Regression: trim/ltrim/rtrim 3rd arg TypeError under PROFILE≥8.4 — Zend ArgumentCountError (re-#23224, ext/standard/string.c) #28230

Category

bug · php-src-strict · phantom $mode · pillar 4 (sibling #28202 StringTrimMode enum; re-#23224)

Problem

Under PHP_COMPILER_PROFILE=8.4, trim(" x ", " ", true) throws TypeError: trim(): Argument #3 ($mode) must be of type StringTrimMode, bool given — proving a phantom 3rd $mode parameter wired to the non-existent StringTrimMode enum (#28202).

Zend/php-src arity is 2 (string $string, string $characters = " \n\r\t\v\0"); excess args are ArgumentCountError: trim() expects at most 2 arguments, 3 given. Same for ltrim / rtrim.

Verified 2026-08-06 vs php:8.4-cli (8.4.24).

Removing the phantom enum (#28202) should naturally restore arity-2 ArgumentCountError; this ticket tracks the call-site observable until that lands (or an explicit arity guard).

php-src reference

• php/php-src ext/standard/string.stub.php — trim/ltrim/rtrim (2 params, no mode)
• php/php-src ext/standard/string.c — php_trim

PHP implementation target

• ext/standard/ — drop $mode / StringTrimMode from trim family stubs + VM handlers (coordinate with Regression: StringTrimMode phantom on PROFILE≥8.4 — absent from php-src (re-#7283, ext/standard/string.stub.php) #28202)
• Ensure 3-arg calls → ArgumentCountError like Zend

Repro

./script/docker-exec.sh -- bash -lc 'export PHP_COMPILER_PROFILE=8.4
php -r '"'"'file_put_contents("/tmp/t.php", "<?php\ntry { trim(\" x \", \" \", true); } catch (Throwable \$e) { echo get_class(\$e), \":\", \$e->getMessage(), PHP_EOL; }\necho \"enum=\", enum_exists(\"StringTrimMode\") ? \"1\" : \"0\", PHP_EOL;\n");'"'"'
php bin/vm.php /tmp/t.php'

Done when

• trim/ltrim/rtrim reject 3rd positional arg with Zend-shaped ArgumentCountError
• No StringTrimMode parameter type in Reflection or TypeError path
• Regression: StringTrimMode phantom on PROFILE≥8.4 — absent from php-src (re-#7283, ext/standard/string.stub.php) #28202 enum absence satisfied (or closed together)
• php-src-strict; no php-compiler-strict shortcut