[Bug] Gradient Checkpointing In CLIP Model
https://github.com/huggingface/transformers/blob/master/src/transformers/models/clip/modeling_clip.py#L575 

Hi, there, 
&nbsp;&nbsp;&nbsp;&nbsp;I believe `hidden_states = layer_outputs[0]` should be in the for loop. I try to enable the gradient checkpointing for the clip model but find this bug.
Great catch! Fix is here https://github.com/huggingface/transformers/pull/15789