diff --git a/.gitattributes b/.gitattributes
index 7985aa57bc658..e6680bc2caae2 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -14,6 +14,7 @@
 /sklearn/svm/libsvm.c -diff
 /sklearn/svm/libsvm_sparse.c -diff
 /sklearn/tree/_tree.c -diff
+/sklearn/tree/_utils.c -diff
 /sklearn/utils/arraybuilder.c -diff
 /sklearn/utils/arrayfuncs.c -diff
 /sklearn/utils/graph_shortest_path.c -diff