diff --git a/mpc.c b/mpc.c
index 99de0d9..be9d88b 100644
--- a/mpc.c
+++ b/mpc.c
@@ -122,13 +122,14 @@ void mpc_err_string_cat(char *buffer, int *pos, int *max, char const *fmt, ...)
   va_end(va);
 }
 
-static char char_unescape_buffer[3];
+static char char_unescape_buffer[4];
 
 static const char *mpc_err_char_unescape(char c) {
   
   char_unescape_buffer[0] = '\'';
   char_unescape_buffer[1] = ' ';
   char_unescape_buffer[2] = '\'';
+  char_unescape_buffer[3] = '\0';
   
   switch (c) {