Compiler: fix stream_context_create([]) after @mkdir misbind (#16205)

lib/Compiler.php

@@ -8192,7 +8192,10 @@ private function inheritErrorSuppressExpressionSlots(Block $suppressCompiled, Bl
                     ) {
                         continue;
                     }
-                    if ($this->errorSuppressEndBlockCallArgHasTrailingHoistedScalarProducer($endCompiled, $endChild, (int) $argIndex)) {
+                    if (
+                        $this->errorSuppressEndBlockCallArgHasTrailingHoistedScalarProducer($endCompiled, $endChild, (int) $argIndex)
+                        || $this->errorSuppressEndBlockCallArgHasTrailingHoistedArrayProducer($endCompiled, $endChild, (int) $argIndex)
+                    ) {
                         continue;
                     }
                     // First dead temp in the outer call is the @ inner value (#15916, #10302).
@@ -28693,10 +28696,55 @@ private function errorSuppressEndBlockInnerResultSlotForCallArg(
         if ($this->errorSuppressEndBlockCallArgHasTrailingHoistedScalarProducer($block, $cfgCallOp, $argIndex)) {
             return null;
         }
+        if ($this->errorSuppressEndBlockCallArgHasTrailingHoistedArrayProducer($block, $cfgCallOp, $argIndex)) {
+            return null;
+        }
 
         return $this->errorSuppressEndBlockInnerResultSlot($block);
     }
 
+    /**
+     * Trailing hoisted Array_ before a post-@ call feeds this dead-temp arg (#16205).
+     */
+    private function errorSuppressEndBlockCallArgHasTrailingHoistedArrayProducer(
+        Block $block,
+        Op $cfgCallOp,
+        int $argIndex
+    ): bool {
+        if (null === $block->orig || !property_exists($cfgCallOp, 'args') || !\is_array($cfgCallOp->args)) {
+            return false;
+        }
+        $callArg = $cfgCallOp->args[$argIndex] ?? null;
+        if (!$callArg instanceof Operand || $this->isEmbeddedCallLiteralArg($callArg)) {
+            return false;
+        }
+        if (!$this->callArgIsDeadInlineTemporary($callArg)) {
+            return false;
+        }
+        $arrayProducer = $this->inlineArrayProducerImmediatelyBeforeCfgCall($cfgCallOp, $block);
+        if (!$arrayProducer instanceof Op\Expr\Array_) {
+            return false;
+        }
+        if (
+            null !== $arrayProducer->result
+            && $this->operandsReferToSameVariable($arrayProducer->result, $callArg)
+        ) {
+            return true;
+        }
+        $nonEmbeddedArgIndices = [];
+        foreach ($cfgCallOp->args as $i => $candidate) {
+            if (!$this->isEmbeddedCallLiteralArg($candidate)) {
+                $nonEmbeddedArgIndices[] = (int) $i;
+            }
+        }
+        $producerOrdinal = array_search($argIndex, $nonEmbeddedArgIndices, true);
+        if (false === $producerOrdinal) {
+            return false;
+        }
+
+        return 0 === $producerOrdinal;
+    }
+
     /**
      * Trailing hoisted true/false/null before a post-@ call feeds this dead-temp arg (#15916).
      *
@@ -28779,7 +28827,7 @@ private function errorSuppressEndBlockCallArgHasTrailingHoistedScalarProducer(
     /**
      * True when an outer call in a post-@ block consumes the suppressed inner expression (#10336, #15916).
      *
-     * Standalone `@mkdir(); stream_context_create(null)` must not wire hoisted null to mkdir's return slot.
+     * Standalone `@mkdir(); stream_context_create(null|[])` must not wire hoisted literal to mkdir's return slot.
      */
     private function callInErrorSuppressEndBlockUsesInnerResultAsArg(Block $block, Op $cfgCallOp): bool
     {

test/compliance/cases/stdlib/stream_context_create_empty_after_mkdir.phpt

@@ -0,0 +1,10 @@
+--TEST--
+stream_context_create([]) after @mkdir — empty literal stays array (#16205, ext/standard/streams.c)
+--FILE--
+<?php
+$dir = sys_get_temp_dir() . '/phpc_stream_ctx_' . getmypid();
+@mkdir($dir);
+$ctx = stream_context_create([]);
+echo is_resource($ctx) ? "ok\n" : "fail\n";
+--EXPECT--
+ok

test/repro/maintainer_gap_stream_context_create_after_mkdir.php

@@ -0,0 +1,6 @@
+<?php
+
+$dir = sys_get_temp_dir() . '/phpc_stream_ctx_' . getmypid();
+@mkdir($dir);
+$ctx = stream_context_create([]);
+echo is_resource($ctx) ? "ok\n" : "fail\n";

test/unit/ErrorSuppressInlineReturnSlotTest.php

@@ -233,4 +233,57 @@ public function testStandaloneSuppressStatementDoesNotAliasHoistedNullCallArg():
             'hoisted null must not alias unrelated @mkdir return slot'
         );
     }
+
+    public function testStandaloneSuppressStatementDoesNotAliasHoistedEmptyArrayCallArg(): void
+    {
+        $code = <<<'PHP'
+<?php
+@mkdir('/tmp/phpc_suppress_hoist_gap');
+$ctx = stream_context_create([]);
+PHP;
+        $runtime = new Runtime();
+        $block = $runtime->parseAndCompile($code, 'suppress_then_hoisted_empty_array.php');
+
+        $suppressReturnSlot = null;
+        $streamContextSendSlot = null;
+        $walk = static function (Block $b) use (&$walk, &$suppressReturnSlot, &$streamContextSendSlot): void {
+            $inSuppress = null !== $b->orig && $b->orig instanceof \PHPCfg\ErrorSuppressBlock;
+            $inEnd = null !== $b->orig && 1 === \count($b->orig->parents) && $b->orig->parents[0] instanceof \PHPCfg\ErrorSuppressBlock;
+            $pendingInit = false;
+            foreach ($b->opCodes as $op) {
+                if (OpCode::TYPE_FUNCCALL_INIT === $op->type) {
+                    $pendingInit = true;
+                    continue;
+                }
+                if ($pendingInit && OpCode::TYPE_FUNCCALL_EXEC_RETURN === $op->type) {
+                    if ($inSuppress) {
+                        $suppressReturnSlot = $op->arg1;
+                    }
+                    $pendingInit = false;
+                    continue;
+                }
+                if ($pendingInit && OpCode::TYPE_FUNCCALL_EXEC_NORETURN === $op->type) {
+                    $pendingInit = false;
+                    continue;
+                }
+                if (OpCode::TYPE_ARG_SEND === $op->type && $inEnd && null === $streamContextSendSlot) {
+                    $streamContextSendSlot = $op->arg1;
+                }
+                foreach ([$op->block1, $op->block2, $op->block3] as $sub) {
+                    if ($sub instanceof Block) {
+                        $walk($sub);
+                    }
+                }
+            }
+        };
+        $walk($block);
+
+        self::assertNotNull($suppressReturnSlot, 'suppress mkdir return slot');
+        self::assertNotNull($streamContextSendSlot, 'stream_context_create arg send slot');
+        self::assertNotSame(
+            $suppressReturnSlot,
+            $streamContextSendSlot,
+            'hoisted [] must not alias unrelated @mkdir return slot'
+        );
+    }
 }