Fixed bug #76094 (Access violation when using opcache)

Author: laruence

NEWS

@@ -6,6 +6,9 @@ PHP                                                                        NEWS
   . Fixed bug #76088 (ODBC functions are not available by default on Windows).
     (cmb)
 
+- Opcache:
+  . Fixed bug #76094 (Access violation when using opcache). (Laruence)
+
 - Standard:
   . Fixed bug #74139 (mail.add_x_header default inconsistent with docs). (cmb)
 

ext/opcache/Optimizer/dce.c

@@ -356,7 +356,8 @@ static zend_bool dce_instr(context *ctx, zend_op *opline, zend_ssa_op *ssa_op) {
 
 	if ((opline->op1_type & (IS_VAR|IS_TMP_VAR))&& !is_var_dead(ctx, ssa_op->op1_use)) {
 		if (!try_remove_var_def(ctx, ssa_op->op1_use, ssa_op->op1_use_chain, opline)) {
-			if (ssa->var_info[ssa_op->op1_use].type & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_REF)) {
+			if (ssa->var_info[ssa_op->op1_use].type & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_REF)
+				&& opline->opcode != ZEND_CASE) {
 				free_var = ssa_op->op1_use;
 				free_var_type = opline->op1_type;
 			}

ext/opcache/tests/bug76094.phpt

@@ -0,0 +1,26 @@
+--TEST--
+Bug #76094 (Access violation when using opcache)
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+function MetaType($t)
+{
+
+	switch (strtoupper($t)) {
+	case PHP_INT_MAX :
+		return 1;
+	case 0:
+	default:
+		return 0;
+	}
+}
+
+var_dump(MetaType("aa"));
+?>
+--EXPECT--
+int(0)