The loop at the top of can_all_from_reach_with_flag() already accounts for `from->objects[i].item' being NULL, so it follows the cleanup loop should also account for a NULL `from_one'. I managed to segfault here on one of my giant, many-remote repos using `git fetch --negotiation-tip=... --negotiation-only' where the --negotiation-tip= argument was a glob which (inadvertently) captured more refs than I wanted. I have not reproduced this in a standalone test case. Signed-off-by: Eric Wong <e@xxxxxxxxx> --- Not sure if somebody who understands the code better can come up with a good standalone test case. I figure using the top loop as reference is sufficient evidence that this fix is needed. commit-reach.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/commit-reach.c b/commit-reach.c index 2e33c599a82..1d7056338b7 100644 --- a/commit-reach.c +++ b/commit-reach.c @@ -807,8 +807,12 @@ int can_all_from_reach_with_flag(struct object_array *from, clear_commit_marks_many(nr_commits, list, RESULT | assign_flag); free(list); - for (i = 0; i < from->nr; i++) - from->objects[i].item->flags &= ~assign_flag; + for (i = 0; i < from->nr; i++) { + struct object *from_one = from->objects[i].item; + + if (from_one) + from_one->flags &= ~assign_flag; + } return result; }