git log -p -m: document -m and honor --first-parent

diff --git a/shallow.c b/shallow.c
index dbd9f5ad0ac21e70fc3a095d8e2938f245c238d3..4d90eda19efe0a80c1cb39e8897ab3ed5e6fcf56 100644 (file)
--- a/shallow.c
+++ b/shallow.c
@@ -56,7 +56,7 @@ struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
                        if (i < heads->nr) {
                                commit = (struct commit *)
                                        deref_tag(heads->objects[i++].item, NULL, 0);
-                               if (commit->object.type != OBJ_COMMIT) {
+                               if (!commit || commit->object.type != OBJ_COMMIT) {
                                        commit = NULL;
                                        continue;
                                }
@@ -70,7 +70,8 @@ struct commit_list *get_shallow_commits(struct object_array *heads, int depth,
                                cur_depth = *(int *)commit->util;
                        }
                }
-               parse_commit(commit);
+               if (parse_commit(commit))
+                       die("invalid commit");
                commit->object.flags |= not_shallow_flag;
                cur_depth++;
                for (p = commit->parents, commit = NULL; p; p = p->next) {