大虾 请教

新手有问题想请教下
NET "q<0>" LOC=P24;
NET "q<1>" LOC=P25;
NET "q<2>" LOC=P26;
NET "q<3>" LOC=P27;
MapLib:30 - LOC constraint P25 on q<1> is invalid: No such site on the
   device. To bypass this error set the environment variable 'XIL_MAP_LOCWARN'.
想请教下是什么原因
还和环境变量有关系吗?