diff --git a/tests/fdtdump.dts b/tests/fdtdump.dts
index b9d917b..b83b7df 100644
--- a/tests/fdtdump.dts
+++ b/tests/fdtdump.dts
@@ -23,6 +23,7 @@
 	randomnode {
 		string =  "foo", "stuff";
 		bytes = [61 62 63 64 65];
+		nbytes = [80 ff];
 		child {
 		};
 	};
diff --git a/util.c b/util.c
index 9d65226..cbb945b 100644
--- a/util.c
+++ b/util.c
@@ -349,7 +349,6 @@ int utilfdt_decode_type(const char *fmt, int *type, int *size)
 void utilfdt_print_data(const char *data, int len)
 {
 	int i;
-	const char *p = data;
 	const char *s;
 
 	/* no data, don't print */
@@ -376,6 +375,7 @@ void utilfdt_print_data(const char *data, int len)
 			       i < (len - 1) ? " " : "");
 		printf(">");
 	} else {
+		const unsigned char *p = (const unsigned char *)data;
 		printf(" = [");
 		for (i = 0; i < len; i++)
 			printf("%02x%s", *p++, i < len - 1 ? " " : "");