many warnings (practically safe but annoying) corrected

client/mysqladmin.cc:
  don't use the handler after it's closed
client/mysqlbinlog.cc:
  memory leak
client/mysqldump.c:
  many "ignore return value" warnings, one "NULL dereference"
cmd-line-utils/libedit/history.c:
  memory leak
include/my_base.h:
  cleanup
libmysql/libmysql.c:
  "return value ignored" warning
myisam/mi_delete.c:
  "return value ignored" warning
myisam/myisampack.c:
  "out-of-bound access" warning
myisam/sort.c:
  "double free" warning
mysys/default_modify.c:
  "double free" warning
mysys/mf_iocache2.c:
  "return value ignored" warnings
mysys/my_bitmap.c:
  s/return/DBUG_RETURN/
mysys/my_error.c:
  memory leak
server-tools/instance-manager/parse.cc:
  "NULL dereference" warning
sql-common/client.c:
  "NULL dereference" warning
sql/field.cc:
  deadcode, "NULL dereference", "uninitialized" warnings
sql/field.h:
  unused parameters removed from constructor
sql/ha_myisam.cc:
  "return value ignored" warnings
sql/item.cc:
  "return value ignored" warnings
  changed constructor
sql/item_func.cc:
  "return value ignored" warnings
sql/log_event.cc:
  uninitialized warning
sql/opt_range.cc:
  "double free" and uninitialized warnings
sql/opt_range.h:
  "return value ignored" warning
sql/repl_failsafe.cc:
  "return value ignored" warning
sql/set_var.cc:
  "return value ignored" warning
sql/slave.cc:
  "return value ignored" warnings
sql/slave.h:
  new prototype
sql/sql_acl.cc:
  deadcode and "NULL dereference" warnings
sql/sql_db.cc:
  "return value ignored" warning
sql/sql_handler.cc:
  "NULL dereference" warning
sql/sql_help.cc:
  "NULL dereference" warning
sql/sql_insert.cc:
  "return value ignored" warning
sql/sql_parse.cc:
  "return value ignored" warning
  one more DBUG_ASSERT
sql/sql_repl.cc:
  "return value ignored" and memory leak warnings
sql/sql_show.cc:
  "return value ignored" and "NULL dereference"  warnings
sql/sql_test.cc:
  "return value ignored" warning
sql/table.cc:
  memory leak
sql/uniques.cc:
  "return value ignored" warning
  endspaces deleted

sql/sql_test.cc

@@ -450,7 +450,7 @@ void mysql_print_status()
 
   calc_sum_of_all_status(&tmp);
   printf("\nStatus information:\n\n");
-  my_getwd(current_dir, sizeof(current_dir),MYF(0));
+  VOID(my_getwd(current_dir, sizeof(current_dir),MYF(0)));
   printf("Current dir: %s\n", current_dir);
   printf("Running threads: %d  Stack size: %ld\n", thread_count,
 	 (long) thread_stack);