Improve fix for #69038

Author: laruence

ext/opcache/Optimizer/zend_optimizer.c

@@ -290,15 +290,24 @@ static void replace_tmp_by_const(zend_op_array *op_array,
 			 * and allows its reuse. The number of ZEND_CASE instructions
 			 * usually terminated by ZEND_FREE that finally kills the value.
 			 */
-			if (opline->opcode == ZEND_CASE) {
+			if (opline->opcode == ZEND_CASE || opline->opcode == ZEND_FREE) {
 				zend_op *m, *n;
 				int brk = op_array->last_brk_cont;
+				zend_bool in_case = 0;
 				while (brk--) {
 					if (op_array->brk_cont_array[brk].start <= (opline - op_array->opcodes) &&
 							op_array->brk_cont_array[brk].brk > (opline - op_array->opcodes)) {
+						in_case = 1;
 						break;
 					}
 				}
+
+				if (!in_case) {
+					MAKE_NOP(opline);
+					zval_dtor(val);
+					break;
+				}
+
 				m = opline;
 				n = op_array->opcodes + op_array->brk_cont_array[brk].brk + 1;
 				while (m < n) {
@@ -320,10 +329,6 @@ static void replace_tmp_by_const(zend_op_array *op_array,
 				}
 				zval_dtor(val);
 				break;
-			} else if (opline->opcode == ZEND_FREE) {
-				MAKE_NOP(opline);
-				zval_dtor(val);
-				break;
 			} else {				
 				update_op1_const(op_array, opline, val TSRMLS_CC);
 				break;

ext/opcache/tests/bug69038.phpt

@@ -39,7 +39,17 @@ function b($b = "bad") {
 	return $b;
 }
 var_dump(b());
+
+function c() {
+	switch (PHP_OS) {
+		default: return "bad";
+		case PHP_OS: return "okey";
+	}
+}
+
+var_dump(c());
 ?>
 --EXPECT--
 string(4) "okey"
 string(4) "okey"
+string(4) "okey"