replace: die early if replace ref already exists

diff --git a/commit.c b/commit.c
index 0f28902bc351fef9d621cfe290f887921ec779c4..f4793316a21fe5f3ee1932f7e24cf4ab0920b04c 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -721,7 +721,7 @@ void sort_in_topological_order(struct commit_list **list, enum rev_sort_order so
 
 /* merge-base stuff */
 
-/* bits #0..15 in revision.h */
+/* Remember to update object flag allocation in object.h */
 #define PARENT1                (1u<<16)
 #define PARENT2                (1u<<17)
 #define STALE          (1u<<18)