Regression: str_replace()/str_ireplace(null $search) still coerce under PROFILE=8.4 (ext/standard/string.c) #20173

Category

stdlib · php-src-strict · PHP 8.4 null→TypeError · ext/standard

Problem

Under PHP_COMPILER_PROFILE=8.4, str_replace(null, $replace, $subject) / str_ireplace(null, …) still coerce $search to '' and return $subject unchanged. $subject null already TypeErrors; $search must too. php-src 8.4 rejects null for non-nullable array|string search args with TypeError.

php-src reference

• php/php-src ext/standard/string.c — php_str_replace_common / Z_PARAM_ARRAY_OR_STR for $search
• PHP 8.4 forward: null to non-nullable internal string/array args → TypeError

PHP implementation target

• ext/standard/ str_replace / str_ireplace builtins (VM + JIT helpers)
• Reuse shared 8.4 null guard (VmString::coerceZparamStrBuiltinArg / array-or-string variant) for $search — PHP-in-PHP only, no new C

Repro

./script/docker-exec.sh -- bash -lc 'cat > /tmp/str_replace_null84.php <<'"'"'PHP'"'"'
<?php
foreach (["str_replace" => fn() => str_replace(null, "b", "hay"), "str_ireplace" => fn() => str_ireplace(null, "b", "Hay")] as $n => $fn) {
  try { echo "$n COERCED ", var_export($fn(), true), "\n"; }
  catch (Throwable $e) { echo "$n ", get_class($e), "\n"; }
}
PHP
PHP_COMPILER_PROFILE=8.4 php bin/vm.php /tmp/str_replace_null84.php'

Expected: both TypeError. Today: COERCED 'hay' / COERCED 'Hay'.

Done when

• str_replace(null, …) / str_ireplace(null, …) throw TypeError under PHP_COMPILER_PROFILE=8.4 on VM
• JIT/AOT agree when in scope
• Compliance .phpt under test/compliance/cases/string/
• Default/8.2 profile still coerces like Zend 8.2
• php-src-strict; no php-compiler-strict shortcut