From 576755e6006108aa6a3d90f0cd228f314d6d52e1 Mon Sep 17 00:00:00 2001
From: Arthur <48595927+ArthurZucker@users.noreply.github.com>
Date: Tue, 30 May 2023 17:12:14 +0200
Subject: [PATCH] [from_pretrained] imporve the error message when
 `_no_split_modules` is not defined (#23861)

* Better warning

* Update src/transformers/modeling_utils.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* format line

---------

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
---
 src/transformers/modeling_utils.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/transformers/modeling_utils.py b/src/transformers/modeling_utils.py
index 38be4e736a7a09..2dbe5d43829b99 100644
--- a/src/transformers/modeling_utils.py
+++ b/src/transformers/modeling_utils.py
@@ -2734,7 +2734,10 @@ def from_pretrained(cls, pretrained_model_name_or_path: Optional[Union[str, os.P
                 target_dtype = torch.int8
 
             if model._no_split_modules is None:
-                raise ValueError(f"{model.__class__.__name__} does not support `device_map='{device_map}'` yet.")
+                raise ValueError(
+                    f"{model.__class__.__name__} does not support `device_map='{device_map}'`. To implement support, the model"
+                    "class needs to implement the `_no_split_modules` attribute."
+                )
             no_split_modules = model._no_split_modules
             if device_map not in ["auto", "balanced", "balanced_low_0", "sequential"]:
                 raise ValueError(