Stdlib: vsprintf() rejects inline array literal — LogicException not formatted string (ext/standard/sprintf.c)

[PurHur]

Category

stdlib · compile lowering · php-src-strict

Problem

vsprintf('%d', [7]) fails at runtime when the second argument is an inline array literal, while the same values in a variable work. Zend returns the formatted string.

Call	Zend	VM today
vsprintf('%d', [7])	'7'	LogicException: second argument must be an array
$a=[7]; vsprintf('%d',$a)	'7'	'7' (OK)

Same class of bug as literal-null / inline-[] mis-binding (#9305, #9563, #9349).

php-src reference

• php/php-src ext/standard/sprintf.c — PHP_FUNCTION(vsprintf)
• Zend tests: ext/standard/tests/strings/vsprintf*.phpt

Repro

php test/repro/maintainer_vsprintf_inline_array.php
php bin/vm.php test/repro/maintainer_vsprintf_inline_array.php
php bin/vm.php -r '\$a=[7]; echo vsprintf("%d", \$a);'  # control: OK

Scope (PHP-in-PHP)

• Fix builtin argument marshalling for inline array literals in lib/ compiler / VM call path
• ext/standard sprintf family if argc guards assume non-literal arrays

Done when (php-src-strict)

• Repro prints 7 on VM
• Regression guard; JIT/AOT agree when sprintf builtins lowered

Links

• Regression: builtin calls with null literal arguments mis-bind parameters (array_column/array_search/in_array, ext/standard/array.c) #9305, Regression: nested array-return builtin in call argument evaluates to null (ext/standard/array.c, streams.c) #9547, php-in-php: JIT StringFormatJit — route sprintf/printf/number_format through VmSprintf not libc LLVM (#1492) #9131 (php-in-php sprintf JIT)
• North star Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492

[PurHur]

claim: worker-lane-c — starting this run

[PurHur]

claim released: repro already green on master — maintainer_vsprintf_inline_array.php prints 7/7 on VM matching Zend.

[PurHur]

claim: worker-lane-c — starting this run

[PurHur]

Unclaiming — repro green on master (2026-07-12): php bin/vm.php -r 'echo vsprintf("%d", [7]);' prints 7; vsprintf_basic.phpt passes.

[PurHur]

Closed by lane-C hygiene (#10241): inline array literal repro green — vsprintf('%d', [7]) prints 7 on VM. Verified in Docker 2026-07-13.