MFH: fix #43596 (array_slice(): $length arg ignored when it is 0)

ext/standard/array.c

@@ -2113,12 +2113,13 @@ PHP_FUNCTION(array_slice)
 	zend_bool preserve_keys = 0; /* Whether to preserve keys while copying to the new array or not */
 	int		 num_in,		/* Number of elements in the input array */
 			 pos;			/* Current position in the array */
+	zval	*z_length;
 	char *string_key;
 	uint string_key_len;
 	ulong num_key;
 	HashPosition hpos;
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "al|lb", &input, &offset, &length, &preserve_keys) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "al|z/b", &input, &offset, &z_length, &preserve_keys) == FAILURE) {
 		return;
 	}
 
@@ -2126,7 +2127,10 @@ PHP_FUNCTION(array_slice)
 	num_in = zend_hash_num_elements(Z_ARRVAL_P(input));
 
 	/* We want all entries from offset to the end if length is not passed or is null */
-	if (length == 0) {
+	if (ZEND_NUM_ARGS() >= 3 && Z_TYPE_P(z_length) != IS_NULL) {
+		convert_to_long(z_length);
+		length = Z_LVAL_P(z_length);
+	} else {
 		length = num_in;
 	}