Stdlib: unpack() named format:/string: — compile error vs Zend success (ext/standard/pack.c) #11590

Category

stdlib · php-src-strict · refs #1492

Problem

Calling unpack() with named parameters format: and string: must compile and run. Zend succeeds; this compiler rejects at compile time:

Cannot use positional argument after named argument

Positional unpack('n', $data) works.

Verified 2026-06-25 — test/repro/maintainer_gap_unpack_named_format_string.php prints unpack_named_ok=1 on Zend vs compile failure on VM.

php-src reference

• php/php-src ext/standard/pack.c — php_unpack

Repro

test/repro/maintainer_gap_unpack_named_format_string.php

php test/repro/maintainer_gap_unpack_named_format_string.php
php bin/vm.php test/repro/maintainer_gap_unpack_named_format_string.php

Implementation hints (PHP-in-PHP)

• Fix named-argument lowering for two-parameter builtins (format, string, optional offset)
• Shared lib/ call lowering; pair with Stdlib: file_put_contents() named context: — compile error vs Zend success (ext/standard/file.c) #11575 / Stdlib: stream_socket_client() named timeout/error_code — compile error vs Zend success (ext/standard/streamsfuncs.c) #11589 (same root cause class)

Done when (php-src-strict)

• Repro green on php bin/vm.php
• Named unpack() matches Zend