Repository: huggingface/transformers
Pull request: remove FSDP prefix when using save_pretrained with FSDP2

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Changed files:
filename: src/transformers/modeling_utils.py
patch: @@ -4022,7 +4022,8 @@ def save_pretrained(
         model_to_save.config.dtype = str(dtype).split(".")[1]
 
         # Attach architecture to the config
-        model_to_save.config.architectures = [model_to_save.__class__.__name__]
+        # When using FSDP2, unwrapping is a noop, so the model name doesn't change back to the original model name
+        model_to_save.config.architectures = [model_to_save.__class__.__name__.removeprefix("FSDP")]
 
         # If we have a custom model, we copy the file defining it in the folder and set the attributes so it can be
         # loaded from the Hub.