Language: @ inside closure skips error_get_last() — Zend records silenced Warning (zend_errors.c)

[PurHur]

Category

Language · php-src-strict / @ silence + error_get_last

Problem

@$undef inside a compiled closure (or the same pattern in a user function) is silent on both Zend and VM (good), but Zend still records the warning in error_get_last() while VM/JIT leave error_get_last() null.

File-scope @$undef already updates error_get_last() (control). Builtin @preg_match('/(/', …) inside a closure already records the message (control; #13662). This is the language undefined-variable + ZEND_BEGIN_SILENCE path in a nested frame.

Probed 2026-08-18 @ 87cba84dc2 — Zend 8.2.32 vs php bin/vm.php / php bin/jit.php.

Repro	Zend 8.2.32	VM/JIT
closure: error_clear_last(); @$undef; error_get_last()	type=2 Undefined variable $undef	type=none (null)
file-scope @$undef then error_get_last()	type=2 same message	type=2 ✓
closure: unsileced $undef then error_get_last()	records; line = inner	records; line = call site (see sibling nested-frame line issue)
closure: @preg_match('/(/','a')	records preg Compilation failed	records ✓

php-src reference

• php/php-src Zend/zend_execute.c — ZEND_BEGIN_SILENCE / EG(error_reporting) for @; silenced errors still populate EG(last_error)
• php/php-src Zend/zend_builtin_functions.c — PHP_FUNCTION(error_get_last) reads EG(last_error)
• php/php-src Zend/zend_errors.c — zend_error stores last error even when reporting is 0

PHP implementation target

• lib/VM.php — silenced undefined-variable in a callee frame must still snapshot into the error_get_last buffer (same as file-scope @)
• lib/VM/ErrorReporter.php (or existing silence helpers) — @ suppresses display, not last-error storage
• No new runtime/*.c

Repro

./script/docker-exec.sh -- bash -lc 'php bin/vm.php test/repro/maintainer_gap_error_get_last_at_undef_closure.php'
./script/docker-exec.sh -- bash -lc 'php bin/jit.php test/repro/maintainer_gap_error_get_last_at_undef_closure.php'
./script/docker-exec.sh -- bash -lc 'php test/repro/maintainer_gap_error_get_last_at_undef_closure.php'  # Zend baseline

<?php
error_reporting(E_ALL);
error_clear_last();
$fn = function () {
    @ $undef;
    $e = error_get_last();
    echo 'type=', $e['type'] ?? 'none', "\n";
    echo 'msg=', $e['message'] ?? 'none', "\n";
};
$fn();

Done when

• VM/JIT: @$undef inside a closure/function updates error_get_last() to E_WARNING Undefined variable $undef (Zend); no user-visible Warning
• File-scope @$undef and @preg_match malformed inside a closure unchanged (already green)
• Compliance .phpt under test/compliance/cases/language/
• php-src-strict; no php-compiler-strict shortcut

[PurHur]

claim: PHP Runtime → PHP — starting this run

Implementing php-src-strict: silenced undefined-variable inside a compiled closure/function must still populate error_get_last() (Zend EG(last_error) even when reporting is 0). PHP path in lib/VM.php / ErrorReporter — no new runtime/*.c.

[PurHur]

merged: #32056 (bf1a18dfa1)

php-src-strict: @$undef inside a closure/function now records error_get_last() as Zend (type=2, Undefined variable $undef) with no user-visible Warning. PHP path in lib/VM.php (ErrorSuppress named-local ZEND_CHECK_UNDEFINED_VAR while silenced) and lib/JIT/UndefinedVariableHelper.php (TYPE_ASSIGN RHS guard). No new runtime/*.c.

Verification:

• php bin/vm.php / php bin/jit.php test/repro/maintainer_gap_error_get_last_at_undef_closure.php match Zend
• ./script/phpunit.sh --filter ErrorControlOperatorTest OK (11)
• ./script/phpunit.sh test/compliance/ErrorSuppressJITTest.php OK (4), including at_silence_undef_closure_error_get_last.phpt