diff --git a/degesch.c b/degesch.c
index 30c1645..744cd87 100644
--- a/degesch.c
+++ b/degesch.c
@@ -1891,7 +1891,7 @@ formatter_parse_mirc (struct formatter *self, const char *s)
 
 	FORMATTER_ADD_RESET (self);
 
-	char c;
+	unsigned char c;
 	while ((c = *s++))
 	{
 		if (buf.len && c < 0x20)