*/
 
 #include "cache.h"
+#include "config.h"
 #include "parse-options.h"
 #include "builtin.h"
 #include "lockfile.h"
                        DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
                opts.detect_rename = DIFF_DETECT_RENAME;
                diff_setup_done(&opts);
-               diff_tree_sha1(head->hash, new_head->hash, "", &opts);
+               diff_tree_oid(head, new_head, "", &opts);
                diffcore_std(&opts);
                diff_flush(&opts);
        }
                die(_("Bad branch.%s.mergeoptions string: %s"), branch,
                    split_cmdline_strerror(argc));
        REALLOC_ARRAY(argv, argc + 2);
-       memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
+       MOVE_ARRAY(argv + 1, argv, argc + 1);
        argc++;
        argv[0] = "branch.*.mergeoptions";
        parse_options(argc, argv, NULL, builtin_merge_options,
        opts.verbose_update = 1;
        opts.trivial_merges_only = 1;
        opts.merge = 1;
-       trees[nr_trees] = parse_tree_indirect(common->hash);
+       trees[nr_trees] = parse_tree_indirect(common);
        if (!trees[nr_trees++])
                return -1;
-       trees[nr_trees] = parse_tree_indirect(head->hash);
+       trees[nr_trees] = parse_tree_indirect(head);
        if (!trees[nr_trees++])
                return -1;
-       trees[nr_trees] = parse_tree_indirect(one->hash);
+       trees[nr_trees] = parse_tree_indirect(one);
        if (!trees[nr_trees++])
                return -1;
        opts.fn = threeway_merge;
        if (!branch || is_null_oid(&head_oid))
                head_commit = NULL;
        else
-               head_commit = lookup_commit_or_die(head_oid.hash, "HEAD");
+               head_commit = lookup_commit_or_die(&head_oid, "HEAD");
 
        init_diff_ui_defaults();
        git_config(git_merge_config, NULL);
                        goto done;
                }
 
-               if (checkout_fast_forward(head_commit->object.oid.hash,
-                                         commit->object.oid.hash,
+               if (checkout_fast_forward(&head_commit->object.oid,
+                                         &commit->object.oid,
                                          overwrite_ignore)) {
                        ret = 1;
                        goto done;