diff --git a/src/Json.c b/src/Json.c
index 32cc6f9..d96b89a 100644
--- a/src/Json.c
+++ b/src/Json.c
@@ -397,7 +397,7 @@ JsonDecodeString(FILE * in)
     size_t len;
     size_t allocated;
     char *str;
-    char c;
+    int c;
     char a[5];
 
     unsigned long utf8;