fix #649

Former-commit-id: e6120a937ddb4f3c0b9bcb2466742f5cf4f77f8c

src/llmtuner/tuner/core/parser.py

@@ -156,10 +156,9 @@ def get_train_args(
         and finetuning_args.finetuning_type == "lora"
     ):
         logger.warning("`ddp_find_unused_parameters` needs to be set as False for LoRA in DDP training.")
-        training_args.ddp_find_unused_parameters = False
-
-    if training_args.optim == "adamw_hf":
-        training_args.optim = "adamw_torch" # suppress warning
+        training_args_dict = training_args.to_dict()
+        training_args_dict.update(dict(ddp_find_unused_parameters=False))
+        training_args = Seq2SeqTrainingArguments(**training_args_dict)
 
     if (
         training_args.resume_from_checkpoint is None
@@ -172,7 +171,9 @@ def get_train_args(
             raise ValueError("Output directory already exists and is not empty. Use `overwrite_output_dir`.")
 
         if last_checkpoint is not None:
-            training_args.resume_from_checkpoint = last_checkpoint
+            training_args_dict = training_args.to_dict()
+            training_args_dict.update(dict(resume_from_checkpoint=last_checkpoint))
+            training_args = Seq2SeqTrainingArguments(**training_args_dict)
             logger.info(
                 "Resuming from checkpoint. Change `output_dir` or use `overwrite_output_dir` to avoid."
             )