Prevent attempts of compile-time evaluation of invalid operators (e.g. division/modulo by zero and shift by negative number)

Zend/tests/bug69957.phpt

@@ -0,0 +1,84 @@
+--TEST--
+Bug #69957 (Different ways of handling div/mod by zero)
+--FILE--
+<?php
+
+try {
+	$divisor = 0;
+	$result = 1 / $divisor;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "Variable div\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+try {
+	$divisor = 0;
+	$result = 1 % $divisor;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "\nVariable mod\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+try {
+	$result = 1 / 0;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "\nLiteral div\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+try {
+	$result = 1 % 0;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "\nLiteral mod\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+try {
+	$result = 1 / 0.0;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "\nDouble div\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+try {
+	$result = 1 % 0.0;
+	var_dump($result);
+} catch (Throwable $t){
+	echo "\nDouble mod\n";
+	printf("Type: %s\n", get_class($t));
+	printf("Message: %s\n", $t->getMessage());
+}
+
+?>
+--EXPECTF--
+Warning: Division by zero in %sbug69957.php on line %d
+float(INF)
+
+Variable mod
+Type: Exception
+Message: Division by zero
+
+Warning: Division by zero in %sbug69957.php on line %d
+float(INF)
+
+Literal mod
+Type: Exception
+Message: Division by zero
+
+Warning: Division by zero in %sbug69957.php on line %d
+float(INF)
+
+Double mod
+Type: Exception
+Message: Division by zero
+

Zend/zend_compile.c

@@ -5625,17 +5625,12 @@ static inline zend_bool zend_try_ct_eval_binary_op(zval *result, uint32_t opcode
 	binary_op_type fn = get_binary_op(opcode);
 
 	/* don't evaluate division by zero at compile-time */
-	if (opcode == ZEND_DIV) {
-		convert_scalar_to_number(op2);
-		if (Z_TYPE_P(op2) == IS_LONG) {
-			if (Z_LVAL_P(op2) == 0) {
-				return 0;
-			}
-		} else if (Z_TYPE_P(op2) == IS_DOUBLE) {
-			if (Z_DVAL_P(op2) == 0.0) {
-				return 0;
-			}
-		}
+	if ((opcode == ZEND_DIV || opcode == ZEND_MOD) &&
+	    zval_get_long(op2) == 0) {
+		return 0;
+	} else if ((opcode == ZEND_SL || opcode == ZEND_SR) &&
+	    zval_get_long(op2) < 0) {
+		return 0;
 	}
 
 	fn(result, op1, op2);