diff --git a/ext/dom/document.c b/ext/dom/document.c
index e281e65ce07..6db729535d3 100644
--- a/ext/dom/document.c
+++ b/ext/dom/document.c
@@ -752,7 +752,7 @@ PHP_METHOD(DOMDocument, importNode)
 	xmlDocPtr docp;
 	xmlNodePtr nodep, retnodep;
 	dom_object *intern, *nodeobj;
-	bool recursive = 0;
+	bool recursive = false;
 
 	if (zend_parse_parameters(ZEND_NUM_ARGS(), "O|b", &node, dom_node_class_entry, &recursive) == FAILURE) {
 		RETURN_THROWS();
@@ -802,7 +802,7 @@ static void dom_modern_document_import_node(INTERNAL_FUNCTION_PARAMETERS, zend_c
 	xmlDocPtr docp;
 	xmlNodePtr nodep, retnodep;
 	dom_object *intern, *nodeobj;
-	bool recursive = 0;
+	bool recursive = false;
 
 	if (zend_parse_parameters(ZEND_NUM_ARGS(), "O|b", &node, node_ce, &recursive) != SUCCESS) {
 		RETURN_THROWS();
diff --git a/ext/dom/element.c b/ext/dom/element.c
index dbab9313015..9f4e6d357c0 100644
--- a/ext/dom/element.c
+++ b/ext/dom/element.c
@@ -1019,7 +1019,7 @@ static void dom_set_attribute_ns_legacy(dom_object *intern, xmlNodePtr elemp, ch
 			name_valid = xmlValidateName(BAD_CAST localname, 0);
 			if (name_valid != 0) {
 				errorcode = INVALID_CHARACTER_ERR;
-				stricterror = 1;
+				stricterror = true;
 			} else {
 				attr = xmlHasProp(elemp, BAD_CAST localname);
 				if (attr != NULL && attr->type != XML_ATTRIBUTE_DECL) {
diff --git a/ext/dom/node.c b/ext/dom/node.c
index dba4bb8db87..61e693fa776 100644
--- a/ext/dom/node.c
+++ b/ext/dom/node.c
@@ -1463,7 +1463,7 @@ PHP_METHOD(DOMNode, cloneNode)
 	zval *id;
 	xmlNode *n, *node;
 	dom_object *intern;
-	bool recursive = 0;
+	bool recursive = false;
 
 	id = ZEND_THIS;
 	if (zend_parse_parameters(ZEND_NUM_ARGS(), "|b", &recursive) == FAILURE) {