Repository: huggingface/transformers
Pull request: guard on model.eval when using torch.compile + FSDP2

# What does this PR do?
If the model is torch.compile(d) and if we're using FSDP2, after `self._wrap_model(...)` is called, the model is actually the `model.forward` function, so it's not possible to call `.eval()` on it


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Changed files:
filename: src/transformers/trainer.py
patch: @@ -4412,7 +4412,8 @@ def evaluation_loop(
             logger.info("  Num examples: Unknown")
         logger.info(f"  Batch size = {batch_size}")
 
-        model.eval()
+        if hasattr(model, "eval") and callable(model.eval):
+            model.eval()
         if hasattr(self.optimizer, "eval") and callable(self.optimizer.eval):
             self.optimizer.eval()