged in #29280.

Verification (local Docker):

• php bin/vm.php / jit.php / AOT compile.php on test/repro/issue_29257_dom_setidattribute_aot.php → a / c
• maintainer gap duplicate setIdAttribute AOT → a
• loadHTML getElementById AOT smoke → div
• inventory OK 7260/7260, spine coverage sync OK