RuntimeError: one of the variables needed for gradient computation has been modified by an inplac

RuntimeError: one of the variables needed for gradient computation has been modified by an inplace operation: [torch.FloatTensor [128, 3, 4, 4]] is at version 2; expected version 1 instead. Hint: enable anomaly detection to find the operation that failed to compute its gradient, with torch.autograd.set_detect_anomaly(True).

在做stackGAN时候的问题，需要把前一个网络的G的输出作为下一层的输入，一开始的时候把两个网络合在一起写的，
iuputs-》G1-》output1，训练G1，output1->G2，训练G2
这时候是不能运行的，
报错：
RuntimeError: one of the variables needed for gradient computation has been modified by an inplace operation: [torch.FloatTensor [128, 3, 4, 4]] is at version 2; expected version 1 instead. Hint: enable anomaly detection to find the operation that failed to compute its gradient, with torch.autograd.set_detect_anomaly(True).
但是后面改成了
inuts->G1->output1 ，训练G1，inuts->G1(训练后的)->output1->G2，训练G2
感觉应该是变量是否存在梯度的问题，可能第一层的一开始的输出不能被梯度吧，需要再看看这些个变量的问题。

自用，不保证对错。