client/mysqltest.c:
  undef popen prior to redefining it to avoid compiler warning
  cast len argument to replace_dynstr_append_mem to int.  This should be ok because the 
  replace_dynstr_append method uses strlen to accomplish the same thing.
myisam/mi_create.c:
  cast myisam_block_size down to uint16 to match the struct element block_length
mysys/default.c:
  add (char*) cast to make compiler happy
mysys/my_handler.c:
  add (my_bool) cast to make compiler happy