From 4468d4435c44d50723e96e3416f8b5da97a1806f Mon Sep 17 00:00:00 2001 From: SZEDER Gábor Date: Sun, 27 Jan 2019 14:08:32 +0100 Subject: object_as_type: initialize commit-graph-related fields of 'struct commit' MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When the commit graph and generation numbers were introduced in commits 177722b344 (commit: integrate commit graph with commit parsing, 2018-04-10) and 83073cc994 (commit: add generation number to struct commit, 2018-04-25), they tried to make sure that the corresponding 'graph_pos' and 'generation' fields of 'struct commit' are initialized conservatively, as if the commit were not included in the commit-graph file. Alas, initializing those fields only in alloc_commit_node() missed the case when an object that happens to be a commit is first looked up via lookup_unknown_object(), and is then later converted to a 'struct commit' via the object_as_type() helper function (either calling it directly, or as part of a subsequent lookup_commit() call). Consequently, both of those fields incorrectly remain set to zero, which means e.g. that the commit is present in and is the first entry of the commit-graph file. This will result in wrong timestamp, parent and root tree hashes, if such a 'struct commit' instance is later filled from the commit-graph. Extract the initialization of 'struct commit's fields from alloc_commit_node() into a helper function, and call it from object_as_type() as well, to make sure that it properly initializes the two commit-graph-related fields, too. With this helper function it is hopefully less likely that any new fields added to 'struct commit' in the future would remain uninitialized. With this change alloc_commit_index() won't have any remaining callers outside of 'alloc.c', so mark it as static. Signed-off-by: SZEDER Gábor Signed-off-by: Junio C Hamano --- object.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'object.c') diff --git a/object.c b/object.c index 51c4594515..675cb8902b 100644 --- a/object.c +++ b/object.c @@ -164,8 +164,9 @@ void *object_as_type(struct repository *r, struct object *obj, enum object_type return obj; else if (obj->type == OBJ_NONE) { if (type == OBJ_COMMIT) - ((struct commit *)obj)->index = alloc_commit_index(r); - obj->type = type; + init_commit_node(r, (struct commit *) obj); + else + obj->type = type; return obj; } else { -- cgit v1.2.3