diff --git a/src/ld65/exports.c b/src/ld65/exports.c
index 937b3379e..d1eb20df3 100644
--- a/src/ld65/exports.c
+++ b/src/ld65/exports.c
@@ -687,6 +687,8 @@ static char GetAddrSizeCode (unsigned char AddrSize)
         case ADDR_SIZE_LONG:    return 'L';
         default:
             Internal ("Invalid address size: %u", AddrSize);
+	    /* NOTREACHED */
+	    return '-';
     }
 }