merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 11 insertions, 7 deletions

diff --git a/third_party/git/alloc.c b/third_party/git/alloc.c
index 1c64c4dd1629..957a0af36264 100644
--- a/third_party/git/alloc.c
+++ b/third_party/git/alloc.c
@@ -99,23 +99,27 @@ void *alloc_object_node(struct repository *r)
 	return obj;
 }
 
-static unsigned int alloc_commit_index(struct repository *r)
+/*
+ * The returned count is to be used as an index into commit slabs,
+ * that are *NOT* maintained per repository, and that is why a single
+ * global counter is used.
+ */
+static unsigned int alloc_commit_index(void)
 {
-	return r->parsed_objects->commit_count++;
+	static unsigned int parsed_commits_count;
+	return parsed_commits_count++;
 }
 
-void init_commit_node(struct repository *r, struct commit *c)
+void init_commit_node(struct commit *c)
 {
 	c->object.type = OBJ_COMMIT;
-	c->index = alloc_commit_index(r);
-	c->graph_pos = COMMIT_NOT_FROM_GRAPH;
-	c->generation = GENERATION_NUMBER_INFINITY;
+	c->index = alloc_commit_index();
 }
 
 void *alloc_commit_node(struct repository *r)
 {
 	struct commit *c = alloc_node(r->parsed_objects->commit_state, sizeof(struct commit));
-	init_commit_node(r, c);
+	init_commit_node(c);
 	return c;
 }