diff --git a/src/xml.c b/src/xml.c
index 863c5d7..a9fb15e 100644
--- a/src/xml.c
+++ b/src/xml.c
@@ -22,6 +22,7 @@
  */
 #include <ctype.h>
 #include <malloc.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include "xml.h"
@@ -117,8 +118,6 @@ static size_t get_zero_terminated_array_elements(struct xml_node** nodes) {
  * @return true gdw. a == b
  */
 static _Bool xml_string_equals(struct xml_string* a, struct xml_string* b) {
-	_Bool const true = 1;
-	_Bool const false = 0;
 
 	if (a->length != b->length) {
 		return false;
diff --git a/test/test-xml.c b/test/test-xml.c
index 82c2f3f..7111a0e 100644
--- a/test/test-xml.c
+++ b/test/test-xml.c
@@ -20,13 +20,11 @@
  *
  *  3. This notice may not be removed or altered from any source distribution.
  */
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <xml.h>
 
-static _Bool true = 1;
-static _Bool false = 0;
-