Re: git-merge segfault in 1.6.6 and master
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jan 22, 2010, 00:38 UTC
- Message-ID
- <7vaaw7j7mn.fsf@alter.siamese.dyndns.org>
- In-Reply-To
- <7vhbqfj8fy.fsf@alter.siamese.dyndns.org>
Junio C Hamano <gitster@pobox.com> writes:
Show 5 quoted lines
> After I stared at the code for more than two hours, I gave up trying to > diagnose this by myself. People more familiar with the merge-recursive > implementation might be able to help figuring this out and may prove my > suspicion wrong, but I have a feeling that without a fairly big rewrite > the code is unsalvageable.
In the meantime, I think applying this patch is the right thing to do.
-- >8 -- Subject: merge-recursive: do not return NULL only to cause segfault
merge-recursive calls write_tree_from_memory() to come up with a virtual tree, with possible conflict markers inside the blob contents, while merging multiple common ancestors down. It is a bug to call the function with unmerged entries in the index, even if the merge to come up with the common ancestor resulted in conflicts. Otherwise the result won't be expressible as a tree object.
We _might_ want to suggest the user to set GIT_MERGE_VERBOSITY to 5 and re-run the merge in the message. At least we will know which part of process_renames() or process_entry() functions is not correctly handling the unmerged paths, and it might help us diagnosing the issue.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- merge-recursive.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/merge-recursive.c b/merge-recursive.c index 1239647..cb53b01 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -202,14 +202,14 @@ struct tree *write_tree_from_memory(struct merge_options *o) if (unmerged_cache()) { int i; - output(o, 0, "There are unmerged index entries:"); + fprintf(stderr, "BUG: There are unmerged index entries:\n"); for (i = 0; i < active_nr; i++) { struct cache_entry *ce = active_cache[i]; if (ce_stage(ce)) - output(o, 0, "%d %.*s", ce_stage(ce), - (int)ce_namelen(ce), ce->name); + fprintf(stderr, "BUG: %d %.*s", ce_stage(ce), + (int)ce_namelen(ce), ce->name); } - return NULL; + die("Bug in merge-recursive.c"); } if (!active_cache_tree)