Merge branch 'maint'

* maint:
  merge: do not setup worktree twice
  check-ref-format: update usage string

Conflicts:
	builtin-check-ref-format.c

builtin-check-ref-format.c

@@ -7,6 +7,10 @@
 #include "builtin.h"
 #include "strbuf.h"
 
+static const char builtin_check_ref_format_usage[] =
+"git check-ref-format [--print] <refname>\n"
+"   or: git check-ref-format --branch <branchname-shorthand>";
+
 /*
  * Replace each run of adjacent slashes in src with a single slash,
  * and write the result to dst.
@@ -49,6 +53,6 @@ int cmd_check_ref_format(int argc, const char **argv, const char *prefix)
 		exit(0);
 	}
 	if (argc != 2)
-		usage("git check-ref-format refname");
+		usage(builtin_check_ref_format_usage);
 	return !!check_ref_format(argv[1]);
 }

builtin-merge.c

@@ -846,7 +846,6 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 	const char *best_strategy = NULL, *wt_strategy = NULL;
 	struct commit_list **remotes = &remoteheads;
 
-	setup_work_tree();
 	if (file_exists(git_path("MERGE_HEAD")))
 		die("You have not concluded your merge. (MERGE_HEAD exists)");
 	if (read_cache_unmerged())