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Stdlib: strcmp()/strncmp() null operands — empty-string coercion (#11261) #11270

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Merged
PurHur merged 1 commit into from
Jun 24, 2026
Merged

Stdlib: strcmp()/strncmp() null operands — empty-string coercion (#11261) #11270

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30 changes: 20 additions & 10 deletions ext/standard/VmString.php
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Original file line number Diff line number Diff line change
Expand Up @@ -807,16 +807,26 @@ public static function strncmp(string $a, string $b, int $length): int
}
$lenA = self::byteLength($a);
$lenB = self::byteLength($b);
$compare = $length;
if ($compare > $lenA) {
$compare = $lenA;
}
if ($compare > $lenB) {
$compare = $lenB;
}
for ($i = 0; $i < $compare; ++$i) {
$ordA = self::byteOrd($a[$i]);
$ordB = self::byteOrd($b[$i]);
for ($i = 0; $i < $length; ++$i) {
if ($i >= $lenA) {
if ($i >= $lenB) {
return 0;
}
if (0 === $lenA) {
return -1;
}
$ordA = 0;
$ordB = self::byteOrd($b[$i]);
} elseif ($i >= $lenB) {
if (0 === $lenB) {
return 1;
}
$ordA = self::byteOrd($a[$i]);
$ordB = 0;
} else {
$ordA = self::byteOrd($a[$i]);
$ordB = self::byteOrd($b[$i]);
}
if ($ordA !== $ordB) {
return $ordA - $ordB;
}
Expand Down
23 changes: 19 additions & 4 deletions ext/standard/strcmp.php
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Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
use PHPCompiler\JIT\JitStringBuiltinArg;
use PHPCompiler\JIT\JitStringCompare;
use PHPCompiler\JIT\Variable as JITVariable;
use PHPCompiler\VM\InternalStrictArg;
use PHPLLVM\Value;

final class strcmp extends Internal
Expand All @@ -26,8 +27,8 @@ public function execute(Frame $frame): void
if (2 !== count($frame->calledArgs)) {
throw new \LogicException('strcmp() requires exactly two arguments');
}
$a = VmString::requireStringBuiltinArg($frame->calledArgs[0], 'strcmp', 0, 'string1');
$b = VmString::requireStringBuiltinArg($frame->calledArgs[1], 'strcmp', 1, 'string2');
$a = self::vmStringArg($frame, 0, 'string1');
$b = self::vmStringArg($frame, 1, 'string2');
if (null === $frame->returnVar) {
return;
}
Expand All @@ -42,9 +43,23 @@ public function call(Context $context, JITVariable ...$args): Value
if (2 !== count($args)) {
throw new \LogicException('strcmp() requires exactly two arguments');
}
$left = JitStringBuiltinArg::lowerRequiredString($context, $args[0], 'strcmp', 0, 'string1');
$right = JitStringBuiltinArg::lowerRequiredString($context, $args[1], 'strcmp', 1, 'string2');
$left = JitStringBuiltinArg::lower($context, $args[0], 'strcmp', 0, 'string1');
$right = JitStringBuiltinArg::lower($context, $args[1], 'strcmp', 1, 'string2');

return JitStringCompare::strcmp($context, $left, $right);
}

private static function vmStringArg(Frame $frame, int $argIndex, string $paramName): string
{
if (InternalStrictArg::isCallerStrict($frame)) {
return InternalStrictArg::requireString($frame, $argIndex, 'strcmp', $paramName)->toString();
}

return VmString::coerceStringBuiltinArgNoObject(
$frame->calledArgs[$argIndex],
'strcmp',
$argIndex,
$paramName
);
}
}
23 changes: 19 additions & 4 deletions ext/standard/strncmp.php
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Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
use PHPCompiler\JIT\JitLongArg;
use PHPCompiler\JIT\JitStringBuiltinArg;
use PHPCompiler\JIT\Variable as JITVariable;
use PHPCompiler\VM\InternalStrictArg;
use PHPLLVM\Value;

/**
Expand All @@ -27,8 +28,8 @@ final class strncmp extends Internal
public function execute(Frame $frame): void
{
$this->requireExactArgCount($frame, 'strncmp', 3);
$a = VmString::requireStringBuiltinArg($frame->calledArgs[0], 'strncmp', 0, 'string1');
$b = VmString::requireStringBuiltinArg($frame->calledArgs[1], 'strncmp', 1, 'string2');
$a = self::vmStringArg($frame, 0, 'string1');
$b = self::vmStringArg($frame, 1, 'string2');
if (null === $frame->returnVar) {
return;
}
Expand All @@ -44,8 +45,8 @@ public function call(Context $context, JITVariable ...$args): Value
if (!$this->requireExactJitArgCount($context, $args, 'strncmp', 3)) {
return $context->getTypeFromString('int64')->constInt(0, false);
}
$p0 = $this->stringDataPtr($context, JitStringBuiltinArg::lowerRequiredString($context, $args[0], 'strncmp', 0, 'string1'));
$p1 = $this->stringDataPtr($context, JitStringBuiltinArg::lowerRequiredString($context, $args[1], 'strncmp', 1, 'string2'));
$p0 = $this->stringDataPtr($context, JitStringBuiltinArg::lower($context, $args[0], 'strncmp', 0, 'string1'));
$p1 = $this->stringDataPtr($context, JitStringBuiltinArg::lower($context, $args[1], 'strncmp', 1, 'string2'));
$length = $context->builder->zExt(
$context->builder->trunc(
JitLongArg::lower($context, $args[2], 'strncmp() length'),
Expand All @@ -58,4 +59,18 @@ public function call(Context $context, JITVariable ...$args): Value

return $context->builder->sExt($raw, $i64);
}

private static function vmStringArg(Frame $frame, int $argIndex, string $paramName): string
{
if (InternalStrictArg::isCallerStrict($frame)) {
return InternalStrictArg::requireString($frame, $argIndex, 'strncmp', $paramName)->toString();
}

return VmString::coerceStringBuiltinArgNoObject(
$frame->calledArgs[$argIndex],
'strncmp',
$argIndex,
$paramName
);
}
}
11 changes: 11 additions & 0 deletions test/compliance/cases/stdlib/strcmp_null_coerce.phpt
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Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
--TEST--
stdlib strcmp()/strncmp() null operands coerce without strict_types (#11261, ext/standard/string.c)
--FILE--
<?php
echo strcmp(null, 'a'), "\n";
echo strncmp(null, 'a', 1), "\n";
echo strcmp('a', null), "\n";
--EXPECT--
-1
-1
1
5 changes: 5 additions & 0 deletions test/repro/maintainer_gap_strcmp_null_coerce.php
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Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
<?php

echo strcmp(null, 'a'), "\n";
echo strncmp(null, 'a', 1), "\n";
echo strcmp('a', null), "\n";