trying to remove Windows compiler warnings (Miguel, could you please check if it's better now?)

innobase/eval/eval0eval.c:
  explicit cast
sql/ha_innodb.cc:
  removed unused variable

innobase/eval/eval0eval.c

@@ -725,7 +725,7 @@ eval_predefined(
 				uint_val = (ulint) int_val;
 			}
 			for (tmp = int_len; uint_val > 0; uint_val /= 10) {
-				data[--tmp] = '0' + (uint_val % 10);
+				data[--tmp] = '0' + (byte)(uint_val % 10);
 			}
 		}
 

sql/ha_innodb.cc

@@ -4780,7 +4780,6 @@ innodb_show_status(
 /*===============*/
 	THD*	thd)	/* in: the MySQL query thread of the caller */
 {
-        char*           buf;
         Protocol        *protocol= thd->protocol;
 	trx_t*		trx;