sequencer: fix a memory leak in do_reset()

Fix a memory leak introduced in 9055e40 (sequencer: introduce new
commands to reset the revision, 2018-04-25), which called
setup_unpack_trees_porcelain() without a corresponding call to
clear_unpack_trees_porcelain().

This introduces a change in behavior in that we now start calling
clear_unpack_trees_porcelain() even without having called the
setup_unpack_trees_porcelain(). That's OK, that clear function, like
most others, will accept a zero'd out struct.

This inches us closer to passing various tests in
"t34*.sh" (e.g. "t3434-rebase-i18n.sh"), but because they have so many
other memory leaks in revisions.c this doesn't make any test file or
even a single test pass.

Signed-off-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: avar

sequencer.c

@@ -3646,7 +3646,7 @@ static int do_reset(struct repository *r,
 	struct lock_file lock = LOCK_INIT;
 	struct tree_desc desc = { 0 };
 	struct tree *tree;
-	struct unpack_trees_options unpack_tree_opts;
+	struct unpack_trees_options unpack_tree_opts = { 0 };
 	int ret = 0;
 
 	if (repo_hold_locked_index(r, &lock, LOCK_REPORT_ON_ERROR) < 0)
@@ -3683,7 +3683,6 @@ static int do_reset(struct repository *r,
 		}
 	}
 
-	memset(&unpack_tree_opts, 0, sizeof(unpack_tree_opts));
 	setup_unpack_trees_porcelain(&unpack_tree_opts, "reset");
 	unpack_tree_opts.head_idx = 1;
 	unpack_tree_opts.src_index = r->index;
@@ -3723,6 +3722,7 @@ static int do_reset(struct repository *r,
 	if (ret < 0)
 		rollback_lock_file(&lock);
 	strbuf_release(&ref_name);
+	clear_unpack_trees_porcelain(&unpack_tree_opts);
 	return ret;
 }