Merge branch 'jk/ref-paranoia' into jt/no-abuse-alternate-odb-for-submodules

* jk/ref-paranoia: (71 commits) refs: drop "broken" flag from for_each_fullref_in() ref-filter: drop broken-ref code entirely ref-filter: stop setting FILTER_REFS_INCLUDE_BROKEN repack, prune: drop GIT_REF_PARANOIA settings refs: turn on GIT_REF_PARANOIA by default refs: omit dangling symrefs when using GIT_REF_PARANOIA refs: add DO_FOR_EACH_OMIT_DANGLING_SYMREFS flag refs-internal.h: reorganize DO_FOR_EACH_* flag documentation refs-internal.h: move DO_FOR_EACH_* flags next to each other t5312: be more assertive about command failure t5312: test non-destructive repack t5312: create bogus ref as necessary t5312: drop "verbose" helper t5600: provide detached HEAD for corruption failures t5516: don't use HEAD ref for invalid ref-deletion tests t7900: clean up some more broken refs The eighth batch t0000: avoid masking git exit value through pipes tree-diff: fix leak when not HAVE_ALLOCA_H pack-revindex.h: correct the time complexity descriptions ...
2021-09-28 15:15:42 -07:00 · 2021-09-28 15:15:42 -07:00 · b6b210c5e1
--- a/Documentation/RelNotes/2.34.0.txt
+++ b/Documentation/RelNotes/2.34.0.txt
@ -48,6 +48,14 @@ UI, Workflows & Features
   entire directory outside the sparse cone to be removed, which is
   especially useful when the sparse patterns change.

+ * Taking advantage of the CGI interface, http-backend has been
+   updated to enable protocol v2 automatically when the other side
+   asks for it.
+
+ * The credential-cache helper has been adjusted to Windows.
+
+ * The error in "git help no-such-git-command" is handled better.
+

 Performance, Internal Implementation, Development Support etc.

@ -119,6 +127,9 @@ Performance, Internal Implementation, Development Support etc.
   ask the file descriptors open for packfiles to be closed immediately
   before spawning commands that may trigger auto-gc.

+ * An oddball OPTION_ARGUMENT feature has been removed from the
+   parse-options API.
+

 Fixes since v2.33
 -----------------
@ -245,6 +256,17 @@ Fixes since v2.33
   subsystem has been cleaned up.
   (merge 35cf94eaf6 rs/no-mode-to-open-when-appending later to maint).

+ * "git update-ref --stdin" failed to flush its output as needed,
+   which potentially led the conversation to a deadlock.
+   (merge 7c1200745b ps/update-ref-batch-flush later to maint).
+
+ * When "git am --abort" fails to abort correctly, it still exited
+   with exit status of 0, which has been corrected.
+   (merge c5ead19ea2 en/am-abort-fix later to maint).
+
+ * Correct nr and alloc members of strvec struct to be of type size_t.
+   (merge 8d133a4653 jk/strvec-typefix later to maint).
+
 * Other code cleanup, docfix, build fix, etc.
   (merge 1d9c8daef8 ab/bundle-doc later to maint).
   (merge 81483fe613 en/merge-strategy-docs later to maint).
@ -276,3 +298,8 @@ Fixes since v2.33
   (merge 92a5d1c9b4 jc/prefix-filename-allocates later to maint).
   (merge d9a65b6c0a rs/setup-use-xopen-and-xdup later to maint).
   (merge e8f55568de jk/t5562-racefix later to maint).
+   (merge 8f0f110156 rs/drop-core-compression-vars later to maint).
+   (merge b6d8887d3d ma/doc-git-version later to maint).
+   (merge 66c0c44df6 cb/plug-leaks-in-alloca-emu-users later to maint).
+   (merge afb32e8101 kz/revindex-comment-fix later to maint).
+   (merge ae578de926 po/git-config-doc-mentions-help-c later to maint).
--- a/Documentation/git-am.txt
+++ b/Documentation/git-am.txt
@ -178,6 +178,8 @@ default.   You can use `--no-utf8` to override this.

 --abort::
 	Restore the original branch and abort the patching operation.
+	Revert contents of files involved in the am operation to their
+	pre-am state.

 --quit::
 	Abort the patching operation but keep HEAD and the index
--- a/Documentation/git-config.txt
+++ b/Documentation/git-config.txt
@ -71,6 +71,9 @@ codes are:

 On success, the command returns the exit code 0.

+A list of all available configuration variables can be obtained using the
+`git help --config` command.
+
 [[OPTIONS]]
 OPTIONS
 -------
--- a/Documentation/git-http-backend.txt
+++ b/Documentation/git-http-backend.txt
@ -16,7 +16,9 @@ A simple CGI program to serve the contents of a Git repository to Git
 clients accessing the repository over http:// and https:// protocols.
 The program supports clients fetching using both the smart HTTP protocol
 and the backwards-compatible dumb HTTP protocol, as well as clients
-pushing using the smart HTTP protocol.
+pushing using the smart HTTP protocol. It also supports Git's
+more-efficient "v2" protocol if properly configured; see the
+discussion of `GIT_PROTOCOL` in the ENVIRONMENT section below.

 It verifies that the directory has the magic file
 "git-daemon-export-ok", and it will refuse to export any Git directory
@ -77,6 +79,18 @@ Apache 2.x::
 SetEnv GIT_PROJECT_ROOT /var/www/git
 SetEnv GIT_HTTP_EXPORT_ALL
 ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/
+
+# This is not strictly necessary using Apache and a modern version of
+# git-http-backend, as the webserver will pass along the header in the
+# environment as HTTP_GIT_PROTOCOL, and http-backend will copy that into
+# GIT_PROTOCOL. But you may need this line (or something similar if you
+# are using a different webserver), or if you want to support older Git
+# versions that did not do that copying.
+#
+# Having the webserver set up GIT_PROTOCOL is perfectly fine even with
+# modern versions (and will take precedence over HTTP_GIT_PROTOCOL,
+# which means it can be used to override the client's request).
+SetEnvIf Git-Protocol ".*" GIT_PROTOCOL=$0
 ----------------------------------------------------------------
 +
 To enable anonymous read access but authenticated write access,
@ -264,6 +278,16 @@ a repository with an extremely large number of refs.  The value can be
 specified with a unit (e.g., `100M` for 100 megabytes). The default is
 10 megabytes.

+Clients may probe for optional protocol capabilities (like the v2
+protocol) using the `Git-Protocol` HTTP header. In order to support
+these, the contents of that header must appear in the `GIT_PROTOCOL`
+environment variable. Most webservers will pass this header to the CGI
+via the `HTTP_GIT_PROTOCOL` variable, and `git-http-backend` will
+automatically copy that to `GIT_PROTOCOL`. However, some webservers may
+be more selective about which headers they'll pass, in which case they
+need to be configured explicitly (see the mention of `Git-Protocol` in
+the Apache config from the earlier EXAMPLES section).
+
 The backend process sets GIT_COMMITTER_NAME to '$REMOTE_USER' and
 GIT_COMMITTER_EMAIL to '$\{REMOTE_USER}@http.$\{REMOTE_ADDR\}',
 ensuring that any reflogs created by 'git-receive-pack' contain some
--- a/Documentation/git-upload-pack.txt
+++ b/Documentation/git-upload-pack.txt
@ -48,6 +48,14 @@ OPTIONS
 <directory>::
 	The repository to sync from.

+ENVIRONMENT
+-----------
+
+`GIT_PROTOCOL`::
+	Internal variable used for handshaking the wire protocol. Server
+	admins may need to configure some transports to allow this
+	variable to be passed. See the discussion in linkgit:git[1].
+
 SEE ALSO
 --------
 linkgit:gitnamespaces[7]
--- a/Documentation/git-version.txt
+++ b/Documentation/git-version.txt
@ -0,0 +1,28 @@
+git-version(1)
+==============
+
+NAME
+----
+git-version - Display version information about Git
+
+SYNOPSIS
+--------
+[verse]
+'git version' [--build-options]
+
+DESCRIPTION
+-----------
+With no options given, the version of 'git' is printed on the standard output.
+
+Note that `git --version` is identical to `git version` because the
+former is internally converted into the latter.
+
+OPTIONS
+-------
+--build-options::
+	Include additional information about how git was built for diagnostic
+	purposes.
+
+GIT
+---
+Part of the linkgit:git[1] suite
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@ -41,6 +41,10 @@ OPTIONS
 -------
 --version::
 	Prints the Git suite version that the 'git' program came from.
+
+This option is internaly converted to `git version ...` and accepts
+the same options as the linkgit:git-version[1] command. If `--help` is
+also given, it takes precedence over `--version`.

 --help::
 	Prints the synopsis and a list of the most commonly used
@ -863,15 +867,16 @@ for full details.
 	end user, to be recorded in the body of the reflog.

 `GIT_REF_PARANOIA`::
-	If set to `1`, include broken or badly named refs when iterating
-	over lists of refs. In a normal, non-corrupted repository, this
-	does nothing. However, enabling it may help git to detect and
-	abort some operations in the presence of broken refs. Git sets
-	this variable automatically when performing destructive
-	operations like linkgit:git-prune[1]. You should not need to set
-	it yourself unless you want to be paranoid about making sure
-	an operation has touched every ref (e.g., because you are
-	cloning a repository to make a backup).
+	If set to `0`, ignore broken or badly named refs when iterating
+	over lists of refs. Normally Git will try to include any such
+	refs, which may cause some operations to fail. This is usually
+	preferable, as potentially destructive operations (e.g.,
+	linkgit:git-prune[1]) are better off aborting rather than
+	ignoring broken refs (and thus considering the history they
+	point to as not worth saving). The default value is `1` (i.e.,
+	be paranoid about detecting and aborting all operations). You
+	should not normally need to set this to `0`, but it may be
+	useful when trying to salvage data from a corrupted repository.

 `GIT_ALLOW_PROTOCOL`::
 	If set to a colon-separated list of protocols, behave as if
@ -894,6 +899,21 @@ for full details.
 	Contains a colon ':' separated list of keys with optional values
 	'key[=value]'.  Presence of unknown keys and values must be
 	ignored.
+
+Note that servers may need to be configured to allow this variable to
+pass over some transports. It will be propagated automatically when
+accessing local repositories (i.e., `file://` or a filesystem path), as
+well as over the `git://` protocol. For git-over-http, it should work
+automatically in most configurations, but see the discussion in
+linkgit:git-http-backend[1]. For git-over-ssh, the ssh server may need
+to be configured to allow clients to pass this variable (e.g., by using
+`AcceptEnv GIT_PROTOCOL` with OpenSSH).
+
+This configuration is optional. If the variable is not propagated, then
+clients will fall back to the original "v0" protocol (but may miss out
+on some performance improvements or features). This variable currently
+only affects clones and fetches; it is not yet used for pushes (but may
+be in the future).

 `GIT_OPTIONAL_LOCKS`::
 	If set to `0`, Git will complete any requested operation without
--- a/Documentation/technical/api-parse-options.txt
+++ b/Documentation/technical/api-parse-options.txt
@ -198,11 +198,6 @@ There are some macros to easily define options:
 	The filename will be prefixed by passing the filename along with
 	the prefix argument of `parse_options()` to `prefix_filename()`.

-`OPT_ARGUMENT(long, &int_var, description)`::
-	Introduce a long-option argument that will be kept in `argv[]`.
-	If this option was seen, `int_var` will be set to one (except
-	if a `NULL` pointer was passed).
-
 `OPT_NUMBER_CALLBACK(&var, description, func_ptr)`::
 	Recognize numerical options like -123 and feed the integer as
 	if it was an argument to the function given by `func_ptr`.
--- a/Documentation/technical/protocol-v2.txt
+++ b/Documentation/technical/protocol-v2.txt
@ -42,7 +42,8 @@ Initial Client Request
 In general a client can request to speak protocol v2 by sending
 `version=2` through the respective side-channel for the transport being
 used which inevitably sets `GIT_PROTOCOL`.  More information can be
-found in `pack-protocol.txt` and `http-protocol.txt`.  In all cases the
+found in `pack-protocol.txt` and `http-protocol.txt`, as well as the
+`GIT_PROTOCOL` definition in `git.txt`. In all cases the
 response from the server is the capability advertisement.

 Git Transport
@ -58,6 +59,8 @@ SSH and File Transport

 When using either the ssh:// or file:// transport, the GIT_PROTOCOL
 environment variable must be set explicitly to include "version=2".
+The server may need to be configured to allow this environment variable
+to pass.

 HTTP Transport
 ~~~~~~~~~~~~~~
@ -84,6 +87,9 @@ Subsequent requests are then made directly to the service
 Uses the `--http-backend-info-refs` option to
 linkgit:git-upload-pack[1].

+The server may need to be configured to pass this header's contents via
+the `GIT_PROTOCOL` variable. See the discussion in `git-http-backend.txt`.
+
 Capability Advertisement
 ------------------------

--- a/15
+++ b/15
@ -138,12 +138,15 @@ Issues of note:
 	  BLK_SHA1.  Also included is a version optimized for PowerPC
 	  (PPC_SHA1).

-	- "libcurl" library is used by git-http-fetch, git-fetch, and, if
-	  the curl version >= 7.34.0, for git-imap-send.  You might also
-	  want the "curl" executable for debugging purposes. If you do not
-	  use http:// or https:// repositories, and do not want to put
-	  patches into an IMAP mailbox, you do not have to have them
-	  (use NO_CURL).
+	- "libcurl" library is used for fetching and pushing
+	  repositories over http:// or https://, as well as by
+	  git-imap-send if the curl version is >= 7.34.0. If you do
+	  not need that functionality, use NO_CURL to build without
+	  it.
+
+	  Git requires version "7.19.4" or later of "libcurl" to build
+	  without NO_CURL. This version requirement may be bumped in
+	  the future.

 	- "expat" library; git-http-push uses it for remote lock
 	  management over DAV.  Similar to "curl" above, this is optional
--- a/11
+++ b/11
@ -1421,15 +1421,8 @@ else
 	REMOTE_CURL_NAMES = $(REMOTE_CURL_PRIMARY) $(REMOTE_CURL_ALIASES)
 	PROGRAM_OBJS += http-fetch.o
 	PROGRAMS += $(REMOTE_CURL_NAMES)
-	curl_check := $(shell (echo 070908; $(CURL_CONFIG) --vernum | sed -e '/^70[BC]/s/^/0/') 2>/dev/null | sort -r | sed -ne 2p)
-	ifeq "$(curl_check)" "070908"
-		ifndef NO_EXPAT
-			PROGRAM_OBJS += http-push.o
-		else
-			EXCLUDED_PROGRAMS += git-http-push
-		endif
-	else
-		EXCLUDED_PROGRAMS += git-http-push
+	ifndef NO_EXPAT
+		PROGRAM_OBJS += http-push.o
 	endif
 	curl_check := $(shell (echo 072200; $(CURL_CONFIG) --vernum | sed -e '/^70[BC]/s/^/0/') 2>/dev/null | sort -r | sed -ne 2p)
 	ifeq "$(curl_check)" "072200"
--- a/builtin/am.c
+++ b/builtin/am.c
@ -2105,7 +2105,8 @@ static void am_abort(struct am_state *state)
 	if (!has_orig_head)
 		oidcpy(&orig_head, the_hash_algo->empty_tree);

-	clean_index(&curr_head, &orig_head);
+	if (clean_index(&curr_head, &orig_head))
+		die(_("failed to clean index"));

 	if (has_orig_head)
 		update_ref("am --abort", "HEAD", &orig_head,
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@ -18,10 +18,10 @@ static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
 static GIT_PATH_FUNC(git_path_head_name, "head-name")
 static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
 static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
+static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")

 static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-reset [<commit>]"),
-	N_("git bisect--helper --bisect-next-check <good_term> <bad_term> [<term>]"),
 	N_("git bisect--helper --bisect-terms [--term-good | --term-old | --term-bad | --term-new]"),
 	N_("git bisect--helper --bisect-start [--term-{new,bad}=<term> --term-{old,good}=<term>]"
 					    " [--no-checkout] [--first-parent] [<bad> [<good>...]] [--] [<paths>...]"),
@ -30,6 +30,8 @@ static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-state (good|old) [<rev>...]"),
 	N_("git bisect--helper --bisect-replay <filename>"),
 	N_("git bisect--helper --bisect-skip [(<rev>|<range>)...]"),
+	N_("git bisect--helper --bisect-visualize"),
+	N_("git bisect--helper --bisect-run <cmd>..."),
 	NULL
 };

@ -143,6 +145,19 @@ static int append_to_file(const char *path, const char *format, ...)
 	return res;
 }

+static int print_file_to_stdout(const char *path)
+{
+	int fd = open(path, O_RDONLY);
+	int ret = 0;
+
+	if (fd < 0)
+		return error_errno(_("cannot open file '%s' for reading"), path);
+	if (copy_fd(fd, 1) < 0)
+		ret = error_errno(_("failed to read '%s'"), path);
+	close(fd);
+	return ret;
+}
+
 static int check_term_format(const char *term, const char *orig_term)
 {
 	int res;
@ -1036,6 +1051,125 @@ static enum bisect_error bisect_skip(struct bisect_terms *terms, const char **ar
 	return res;
 }

+static int bisect_visualize(struct bisect_terms *terms, const char **argv, int argc)
+{
+	struct strvec args = STRVEC_INIT;
+	int flags = RUN_COMMAND_NO_STDIN, res = 0;
+	struct strbuf sb = STRBUF_INIT;
+
+	if (bisect_next_check(terms, NULL) != 0)
+		return BISECT_FAILED;
+
+	if (!argc) {
+		if ((getenv("DISPLAY") || getenv("SESSIONNAME") || getenv("MSYSTEM") ||
+		     getenv("SECURITYSESSIONID")) && exists_in_PATH("gitk")) {
+			strvec_push(&args, "gitk");
+		} else {
+			strvec_push(&args, "log");
+			flags |= RUN_GIT_CMD;
+		}
+	} else {
+		if (argv[0][0] == '-') {
+			strvec_push(&args, "log");
+			flags |= RUN_GIT_CMD;
+		} else if (strcmp(argv[0], "tig") && !starts_with(argv[0], "git"))
+			flags |= RUN_GIT_CMD;
+
+		strvec_pushv(&args, argv);
+	}
+
+	strvec_pushl(&args, "--bisect", "--", NULL);
+
+	strbuf_read_file(&sb, git_path_bisect_names(), 0);
+	sq_dequote_to_strvec(sb.buf, &args);
+	strbuf_release(&sb);
+
+	res = run_command_v_opt(args.v, flags);
+	strvec_clear(&args);
+	return res;
+}
+
+static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
+{
+	int res = BISECT_OK;
+	struct strbuf command = STRBUF_INIT;
+	struct strvec args = STRVEC_INIT;
+	struct strvec run_args = STRVEC_INIT;
+	const char *new_state;
+	int temporary_stdout_fd, saved_stdout;
+
+	if (bisect_next_check(terms, NULL))
+		return BISECT_FAILED;
+
+	if (argc)
+		sq_quote_argv(&command, argv);
+	else {
+		error(_("bisect run failed: no command provided."));
+		return BISECT_FAILED;
+	}
+
+	strvec_push(&run_args, command.buf);
+
+	while (1) {
+		strvec_clear(&args);
+
+		printf(_("running %s\n"), command.buf);
+		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
+
+		if (res < 0 || 128 <= res) {
+			error(_("bisect run failed: exit code %d from"
+				" '%s' is < 0 or >= 128"), res, command.buf);
+			strbuf_release(&command);
+			return res;
+		}
+
+		if (res == 125)
+			new_state = "skip";
+		else if (!res)
+			new_state = terms->term_good;
+		else
+			new_state = terms->term_bad;
+
+		temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
+
+		if (temporary_stdout_fd < 0)
+			return error_errno(_("cannot open file '%s' for writing"), git_path_bisect_run());
+
+		fflush(stdout);
+		saved_stdout = dup(1);
+		dup2(temporary_stdout_fd, 1);
+
+		res = bisect_state(terms, &new_state, 1);
+
+		fflush(stdout);
+		dup2(saved_stdout, 1);
+		close(saved_stdout);
+		close(temporary_stdout_fd);
+
+		print_file_to_stdout(git_path_bisect_run());
+
+		if (res == BISECT_ONLY_SKIPPED_LEFT)
+			error(_("bisect run cannot continue any more"));
+		else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
+			printf(_("bisect run success"));
+			res = BISECT_OK;
+		} else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
+			printf(_("bisect found first bad commit"));
+			res = BISECT_OK;
+		} else if (res) {
+			error(_("bisect run failed:'git bisect--helper --bisect-state"
+			" %s' exited with error code %d"), args.v[0], res);
+		} else {
+			continue;
+		}
+
+		strbuf_release(&command);
+		strvec_clear(&args);
+		strvec_clear(&run_args);
+		return res;
+	}
+}
+
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 {
 	enum {
@ -1048,7 +1182,9 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		BISECT_STATE,
 		BISECT_LOG,
 		BISECT_REPLAY,
-		BISECT_SKIP
+		BISECT_SKIP,
+		BISECT_VISUALIZE,
+		BISECT_RUN,
 	} cmdmode = 0;
 	int res = 0, nolog = 0;
 	struct option options[] = {
@ -1070,6 +1206,10 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			 N_("replay the bisection process from the given file"), BISECT_REPLAY),
 		OPT_CMDMODE(0, "bisect-skip", &cmdmode,
 			 N_("skip some commits for checkout"), BISECT_SKIP),
+		OPT_CMDMODE(0, "bisect-visualize", &cmdmode,
+			 N_("visualize the bisection"), BISECT_VISUALIZE),
+		OPT_CMDMODE(0, "bisect-run", &cmdmode,
+			 N_("use <cmd>... to automatically bisect."), BISECT_RUN),
 		OPT_BOOL(0, "no-log", &nolog,
 			 N_("no log for BISECT_WRITE")),
 		OPT_END()
@ -1089,12 +1229,6 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			return error(_("--bisect-reset requires either no argument or a commit"));
 		res = bisect_reset(argc ? argv[0] : NULL);
 		break;
-	case BISECT_NEXT_CHECK:
-		if (argc != 2 && argc != 3)
-			return error(_("--bisect-next-check requires 2 or 3 arguments"));
-		set_terms(&terms, argv[1], argv[0]);
-		res = bisect_next_check(&terms, argc == 3 ? argv[2] : NULL);
-		break;
 	case BISECT_TERMS:
 		if (argc > 1)
 			return error(_("--bisect-terms requires 0 or 1 argument"));
@ -1131,6 +1265,16 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		get_terms(&terms);
 		res = bisect_skip(&terms, argv, argc);
 		break;
+	case BISECT_VISUALIZE:
+		get_terms(&terms);
+		res = bisect_visualize(&terms, argv, argc);
+		break;
+	case BISECT_RUN:
+		if (!argc)
+			return error(_("bisect run failed: no command provided."));
+		get_terms(&terms);
+		res = bisect_run(&terms, argv, argc);
+		break;
 	default:
 		BUG("unknown subcommand %d", cmdmode);
 	}
--- a/builtin/branch.c
+++ b/builtin/branch.c
@ -427,7 +427,7 @@ static void print_ref_list(struct ref_filter *filter, struct ref_sorting *sortin

 	memset(&array, 0, sizeof(array));

-	filter_refs(&array, filter, filter->kind | FILTER_REFS_INCLUDE_BROKEN);
+	filter_refs(&array, filter, filter->kind);

 	if (filter->verbose)
 		maxwidth = calc_maxwidth(&array, strlen(remote_prefix));
--- a/builtin/credential-cache.c
+++ b/builtin/credential-cache.c
@ -11,6 +11,32 @@
 #define FLAG_SPAWN 0x1
 #define FLAG_RELAY 0x2

+#ifdef GIT_WINDOWS_NATIVE
+
+static int connection_closed(int error)
+{
+	return (error == EINVAL);
+}
+
+static int connection_fatally_broken(int error)
+{
+	return (error != ENOENT) && (error != ENETDOWN);
+}
+
+#else
+
+static int connection_closed(int error)
+{
+	return (error == ECONNRESET);
+}
+
+static int connection_fatally_broken(int error)
+{
+	return (error != ENOENT) && (error != ECONNREFUSED);
+}
+
+#endif
+
 static int send_request(const char *socket, const struct strbuf *out)
 {
 	int got_data = 0;
@ -28,7 +54,7 @@ static int send_request(const char *socket, const struct strbuf *out)
 		int r;

 		r = read_in_full(fd, in, sizeof(in));
-		if (r == 0 || (r < 0 && errno == ECONNRESET))
+		if (r == 0 || (r < 0 && connection_closed(errno)))
 			break;
 		if (r < 0)
 			die_errno("read error from cache daemon");
@ -75,7 +101,7 @@ static void do_cache(const char *socket, const char *action, int timeout,
 	}

 	if (send_request(socket, &buf) < 0) {
-		if (errno != ENOENT && errno != ECONNREFUSED)
+		if (connection_fatally_broken(errno))
 			die_errno("unable to connect to cache daemon");
 		if (flags & FLAG_SPAWN) {
 			spawn_daemon(socket);
--- a/builtin/difftool.c
+++ b/builtin/difftool.c
@ -331,7 +331,7 @@ static int checkout_path(unsigned mode, struct object_id *oid,
 }

 static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
-			int argc, const char **argv)
+			struct child_process *child)
 {
 	char tmpdir[PATH_MAX];
 	struct strbuf info = STRBUF_INIT, lpath = STRBUF_INIT;
@ -352,7 +352,6 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 	struct index_state wtindex;
 	struct checkout lstate, rstate;
 	int rc, flags = RUN_GIT_CMD, err = 0;
-	struct child_process child = CHILD_PROCESS_INIT;
 	const char *helper_argv[] = { "difftool--helper", NULL, NULL, NULL };
 	struct hashmap wt_modified, tmp_modified;
 	int indices_loaded = 0;
@ -387,19 +386,15 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 	rdir_len = rdir.len;
 	wtdir_len = wtdir.len;

-	child.no_stdin = 1;
-	child.git_cmd = 1;
-	child.use_shell = 0;
-	child.clean_on_exit = 1;
-	child.dir = prefix;
-	child.out = -1;
-	strvec_pushl(&child.args, "diff", "--raw", "--no-abbrev", "-z",
-		     NULL);
-	for (i = 0; i < argc; i++)
-		strvec_push(&child.args, argv[i]);
-	if (start_command(&child))
+	child->no_stdin = 1;
+	child->git_cmd = 1;
+	child->use_shell = 0;
+	child->clean_on_exit = 1;
+	child->dir = prefix;
+	child->out = -1;
+	if (start_command(child))
 		die("could not obtain raw diff");
-	fp = xfdopen(child.out, "r");
+	fp = xfdopen(child->out, "r");

 	/* Build index info for left and right sides of the diff */
 	i = 0;
@ -525,7 +520,7 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,

 	fclose(fp);
 	fp = NULL;
-	if (finish_command(&child)) {
+	if (finish_command(child)) {
 		ret = error("error occurred running diff --raw");
 		goto finish;
 	}
@ -668,25 +663,23 @@ finish:
 }

 static int run_file_diff(int prompt, const char *prefix,
-			 int argc, const char **argv)
+			 struct child_process *child)
 {
-	struct strvec args = STRVEC_INIT;
 	const char *env[] = {
 		"GIT_PAGER=", "GIT_EXTERNAL_DIFF=git-difftool--helper", NULL,
 		NULL
 	};
-	int i;

 	if (prompt > 0)
 		env[2] = "GIT_DIFFTOOL_PROMPT=true";
 	else if (!prompt)
 		env[2] = "GIT_DIFFTOOL_NO_PROMPT=true";

+	child->git_cmd = 1;
+	child->dir = prefix;
+	strvec_pushv(&child->env_array, env);

-	strvec_push(&args, "diff");
-	for (i = 0; i < argc; i++)
-		strvec_push(&args, argv[i]);
-	return run_command_v_opt_cd_env(args.v, RUN_GIT_CMD, prefix, env);
+	return run_command(child);
 }

 int cmd_difftool(int argc, const char **argv, const char *prefix)
@ -716,9 +709,10 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
 			    "tool returns a non - zero exit code")),
 		OPT_STRING('x', "extcmd", &extcmd, N_("command"),
 			   N_("specify a custom command for viewing diffs")),
-		OPT_ARGUMENT("no-index", &no_index, N_("passed to `diff`")),
+		OPT_BOOL(0, "no-index", &no_index, N_("passed to `diff`")),
 		OPT_END()
 	};
+	struct child_process child = CHILD_PROCESS_INIT;

 	git_config(difftool_config, NULL);
 	symlinks = has_symlinks;
@ -768,7 +762,14 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
 	 * will invoke a separate instance of 'git-difftool--helper' for
 	 * each file that changed.
 	 */
+	strvec_push(&child.args, "diff");
+	if (no_index)
+		strvec_push(&child.args, "--no-index");
 	if (dir_diff)
-		return run_dir_diff(extcmd, symlinks, prefix, argc, argv);
-	return run_file_diff(prompt, prefix, argc, argv);
+		strvec_pushl(&child.args, "--raw", "--no-abbrev", "-z", NULL);
+	strvec_pushv(&child.args, argv);
+
+	if (dir_diff)
+		return run_dir_diff(extcmd, symlinks, prefix, &child);
+	return run_file_diff(prompt, prefix, &child);
 }
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c
@ -77,7 +77,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)

 	filter.name_patterns = argv;
 	filter.match_as_path = 1;
-	filter_refs(&array, &filter, FILTER_REFS_ALL | FILTER_REFS_INCLUDE_BROKEN);
+	filter_refs(&array, &filter, FILTER_REFS_ALL);
 	ref_array_sort(sorting, &array);

 	if (!maxcount || array.nr < maxcount)
--- a/builtin/gc.c
+++ b/builtin/gc.c
@ -1681,9 +1681,7 @@ static int launchctl_remove_plists(void)

 static int launchctl_list_contains_plist(const char *name, const char *cmd)
 {
-	int result;
 	struct child_process child = CHILD_PROCESS_INIT;
-	char *uid = launchctl_get_uid();

 	strvec_split(&child.args, cmd);
 	strvec_pushl(&child.args, "list", name, NULL);
@ -1694,12 +1692,8 @@ static int launchctl_list_contains_plist(const char *name, const char *cmd)
 	if (start_command(&child))
 		die(_("failed to start launchctl"));

-	result = finish_command(&child);
-
-	free(uid);
-
 	/* Returns failure if 'name' doesn't exist. */
-	return !result;
+	return !finish_command(&child);
 }

 static int launchctl_schedule_plist(const char *exec_path, enum schedule_priority schedule)
--- a/builtin/help.c
+++ b/builtin/help.c
@ -467,11 +467,14 @@ static void get_html_page_path(struct strbuf *page_path, const char *page)
 	if (!html_path)
 		html_path = to_free = system_path(GIT_HTML_PATH);

-	/* Check that we have a git documentation directory. */
+	/*
+	 * Check that the page we're looking for exists.
+	 */
 	if (!strstr(html_path, "://")) {
-		if (stat(mkpath("%s/git.html", html_path), &st)
+		if (stat(mkpath("%s/%s.html", html_path, page), &st)
 		    || !S_ISREG(st.st_mode))
-			die("'%s': not a documentation directory.", html_path);
+			die("'%s/%s.html': documentation file not found.",
+				html_path, page);
 	}

 	strbuf_init(page_path, 0);
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@ -188,9 +188,7 @@ static void init_thread(void)
 	pthread_key_create(&key, NULL);
 	CALLOC_ARRAY(thread_data, nr_threads);
 	for (i = 0; i < nr_threads; i++) {
-		thread_data[i].pack_fd = open(curr_pack, O_RDONLY);
-		if (thread_data[i].pack_fd == -1)
-			die_errno(_("unable to open %s"), curr_pack);
+		thread_data[i].pack_fd = xopen(curr_pack, O_RDONLY);
 	}

 	threads_active = 1;
--- a/builtin/prune.c
+++ b/builtin/prune.c
@ -143,7 +143,6 @@ int cmd_prune(int argc, const char **argv, const char *prefix)
 	expire = TIME_MAX;
 	save_commit_buffer = 0;
 	read_replace_refs = 0;
-	ref_paranoia = 1;
 	repo_init_revisions(the_repository, &revs, prefix);

 	argc = parse_options(argc, argv, prefix, options, prune_usage, 0);
--- a/builtin/repack.c
+++ b/builtin/repack.c
@ -586,15 +586,12 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 				strvec_pushf(&cmd.args,
 					     "--unpack-unreachable=%s",
 					     unpack_unreachable);
-				strvec_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 			} else if (pack_everything & LOOSEN_UNREACHABLE) {
 				strvec_push(&cmd.args,
 					    "--unpack-unreachable");
 			} else if (keep_unreachable) {
 				strvec_push(&cmd.args, "--keep-unreachable");
 				strvec_push(&cmd.args, "--pack-loose-unreachable");
-			} else {
-				strvec_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 			}
 		}
 	} else if (geometry) {
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@ -863,8 +863,8 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 				continue;
 			}
 			if (!strcmp(arg, "--bisect")) {
-				for_each_fullref_in("refs/bisect/bad", show_reference, NULL, 0);
-				for_each_fullref_in("refs/bisect/good", anti_reference, NULL, 0);
+				for_each_fullref_in("refs/bisect/bad", show_reference, NULL);
+				for_each_fullref_in("refs/bisect/good", anti_reference, NULL);
 				continue;
 			}
 			if (opt_with_value(arg, "--branches", &arg)) {
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@ -1668,18 +1668,24 @@ static int add_possible_reference_from_superproject(
 	 * standard layout with .git/(modules/<name>)+/objects
 	 */
 	if (strip_suffix(odb->path, "/objects", &len)) {
+		struct repository alternate;
 		char *sm_alternate;
 		struct strbuf sb = STRBUF_INIT;
 		struct strbuf err = STRBUF_INIT;
 		strbuf_add(&sb, odb->path, len);

+		repo_init(&alternate, sb.buf, NULL);
+
 		/*
 		 * We need to end the new path with '/' to mark it as a dir,
 		 * otherwise a submodule name containing '/' will be broken
 		 * as the last part of a missing submodule reference would
 		 * be taken as a file name.
 		 */
-		strbuf_addf(&sb, "/modules/%s/", sas->submodule_name);
+		strbuf_reset(&sb);
+		submodule_name_to_gitdir(&sb, &alternate, sas->submodule_name);
+		strbuf_addch(&sb, '/');
+		repo_clear(&alternate);

 		sm_alternate = compute_alternate_path(sb.buf, &err);
 		if (sm_alternate) {
@ -1749,7 +1755,7 @@ static int clone_submodule(struct module_clone_data *clone_data)
 	struct strbuf sb = STRBUF_INIT;
 	struct child_process cp = CHILD_PROCESS_INIT;

-	strbuf_addf(&sb, "%s/modules/%s", get_git_dir(), clone_data->name);
+	submodule_name_to_gitdir(&sb, the_repository, clone_data->name);
 	sm_gitdir = absolute_pathdup(sb.buf);
 	strbuf_reset(&sb);

--- a/builtin/update-ref.c
+++ b/builtin/update-ref.c
@ -302,6 +302,12 @@ static void parse_cmd_verify(struct ref_transaction *transaction,
 	strbuf_release(&err);
 }

+static void report_ok(const char *command)
+{
+	fprintf(stdout, "%s: ok\n", command);
+	fflush(stdout);
+}
+
 static void parse_cmd_option(struct ref_transaction *transaction,
 			     const char *next, const char *end)
 {
@ -317,7 +323,7 @@ static void parse_cmd_start(struct ref_transaction *transaction,
 {
 	if (*next != line_termination)
 		die("start: extra input: %s", next);
-	puts("start: ok");
+	report_ok("start");
 }

 static void parse_cmd_prepare(struct ref_transaction *transaction,
@ -328,7 +334,7 @@ static void parse_cmd_prepare(struct ref_transaction *transaction,
 		die("prepare: extra input: %s", next);
 	if (ref_transaction_prepare(transaction, &error))
 		die("prepare: %s", error.buf);
-	puts("prepare: ok");
+	report_ok("prepare");
 }

 static void parse_cmd_abort(struct ref_transaction *transaction,
@ -339,7 +345,7 @@ static void parse_cmd_abort(struct ref_transaction *transaction,
 		die("abort: extra input: %s", next);
 	if (ref_transaction_abort(transaction, &error))
 		die("abort: %s", error.buf);
-	puts("abort: ok");
+	report_ok("abort");
 }

 static void parse_cmd_commit(struct ref_transaction *transaction,
@ -350,7 +356,7 @@ static void parse_cmd_commit(struct ref_transaction *transaction,
 		die("commit: extra input: %s", next);
 	if (ref_transaction_commit(transaction, &error))
 		die("commit: %s", error.buf);
-	puts("commit: ok");
+	report_ok("commit");
 	ref_transaction_free(transaction);
 }

--- a/cache.h
+++ b/cache.h
@ -958,7 +958,6 @@ extern char *apply_default_ignorewhitespace;
 extern const char *git_attributes_file;
 extern const char *git_hooks_path;
 extern int zlib_compression_level;
-extern int core_compression_level;
 extern int pack_compression_level;
 extern size_t packed_git_window_size;
 extern size_t packed_git_limit;
@ -995,14 +994,6 @@ extern const char *core_fsmonitor;
 extern int core_apply_sparse_checkout;
 extern int core_sparse_checkout_cone;

-/*
- * Include broken refs in all ref iterations, which will
- * generally choke dangerous operations rather than letting
- * them silently proceed without taking the broken ref into
- * account.
- */
-extern int ref_paranoia;
-
 /*
 * Returns the boolean value of $GIT_OPTIONAL_LOCKS (or the default value).
 */
--- a/config.c
+++ b/config.c
@ -76,7 +76,6 @@ static struct key_value_info *current_config_kvi;
 */
 static enum config_scope current_parsing_scope;

-static int core_compression_seen;
 static int pack_compression_seen;
 static int zlib_compression_seen;

@ -1400,8 +1399,6 @@ static int git_default_core_config(const char *var, const char *value, void *cb)
 			level = Z_DEFAULT_COMPRESSION;
 		else if (level < 0 || level > Z_BEST_COMPRESSION)
 			die(_("bad zlib compression level %d"), level);
-		core_compression_level = level;
-		core_compression_seen = 1;
 		if (!zlib_compression_seen)
 			zlib_compression_level = level;
 		if (!pack_compression_seen)
--- a/contrib/coccinelle/xopen.cocci
+++ b/contrib/coccinelle/xopen.cocci
@ -2,15 +2,18 @@
 identifier fd;
 identifier die_fn =~ "^(die|die_errno)$";
@@
-(
-  fd =
- open
-+ xopen
-  (...);
-|
  int fd =
 - open
 + xopen
  (...);
-)
+- if ( \( fd < 0 \| fd == -1 \) ) { die_fn(...); }
+
+@@
+expression fd;
+identifier die_fn =~ "^(die|die_errno)$";
+@@
+  fd =
+- open
+ xopen
+  (...);
 - if ( \( fd < 0 \| fd == -1 \) ) { die_fn(...); }
--- a/dir.c
+++ b/dir.c
@ -3799,7 +3799,7 @@ static void connect_wt_gitdir_in_nested(const char *sub_worktree,
 		strbuf_reset(&sub_wt);
 		strbuf_reset(&sub_gd);
 		strbuf_addf(&sub_wt, "%s/%s", sub_worktree, sub->path);
-		strbuf_addf(&sub_gd, "%s/modules/%s", sub_gitdir, sub->name);
+		submodule_name_to_gitdir(&sub_gd, &subrepo, sub->name);

 		connect_work_tree_and_git_dir(sub_wt.buf, sub_gd.buf, 1);
 	}
--- a/environment.c
+++ b/environment.c
@ -31,7 +31,6 @@ int prefer_symlink_refs;
 int is_bare_repository_cfg = -1; /* unspecified */
 int warn_ambiguous_refs = 1;
 int warn_on_object_refname_ambiguity = 1;
-int ref_paranoia = -1;
 int repository_format_precious_objects;
 int repository_format_worktree_config;
 const char *git_commit_encoding;
@ -41,7 +40,6 @@ char *apply_default_ignorewhitespace;
 const char *git_attributes_file;
 const char *git_hooks_path;
 int zlib_compression_level = Z_BEST_SPEED;
-int core_compression_level;
 int pack_compression_level = Z_DEFAULT_COMPRESSION;
 int fsync_object_files;
 size_t packed_git_window_size = DEFAULT_PACKED_GIT_WINDOW_SIZE;
--- a/git-bisect.sh
+++ b/git-bisect.sh
@ -34,94 +34,9 @@ Please use "git help bisect" to get the full man page.'
 OPTIONS_SPEC=
 . git-sh-setup

-_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
-_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 TERM_BAD=bad
 TERM_GOOD=good

-bisect_visualize() {
-	git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit
-
-	if test $# = 0
-	then
-		if test -n "${DISPLAY+set}${SESSIONNAME+set}${MSYSTEM+set}${SECURITYSESSIONID+set}" &&
-			type gitk >/dev/null 2>&1
-		then
-			set gitk
-		else
-			set git log
-		fi
-	else
-		case "$1" in
-		git*|tig) ;;
-		-*)	set git log "$@" ;;
-		*)	set git "$@" ;;
-		esac
-	fi
-
-	eval '"$@"' --bisect -- $(cat "$GIT_DIR/BISECT_NAMES")
-}
-
-bisect_run () {
-	git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit
-
-	test -n "$*" || die "$(gettext "bisect run failed: no command provided.")"
-
-	while true
-	do
-		command="$@"
-		eval_gettextln "running \$command"
-		"$@"
-		res=$?
-
-		# Check for really bad run error.
-		if [ $res -lt 0 -o $res -ge 128 ]
-		then
-			eval_gettextln "bisect run failed:
-exit code \$res from '\$command' is < 0 or >= 128" >&2
-			exit $res
-		fi
-
-		# Find current state depending on run success or failure.
-		# A special exit code of 125 means cannot test.
-		if [ $res -eq 125 ]
-		then
-			state='skip'
-		elif [ $res -gt 0 ]
-		then
-			state="$TERM_BAD"
-		else
-			state="$TERM_GOOD"
-		fi
-
-		git bisect--helper --bisect-state $state >"$GIT_DIR/BISECT_RUN"
-		res=$?
-
-		cat "$GIT_DIR/BISECT_RUN"
-
-		if sane_grep "first $TERM_BAD commit could be any of" "$GIT_DIR/BISECT_RUN" \
-			>/dev/null
-		then
-			gettextln "bisect run cannot continue any more" >&2
-			exit $res
-		fi
-
-		if [ $res -ne 0 ]
-		then
-			eval_gettextln "bisect run failed:
-'bisect-state \$state' exited with error code \$res" >&2
-			exit $res
-		fi
-
-		if sane_grep "is the first $TERM_BAD commit" "$GIT_DIR/BISECT_RUN" >/dev/null
-		then
-			gettextln "bisect run success"
-			exit 0;
-		fi
-
-	done
-}
-
 get_terms () {
 	if test -s "$GIT_DIR/BISECT_TERMS"
 	then
@ -152,7 +67,7 @@ case "$#" in
 		# Not sure we want "next" at the UI level anymore.
 		git bisect--helper --bisect-next "$@" || exit ;;
 	visualize|view)
-		bisect_visualize "$@" ;;
+		git bisect--helper --bisect-visualize "$@" || exit;;
 	reset)
 		git bisect--helper --bisect-reset "$@" ;;
 	replay)
@ -160,7 +75,7 @@ case "$#" in
 	log)
 		git bisect--helper --bisect-log || exit ;;
 	run)
-		bisect_run "$@" ;;
+		git bisect--helper --bisect-run "$@" || exit;;
 	terms)
 		git bisect--helper --bisect-terms "$@" || exit;;
 	*)
--- a/git-compat-util.h
+++ b/git-compat-util.h
@ -160,6 +160,9 @@
 # endif
 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 #include <winsock2.h>
+#ifndef NO_UNIX_SOCKETS
+#include <afunix.h>
+#endif
 #include <windows.h>
 #define GIT_WINDOWS_NATIVE
 #endif
--- a/git-curl-compat.h
+++ b/git-curl-compat.h
@ -0,0 +1,128 @@
+#ifndef GIT_CURL_COMPAT_H
+#define GIT_CURL_COMPAT_H
+#include <curl/curl.h>
+
+/**
+ * This header centralizes the declaration of our libcurl dependencies
+ * to make it easy to discover the oldest versions we support, and to
+ * inform decisions about removing support for older libcurl in the
+ * future.
+ *
+ * The oldest supported version of curl is documented in the "INSTALL"
+ * document.
+ *
+ * The source of truth for what versions have which symbols is
+ * https://github.com/curl/curl/blob/master/docs/libcurl/symbols-in-versions;
+ * the release dates are taken from curl.git (at
+ * https://github.com/curl/curl/).
+ *
+ * For each X symbol we need from curl we define our own
+ * GIT_CURL_HAVE_X. If multiple similar symbols with the same prefix
+ * were defined in the same version we pick one and check for that name.
+ *
+ * We may also define a missing CURL_* symbol to its known value, if
+ * doing so is sufficient to add support for it to older versions that
+ * don't have it.
+ *
+ * Keep any symbols in date order of when their support was
+ * introduced, oldest first, in the official version of cURL library.
+ */
+
+/**
+ * CURL_SOCKOPT_OK was added in 7.21.5, released in April 2011.
+ */
+#if LIBCURL_VERSION_NUM < 0x071505
+#define CURL_SOCKOPT_OK 0
+#endif
+
+/**
+ * CURLOPT_TCP_KEEPALIVE was added in 7.25.0, released in March 2012.
+ */
+#if LIBCURL_VERSION_NUM >= 0x071900
+#define GITCURL_HAVE_CURLOPT_TCP_KEEPALIVE 1
+#endif
+
+
+/**
+ * CURLOPT_LOGIN_OPTIONS was added in 7.34.0, released in December
+ * 2013.
+ *
+ * If we start requiring 7.34.0 we might also be able to remove the
+ * code conditional on USE_CURL_FOR_IMAP_SEND in imap-send.c, see
+ * 1e16b255b95 (git-imap-send: use libcurl for implementation,
+ * 2014-11-09) and the check it added for "072200" in the Makefile.
+
+ */
+#if LIBCURL_VERSION_NUM >= 0x072200
+#define GIT_CURL_HAVE_CURLOPT_LOGIN_OPTIONS 1
+#endif
+
+/**
+ * CURL_SSLVERSION_TLSv1_[012] was added in 7.34.0, released in
+ * December 2013.
+ */
+#if LIBCURL_VERSION_NUM >= 0x072200
+#define GIT_CURL_HAVE_CURL_SSLVERSION_TLSv1_0
+#endif
+
+/**
+ * CURLOPT_PINNEDPUBLICKEY was added in 7.39.0, released in November
+ * 2014.
+ */
+#if LIBCURL_VERSION_NUM >= 0x072c00
+#define GIT_CURL_HAVE_CURLOPT_PINNEDPUBLICKEY 1
+#endif
+
+/**
+ * CURL_HTTP_VERSION_2 was added in 7.43.0, released in June 2015.
+ *
+ * The CURL_HTTP_VERSION_2 alias (but not CURL_HTTP_VERSION_2_0) has
+ * always been a macro, not an enum field (checked on curl version
+ * 7.78.0)
+ */
+#if LIBCURL_VERSION_NUM >= 0x072b00
+#define GIT_CURL_HAVE_CURL_HTTP_VERSION_2 1
+#endif
+
+/**
+ * CURLSSLOPT_NO_REVOKE was added in 7.44.0, released in August 2015.
+ *
+ * The CURLSSLOPT_NO_REVOKE is, has always been a macro, not an enum
+ * field (checked on curl version 7.78.0)
+ */
+#if LIBCURL_VERSION_NUM >= 0x072c00
+#define GIT_CURL_HAVE_CURLSSLOPT_NO_REVOKE 1
+#endif
+
+/**
+ * CURLOPT_PROXY_CAINFO was added in 7.52.0, released in August 2017.
+ */
+#if LIBCURL_VERSION_NUM >= 0x073400
+#define GIT_CURL_HAVE_CURLOPT_PROXY_CAINFO 1
+#endif
+
+/**
+ * CURLOPT_PROXY_{KEYPASSWD,SSLCERT,SSLKEY} was added in 7.52.0,
+ * released in August 2017.
+ */
+#if LIBCURL_VERSION_NUM >= 0x073400
+#define GIT_CURL_HAVE_CURLOPT_PROXY_KEYPASSWD 1
+#endif
+
+/**
+ * CURL_SSLVERSION_TLSv1_3 was added in 7.53.0, released in February
+ * 2017.
+ */
+#if LIBCURL_VERSION_NUM >= 0x073400
+#define GIT_CURL_HAVE_CURL_SSLVERSION_TLSv1_3 1
+#endif
+
+/**
+ * CURLSSLSET_{NO_BACKENDS,OK,TOO_LATE,UNKNOWN_BACKEND} were added in
+ * 7.56.0, released in September 2017.
+ */
+#if LIBCURL_VERSION_NUM >= 0x073800
+#define GIT_CURL_HAVE_CURLSSLSET_NO_BACKENDS
+#endif
+
+#endif
--- a/git-sh-setup.sh
+++ b/git-sh-setup.sh
@ -223,9 +223,6 @@ require_clean_work_tree () {
 		"rewrite branches")
 			gettextln "Cannot rewrite branches: You have unstaged changes." >&2
 			;;
-		"pull with rebase")
-			gettextln "Cannot pull with rebase: You have unstaged changes." >&2
-			;;
 		*)
 			eval_gettextln "Cannot \$action: You have unstaged changes." >&2
 			;;
@ -242,9 +239,6 @@ require_clean_work_tree () {
 			rebase)
 				gettextln "Cannot rebase: Your index contains uncommitted changes." >&2
 				;;
-			"pull with rebase")
-				gettextln "Cannot pull with rebase: Your index contains uncommitted changes." >&2
-				;;
 			*)
 				eval_gettextln "Cannot \$action: Your index contains uncommitted changes." >&2
 				;;
--- a/git-submodule.sh
+++ b/git-submodule.sh
@ -63,11 +63,6 @@ isnumber()
 	n=$(($1 + 0)) 2>/dev/null && test "$n" = "$1"
 }

-# Given a full hex object ID, is this the zero OID?
-is_zero_oid () {
-	echo "$1" | sane_egrep '^0+$' >/dev/null 2>&1
-}
-
 # Sanitize the local git environment for use within a submodule. We
 # can't simply use clear_local_git_env since we want to preserve some
 # of the settings from GIT_CONFIG_PARAMETERS.
--- a/http-backend.c
+++ b/http-backend.c
@ -739,6 +739,7 @@ static int bad_request(struct strbuf *hdr, const struct service_cmd *c)
 int cmd_main(int argc, const char **argv)
 {
 	char *method = getenv("REQUEST_METHOD");
+	const char *proto_header;
 	char *dir;
 	struct service_cmd *cmd = NULL;
 	char *cmd_arg = NULL;
@ -789,6 +790,9 @@ int cmd_main(int argc, const char **argv)
 	http_config();
 	max_request_buffer = git_env_ulong("GIT_HTTP_MAX_REQUEST_BUFFER",
 					   max_request_buffer);
+	proto_header = getenv("HTTP_GIT_PROTOCOL");
+	if (proto_header)
+		setenv(GIT_PROTOCOL_ENVIRONMENT, proto_header, 0);

 	cmd->imp(&hdr, cmd_arg);
 	return 0;
--- a/http.c
+++ b/http.c
@ -1,4 +1,5 @@
 #include "git-compat-util.h"
+#include "git-curl-compat.h"
 #include "http.h"
 #include "config.h"
 #include "pack.h"
@ -47,19 +48,19 @@ static struct {
 	{ "sslv2", CURL_SSLVERSION_SSLv2 },
 	{ "sslv3", CURL_SSLVERSION_SSLv3 },
 	{ "tlsv1", CURL_SSLVERSION_TLSv1 },
-#if LIBCURL_VERSION_NUM >= 0x072200
+#ifdef GIT_CURL_HAVE_CURL_SSLVERSION_TLSv1_0
 	{ "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
 	{ "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
 	{ "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
 #endif
-#if LIBCURL_VERSION_NUM >= 0x073400
+#ifdef GIT_CURL_HAVE_CURL_SSLVERSION_TLSv1_3
 	{ "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
 #endif
 };
 static const char *ssl_key;
 static const char *ssl_capath;
 static const char *curl_no_proxy;
-#if LIBCURL_VERSION_NUM >= 0x072c00
+#ifdef GIT_CURL_HAVE_CURLOPT_PINNEDPUBLICKEY
 static const char *ssl_pinnedkey;
 #endif
 static const char *ssl_cainfo;
@ -373,10 +374,10 @@ static int http_options(const char *var, const char *value, void *cb)
 	}

 	if (!strcmp("http.pinnedpubkey", var)) {
-#if LIBCURL_VERSION_NUM >= 0x072c00
+#ifdef GIT_CURL_HAVE_CURLOPT_PINNEDPUBLICKEY
 		return git_config_pathname(&ssl_pinnedkey, var, value);
 #else
-		warning(_("Public key pinning not supported with cURL < 7.44.0"));
+		warning(_("Public key pinning not supported with cURL < 7.39.0"));
 		return 0;
 #endif
 	}
@ -500,7 +501,7 @@ static int has_cert_password(void)
 	return 1;
 }

-#if LIBCURL_VERSION_NUM >= 0x073400
+#ifdef GIT_CURL_HAVE_CURLOPT_PROXY_KEYPASSWD
 static int has_proxy_cert_password(void)
 {
 	if (http_proxy_ssl_cert == NULL || proxy_ssl_cert_password_required != 1)
@ -516,7 +517,7 @@ static int has_proxy_cert_password(void)
 }
 #endif

-#if LIBCURL_VERSION_NUM >= 0x071900
+#ifdef GITCURL_HAVE_CURLOPT_TCP_KEEPALIVE
 static void set_curl_keepalive(CURL *c)
 {
 	curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
@ -536,7 +537,7 @@ static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 	if (rc < 0)
 		warning_errno("unable to set SO_KEEPALIVE on socket");

-	return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
+	return CURL_SOCKOPT_OK;
 }

 static void set_curl_keepalive(CURL *c)
@ -732,7 +733,7 @@ static long get_curl_allowed_protocols(int from_user)
 	return allowed_protocols;
 }

-#if LIBCURL_VERSION_NUM >=0x072f00
+#ifdef GIT_CURL_HAVE_CURL_HTTP_VERSION_2
 static int get_curl_http_version_opt(const char *version_string, long *opt)
 {
 	int i;
@ -774,7 +775,7 @@ static CURL *get_curl_handle(void)
 		curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 	}

-#if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
+#ifdef GIT_CURL_HAVE_CURL_HTTP_VERSION_2
    if (curl_http_version) {
 		long opt;
 		if (!get_curl_http_version_opt(curl_http_version, &opt)) {
@ -805,7 +806,7 @@ static CURL *get_curl_handle(void)

 	if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 	    !http_schannel_check_revoke) {
-#if LIBCURL_VERSION_NUM >= 0x072c00
+#ifdef GIT_CURL_HAVE_CURLSSLOPT_NO_REVOKE
 		curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
 #else
 		warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
@ -845,20 +846,20 @@ static CURL *get_curl_handle(void)
 		curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 	if (ssl_capath != NULL)
 		curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
-#if LIBCURL_VERSION_NUM >= 0x072c00
+#ifdef GIT_CURL_HAVE_CURLOPT_PINNEDPUBLICKEY
 	if (ssl_pinnedkey != NULL)
 		curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 #endif
 	if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 	    !http_schannel_use_ssl_cainfo) {
 		curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
-#if LIBCURL_VERSION_NUM >= 0x073400
+#ifdef GIT_CURL_HAVE_CURLOPT_PROXY_CAINFO
 		curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
 #endif
 	} else if (ssl_cainfo != NULL || http_proxy_ssl_ca_info != NULL) {
 		if (ssl_cainfo != NULL)
 			curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
-#if LIBCURL_VERSION_NUM >= 0x073400
+#ifdef GIT_CURL_HAVE_CURLOPT_PROXY_CAINFO
 		if (http_proxy_ssl_ca_info != NULL)
 			curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, http_proxy_ssl_ca_info);
 #endif
@ -927,7 +928,6 @@ static CURL *get_curl_handle(void)
 		 */
 		curl_easy_setopt(result, CURLOPT_PROXY, "");
 	} else if (curl_http_proxy) {
-#if LIBCURL_VERSION_NUM >= 0x071800
 		if (starts_with(curl_http_proxy, "socks5h"))
 			curl_easy_setopt(result,
 				CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
@ -940,8 +940,7 @@ static CURL *get_curl_handle(void)
 		else if (starts_with(curl_http_proxy, "socks"))
 			curl_easy_setopt(result,
 				CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
-#endif
-#if LIBCURL_VERSION_NUM >= 0x073400
+#ifdef GIT_CURL_HAVE_CURLOPT_PROXY_KEYPASSWD
 		else if (starts_with(curl_http_proxy, "https")) {
 			curl_easy_setopt(result, CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);

@ -1006,7 +1005,7 @@ void http_init(struct remote *remote, const char *url, int proactive_auth)
 	free(normalized_url);
 	string_list_clear(&config.vars, 1);

-#if LIBCURL_VERSION_NUM >= 0x073800
+#ifdef GIT_CURL_HAVE_CURLSSLSET_NO_BACKENDS
 	if (http_ssl_backend) {
 		const curl_ssl_backend **backends;
 		struct strbuf buf = STRBUF_INIT;
--- a/imap-send.c
+++ b/imap-send.c
@ -1441,7 +1441,7 @@ static CURL *setup_curl(struct imap_server_conf *srvc, struct credential *cred)
 	curl_easy_setopt(curl, CURLOPT_PORT, server.port);

 	if (server.auth_method) {
-#if LIBCURL_VERSION_NUM < 0x072200
+#ifndef GIT_CURL_HAVE_CURLOPT_LOGIN_OPTIONS
 		warning("No LOGIN_OPTIONS support in this cURL version");
 #else
 		struct strbuf auth = STRBUF_INIT;
--- a/ls-refs.c
+++ b/ls-refs.c
@ -171,7 +171,7 @@ int ls_refs(struct repository *r, struct packet_reader *request)
 	if (!data.prefixes.nr)
 		strvec_push(&data.prefixes, "");
 	for_each_fullref_in_prefixes(get_git_namespace(), data.prefixes.v,
-				     send_ref, &data, 0);
+				     send_ref, &data);
 	packet_fflush(stdout);
 	strvec_clear(&data.prefixes);
 	strbuf_release(&data.buf);
--- a/midx.c
+++ b/midx.c
@ -283,14 +283,18 @@ uint32_t nth_midxed_pack_int_id(struct multi_pack_index *m, uint32_t pos)
 			(off_t)pos * MIDX_CHUNK_OFFSET_WIDTH);
 }

-static int nth_midxed_pack_entry(struct repository *r,
-				 struct multi_pack_index *m,
-				 struct pack_entry *e,
-				 uint32_t pos)
+int fill_midx_entry(struct repository * r,
+		    const struct object_id *oid,
+		    struct pack_entry *e,
+		    struct multi_pack_index *m)
 {
+	uint32_t pos;
 	uint32_t pack_int_id;
 	struct packed_git *p;

+	if (!bsearch_midx(oid, m, &pos))
+		return 0;
+
 	if (pos >= m->num_objects)
 		return 0;

@ -310,15 +314,9 @@ static int nth_midxed_pack_entry(struct repository *r,
 	if (!is_pack_valid(p))
 		return 0;

-	if (p->num_bad_objects) {
-		uint32_t i;
-		struct object_id oid;
-		nth_midxed_object_oid(&oid, m, pos);
-		for (i = 0; i < p->num_bad_objects; i++)
-			if (hasheq(oid.hash,
-				   p->bad_object_sha1 + the_hash_algo->rawsz * i))
-				return 0;
-	}
+	if (oidset_size(&p->bad_objects) &&
+	    oidset_contains(&p->bad_objects, oid))
+		return 0;

 	e->offset = nth_midxed_offset(m, pos);
 	e->p = p;
@ -326,19 +324,6 @@ static int nth_midxed_pack_entry(struct repository *r,
 	return 1;
 }

-int fill_midx_entry(struct repository * r,
-		    const struct object_id *oid,
-		    struct pack_entry *e,
-		    struct multi_pack_index *m)
-{
-	uint32_t pos;
-
-	if (!bsearch_midx(oid, m, &pos))
-		return 0;
-
-	return nth_midxed_pack_entry(r, m, e, pos);
-}
-
 /* Match "foo.idx" against either "foo.pack" _or_ "foo.idx". */
 static int cmp_idx_or_pack_name(const char *idx_or_pack_name,
 				const char *idx_name)
--- a/object-file.c
+++ b/object-file.c
@ -1642,7 +1642,7 @@ static int do_oid_object_info_extended(struct repository *r,
 		return 0;
 	rtype = packed_object_info(r, e.p, e.offset, oi);
 	if (rtype < 0) {
-		mark_bad_packed_object(e.p, real->hash);
+		mark_bad_packed_object(e.p, real);
 		return do_oid_object_info_extended(r, real, oi, 0);
 	} else if (oi->whence == OI_PACKED) {
 		oi->u.packed.offset = e.offset;
@ -1751,7 +1751,7 @@ void *read_object_file_extended(struct repository *r,
 		die(_("loose object %s (stored in %s) is corrupt"),
 		    oid_to_hex(repl), path);

-	if ((p = has_packed_and_bad(r, repl->hash)) != NULL)
+	if ((p = has_packed_and_bad(r, repl)) != NULL)
 		die(_("packed object %s (stored in %s) is corrupt"),
 		    oid_to_hex(repl), p->pack_name);
 	obj_read_unlock();
--- a/object-store.h
+++ b/object-store.h
@ -10,6 +10,7 @@
 #include "khash.h"
 #include "dir.h"
 #include "oidtree.h"
+#include "oidset.h"

 struct object_directory {
 	struct object_directory *next;
@ -76,9 +77,8 @@ struct packed_git {
 	const void *index_data;
 	size_t index_size;
 	uint32_t num_objects;
-	uint32_t num_bad_objects;
 	uint32_t crc_offset;
-	unsigned char *bad_object_sha1;
+	struct oidset bad_objects;
 	int index_version;
 	time_t mtime;
 	int pack_fd;
--- a/oidset.c
+++ b/oidset.c
@ -36,11 +36,6 @@ void oidset_clear(struct oidset *set)
 	oidset_init(set, 0);
 }

-int oidset_size(struct oidset *set)
-{
-	return kh_size(&set->set);
-}
-
 void oidset_parse_file(struct oidset *set, const char *path)
 {
 	oidset_parse_file_carefully(set, path, NULL, NULL);
--- a/oidset.h
+++ b/oidset.h
@ -57,7 +57,10 @@ int oidset_remove(struct oidset *set, const struct object_id *oid);
 /**
 * Returns the number of oids in the set.
 */
-int oidset_size(struct oidset *set);
+static inline int oidset_size(const struct oidset *set)
+{
+	return kh_size(&set->set);
+}

 /**
 * Remove all entries from the oidset, freeing any resources associated with
--- a/pack-revindex.h
+++ b/pack-revindex.h
@ -109,7 +109,7 @@ off_t pack_pos_to_offset(struct packed_git *p, uint32_t pos);
 * If the reverse index has not yet been loaded, or the position is out of
 * bounds, this function aborts.
 *
- * This function runs in time O(log N) with the number of objects in the MIDX.
+ * This function runs in constant time.
 */
 uint32_t pack_pos_to_midx(struct multi_pack_index *m, uint32_t pos);

@ -120,7 +120,7 @@ uint32_t pack_pos_to_midx(struct multi_pack_index *m, uint32_t pos);
 * If the reverse index has not yet been loaded, or the position is out of
 * bounds, this function aborts.
 *
- * This function runs in constant time.
+ * This function runs in time O(log N) with the number of objects in the MIDX.
 */
 int midx_to_pack_pos(struct multi_pack_index *midx, uint32_t at, uint32_t *pos);

--- a/packfile.c
+++ b/packfile.c
@ -1161,31 +1161,19 @@ int unpack_object_header(struct packed_git *p,
 	return type;
 }

-void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1)
+void mark_bad_packed_object(struct packed_git *p, const struct object_id *oid)
 {
-	unsigned i;
-	const unsigned hashsz = the_hash_algo->rawsz;
-	for (i = 0; i < p->num_bad_objects; i++)
-		if (hasheq(sha1, p->bad_object_sha1 + hashsz * i))
-			return;
-	p->bad_object_sha1 = xrealloc(p->bad_object_sha1,
-				      st_mult(GIT_MAX_RAWSZ,
-					      st_add(p->num_bad_objects, 1)));
-	hashcpy(p->bad_object_sha1 + hashsz * p->num_bad_objects, sha1);
-	p->num_bad_objects++;
+	oidset_insert(&p->bad_objects, oid);
 }

 const struct packed_git *has_packed_and_bad(struct repository *r,
-					    const unsigned char *sha1)
+					    const struct object_id *oid)
 {
 	struct packed_git *p;
-	unsigned i;

 	for (p = r->objects->packed_git; p; p = p->next)
-		for (i = 0; i < p->num_bad_objects; i++)
-			if (hasheq(sha1,
-				   p->bad_object_sha1 + the_hash_algo->rawsz * i))
-				return p;
+		if (oidset_contains(&p->bad_objects, oid))
+			return p;
 	return NULL;
 }

@ -1272,7 +1260,7 @@ static int retry_bad_packed_offset(struct repository *r,
 	if (offset_to_pack_pos(p, obj_offset, &pos) < 0)
 		return OBJ_BAD;
 	nth_packed_object_id(&oid, p, pack_pos_to_index(p, pos));
-	mark_bad_packed_object(p, oid.hash);
+	mark_bad_packed_object(p, &oid);
 	type = oid_object_info(r, &oid, NULL);
 	if (type <= OBJ_NONE)
 		return OBJ_BAD;
@ -1722,7 +1710,7 @@ void *unpack_entry(struct repository *r, struct packed_git *p, off_t obj_offset,
 				nth_packed_object_id(&oid, p, index_pos);
 				error("bad packed object CRC for %s",
 				      oid_to_hex(&oid));
-				mark_bad_packed_object(p, oid.hash);
+				mark_bad_packed_object(p, &oid);
 				data = NULL;
 				goto out;
 			}
@ -1811,7 +1799,7 @@ void *unpack_entry(struct repository *r, struct packed_git *p, off_t obj_offset,
 				      " at offset %"PRIuMAX" from %s",
 				      oid_to_hex(&base_oid), (uintmax_t)obj_offset,
 				      p->pack_name);
-				mark_bad_packed_object(p, base_oid.hash);
+				mark_bad_packed_object(p, &base_oid);
 				base = read_object(r, &base_oid, &type, &base_size);
 				external_base = base;
 			}
@ -2016,13 +2004,9 @@ static int fill_pack_entry(const struct object_id *oid,
 {
 	off_t offset;

-	if (p->num_bad_objects) {
-		unsigned i;
-		for (i = 0; i < p->num_bad_objects; i++)
-			if (hasheq(oid->hash,
-				   p->bad_object_sha1 + the_hash_algo->rawsz * i))
-				return 0;
-	}
+	if (oidset_size(&p->bad_objects) &&
+	    oidset_contains(&p->bad_objects, oid))
+		return 0;

 	offset = find_pack_entry_one(oid->hash, p);
 	if (!offset)
--- a/packfile.h
+++ b/packfile.h
@ -159,8 +159,8 @@ int packed_object_info(struct repository *r,
 		       struct packed_git *pack,
 		       off_t offset, struct object_info *);

-void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
-const struct packed_git *has_packed_and_bad(struct repository *r, const unsigned char *sha1);
+void mark_bad_packed_object(struct packed_git *, const struct object_id *);
+const struct packed_git *has_packed_and_bad(struct repository *, const struct object_id *);

 #define ON_DISK_KEEP_PACKS 1
 #define IN_CORE_KEEP_PACKS 2
--- a/parse-options.c
+++ b/parse-options.c
@ -310,19 +310,6 @@ static enum parse_opt_result parse_long_opt(
 again:
 		if (!skip_prefix(arg, long_name, &rest))
 			rest = NULL;
-		if (options->type == OPTION_ARGUMENT) {
-			if (!rest)
-				continue;
-			if (*rest == '=')
-				return error(_("%s takes no value"),
-					     optname(options, flags));
-			if (*rest)
-				continue;
-			if (options->value)
-				*(int *)options->value = options->defval;
-			p->out[p->cpidx++] = arg - 2;
-			return PARSE_OPT_DONE;
-		}
 		if (!rest) {
 			/* abbreviated? */
 			if (!(p->flags & PARSE_OPT_KEEP_UNKNOWN) &&
--- a/parse-options.h
+++ b/parse-options.h
@ -8,7 +8,6 @@
 enum parse_opt_type {
 	/* special types */
 	OPTION_END,
-	OPTION_ARGUMENT,
 	OPTION_GROUP,
 	OPTION_NUMBER,
 	OPTION_ALIAS,
@ -155,8 +154,6 @@ struct option {
 #define OPT_INTEGER_F(s, l, v, h, f)     { OPTION_INTEGER, (s), (l), (v), N_("n"), (h), (f) }

 #define OPT_END()                   { OPTION_END }
-#define OPT_ARGUMENT(l, v, h)       { OPTION_ARGUMENT, 0, (l), (v), NULL, \
-				      (h), PARSE_OPT_NOARG, NULL, 1 }
 #define OPT_GROUP(h)                { OPTION_GROUP, 0, NULL, NULL, NULL, (h) }
 #define OPT_BIT(s, l, v, h, b)      OPT_BIT_F(s, l, v, h, b, 0)
 #define OPT_BITOP(s, l, v, h, set, clear) { OPTION_BITOP, (s), (l), (v), NULL, (h), \
--- a/ref-filter.c
+++ b/ref-filter.c
@ -2100,8 +2100,7 @@ static int filter_pattern_match(struct ref_filter *filter, const char *refname)
 */
 static int for_each_fullref_in_pattern(struct ref_filter *filter,
 				       each_ref_fn cb,
-				       void *cb_data,
-				       int broken)
+				       void *cb_data)
 {
 	if (!filter->match_as_path) {
 		/*
@ -2109,7 +2108,7 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
 		 * prefixes like "refs/heads/" etc. are stripped off,
 		 * so we have to look at everything:
 		 */
-		return for_each_fullref_in("", cb, cb_data, broken);
+		return for_each_fullref_in("", cb, cb_data);
 	}

 	if (filter->ignore_case) {
@ -2118,16 +2117,16 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
 		 * so just return everything and let the caller
 		 * sort it out.
 		 */
-		return for_each_fullref_in("", cb, cb_data, broken);
+		return for_each_fullref_in("", cb, cb_data);
 	}

 	if (!filter->name_patterns[0]) {
 		/* no patterns; we have to look at everything */
-		return for_each_fullref_in("", cb, cb_data, broken);
+		return for_each_fullref_in("", cb, cb_data);
 	}

 	return for_each_fullref_in_prefixes(NULL, filter->name_patterns,
-					    cb, cb_data, broken);
+					    cb, cb_data);
 }

 /*
@ -2405,13 +2404,10 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 {
 	struct ref_filter_cbdata ref_cbdata;
 	int ret = 0;
-	unsigned int broken = 0;

 	ref_cbdata.array = array;
 	ref_cbdata.filter = filter;

-	if (type & FILTER_REFS_INCLUDE_BROKEN)
-		broken = 1;
 	filter->kind = type & FILTER_REFS_KIND_MASK;

 	init_contains_cache(&ref_cbdata.contains_cache);
@ -2428,13 +2424,13 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 		 * of filter_ref_kind().
 		 */
 		if (filter->kind == FILTER_REFS_BRANCHES)
-			ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata, broken);
+			ret = for_each_fullref_in("refs/heads/", ref_filter_handler, &ref_cbdata);
 		else if (filter->kind == FILTER_REFS_REMOTES)
-			ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata, broken);
+			ret = for_each_fullref_in("refs/remotes/", ref_filter_handler, &ref_cbdata);
 		else if (filter->kind == FILTER_REFS_TAGS)
-			ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata, broken);
+			ret = for_each_fullref_in("refs/tags/", ref_filter_handler, &ref_cbdata);
 		else if (filter->kind & FILTER_REFS_ALL)
-			ret = for_each_fullref_in_pattern(filter, ref_filter_handler, &ref_cbdata, broken);
+			ret = for_each_fullref_in_pattern(filter, ref_filter_handler, &ref_cbdata);
 		if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
 			head_ref(ref_filter_handler, &ref_cbdata);
 	}
--- a/ref-filter.h
+++ b/ref-filter.h
@ -13,7 +13,6 @@
 #define QUOTE_PYTHON 4
 #define QUOTE_TCL 8

-#define FILTER_REFS_INCLUDE_BROKEN 0x0001
 #define FILTER_REFS_TAGS           0x0002
 #define FILTER_REFS_BRANCHES       0x0004
 #define FILTER_REFS_REMOTES        0x0008
--- a/refs.c
+++ b/refs.c
@ -1413,14 +1413,21 @@ int head_ref(each_ref_fn fn, void *cb_data)

 struct ref_iterator *refs_ref_iterator_begin(
 		struct ref_store *refs,
-		const char *prefix, int trim, int flags)
+		const char *prefix, int trim,
+		enum do_for_each_ref_flags flags)
 {
 	struct ref_iterator *iter;

-	if (ref_paranoia < 0)
-		ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
-	if (ref_paranoia)
-		flags |= DO_FOR_EACH_INCLUDE_BROKEN;
+	if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
+		static int ref_paranoia = -1;
+
+		if (ref_paranoia < 0)
+			ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 1);
+		if (ref_paranoia) {
+			flags |= DO_FOR_EACH_INCLUDE_BROKEN;
+			flags |= DO_FOR_EACH_OMIT_DANGLING_SYMREFS;
+		}
+	}

 	iter = refs->be->iterator_begin(refs, prefix, flags);

@ -1479,7 +1486,8 @@ static int do_for_each_ref_helper(struct repository *r,
 }

 static int do_for_each_ref(struct ref_store *refs, const char *prefix,
-			   each_ref_fn fn, int trim, int flags, void *cb_data)
+			   each_ref_fn fn, int trim,
+			   enum do_for_each_ref_flags flags, void *cb_data)
 {
 	struct ref_iterator *iter;
 	struct do_for_each_ref_help hp = { fn, cb_data };
@ -1514,25 +1522,16 @@ int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
 	return refs_for_each_ref_in(get_main_ref_store(the_repository), prefix, fn, cb_data);
 }

-int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken)
+int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data)
 {
-	unsigned int flag = 0;
-
-	if (broken)
-		flag = DO_FOR_EACH_INCLUDE_BROKEN;
 	return do_for_each_ref(get_main_ref_store(the_repository),
-			       prefix, fn, 0, flag, cb_data);
+			       prefix, fn, 0, 0, cb_data);
 }

 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
-			     each_ref_fn fn, void *cb_data,
-			     unsigned int broken)
+			     each_ref_fn fn, void *cb_data)
 {
-	unsigned int flag = 0;
-
-	if (broken)
-		flag = DO_FOR_EACH_INCLUDE_BROKEN;
-	return do_for_each_ref(refs, prefix, fn, 0, flag, cb_data);
+	return do_for_each_ref(refs, prefix, fn, 0, 0, cb_data);
 }

 int for_each_replace_ref(struct repository *r, each_repo_ref_fn fn, void *cb_data)
@ -1624,8 +1623,7 @@ static void find_longest_prefixes(struct string_list *out,

 int for_each_fullref_in_prefixes(const char *namespace,
 				 const char **patterns,
-				 each_ref_fn fn, void *cb_data,
-				 unsigned int broken)
+				 each_ref_fn fn, void *cb_data)
 {
 	struct string_list prefixes = STRING_LIST_INIT_DUP;
 	struct string_list_item *prefix;
@ -1640,7 +1638,7 @@ int for_each_fullref_in_prefixes(const char *namespace,

 	for_each_string_list_item(prefix, &prefixes) {
 		strbuf_addstr(&buf, prefix->string);
-		ret = for_each_fullref_in(buf.buf, fn, cb_data, broken);
+		ret = for_each_fullref_in(buf.buf, fn, cb_data);
 		if (ret)
 			break;
 		strbuf_setlen(&buf, namespace_len);
--- a/refs.h
+++ b/refs.h
@ -342,10 +342,8 @@ int for_each_ref(each_ref_fn fn, void *cb_data);
 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);

 int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
-			     each_ref_fn fn, void *cb_data,
-			     unsigned int broken);
-int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
-			unsigned int broken);
+			     each_ref_fn fn, void *cb_data);
+int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data);

 /**
 * iterate all refs in "patterns" by partitioning patterns into disjoint sets
@ -354,8 +352,7 @@ int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
 * callers should be prepared to ignore references that they did not ask for.
 */
 int for_each_fullref_in_prefixes(const char *namespace, const char **patterns,
-				 each_ref_fn fn, void *cb_data,
-				 unsigned int broken);
+				 each_ref_fn fn, void *cb_data);
 /**
 * iterate refs from the respective area.
 */
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@ -744,6 +744,11 @@ static int files_ref_iterator_advance(struct ref_iterator *ref_iterator)
 		    ref_type(iter->iter0->refname) != REF_TYPE_PER_WORKTREE)
 			continue;

+		if ((iter->flags & DO_FOR_EACH_OMIT_DANGLING_SYMREFS) &&
+		    (iter->iter0->flags & REF_ISSYMREF) &&
+		    (iter->iter0->flags & REF_ISBROKEN))
+			continue;
+
 		if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
 		    !ref_resolves_to_object(iter->iter0->refname,
 					    iter->iter0->oid,
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@ -245,8 +245,36 @@ int refs_rename_ref_available(struct ref_store *refs,
 /* We allow "recursive" symbolic refs. Only within reason, though */
 #define SYMREF_MAXDEPTH 5

-/* Include broken references in a do_for_each_ref*() iteration: */
-#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
+/*
+ * These flags are passed to refs_ref_iterator_begin() (and do_for_each_ref(),
+ * which feeds it).
+ */
+enum do_for_each_ref_flags {
+	/*
+	 * Include broken references in a do_for_each_ref*() iteration, which
+	 * would normally be omitted. This includes both refs that point to
+	 * missing objects (a true repository corruption), ones with illegal
+	 * names (which we prefer not to expose to callers), as well as
+	 * dangling symbolic refs (i.e., those that point to a non-existent
+	 * ref; this is not a corruption, but as they have no valid oid, we
+	 * omit them from normal iteration results).
+	 */
+	DO_FOR_EACH_INCLUDE_BROKEN = (1 << 0),
+
+	/*
+	 * Only include per-worktree refs in a do_for_each_ref*() iteration.
+	 * Normally this will be used with a files ref_store, since that's
+	 * where all reference backends will presumably store their
+	 * per-worktree refs.
+	 */
+	DO_FOR_EACH_PER_WORKTREE_ONLY = (1 << 1),
+
+	/*
+	 * Omit dangling symrefs from output; this only has an effect with
+	 * INCLUDE_BROKEN, since they are otherwise not included at all.
+	 */
+	DO_FOR_EACH_OMIT_DANGLING_SYMREFS = (1 << 2),
+};

 /*
 * Reference iterators
@ -349,16 +377,12 @@ int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
 * Return an iterator that goes over each reference in `refs` for
 * which the refname begins with prefix. If trim is non-zero, then
 * trim that many characters off the beginning of each refname.
- * The output is ordered by refname. The following flags are supported:
- *
- * DO_FOR_EACH_INCLUDE_BROKEN: include broken references in
- *         the iteration.
- *
- * DO_FOR_EACH_PER_WORKTREE_ONLY: only produce REF_TYPE_PER_WORKTREE refs.
+ * The output is ordered by refname.
 */
 struct ref_iterator *refs_ref_iterator_begin(
 		struct ref_store *refs,
-		const char *prefix, int trim, int flags);
+		const char *prefix, int trim,
+		enum do_for_each_ref_flags flags);

 /*
 * A callback function used to instruct merge_ref_iterator how to
@ -446,10 +470,8 @@ void base_ref_iterator_free(struct ref_iterator *iter);
 /*
 * backend-specific implementation of ref_iterator_advance. For symrefs, the
 * function should set REF_ISSYMREF, and it should also dereference the symref
- * to provide the OID referent. If DO_FOR_EACH_INCLUDE_BROKEN is set, symrefs
- * with non-existent referents and refs pointing to non-existent object names
- * should also be returned. If DO_FOR_EACH_PER_WORKTREE_ONLY, only
- * REF_TYPE_PER_WORKTREE refs should be returned.
+ * to provide the OID referent. It should respect do_for_each_ref_flags
+ * that were passed to refs_ref_iterator_begin().
 */
 typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);

@ -498,14 +520,6 @@ int do_for_each_repo_ref_iterator(struct repository *r,
 				  struct ref_iterator *iter,
 				  each_repo_ref_fn fn, void *cb_data);

-/*
- * Only include per-worktree refs in a do_for_each_ref*() iteration.
- * Normally this will be used with a files ref_store, since that's
- * where all reference backends will presumably store their
- * per-worktree refs.
- */
-#define DO_FOR_EACH_PER_WORKTREE_ONLY 0x02
-
 struct ref_store;

 /* refs backends */
--- a/repository.c
+++ b/repository.c
@ -216,8 +216,7 @@ int repo_submodule_init(struct repository *subrepo,
 		}

 		strbuf_reset(&gitdir);
-		strbuf_repo_git_path(&gitdir, superproject,
-				     "modules/%s", sub->name);
+		submodule_name_to_gitdir(&gitdir, superproject, sub->name);

 		if (repo_init(subrepo, gitdir.buf, NULL)) {
 			ret = -1;
--- a/revision.c
+++ b/revision.c
@ -2548,7 +2548,7 @@ static int for_each_bisect_ref(struct ref_store *refs, each_ref_fn fn,
 	struct strbuf bisect_refs = STRBUF_INIT;
 	int status;
 	strbuf_addf(&bisect_refs, "refs/bisect/%s", term);
-	status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data, 0);
+	status = refs_for_each_fullref_in(refs, bisect_refs.buf, fn, cb_data);
 	strbuf_release(&bisect_refs);
 	return status;
 }
--- a/run-command.c
+++ b/run-command.c
@ -211,9 +211,9 @@ static char *locate_in_PATH(const char *file)
 	return NULL;
 }

-static int exists_in_PATH(const char *file)
+int exists_in_PATH(const char *command)
 {
-	char *r = locate_in_PATH(file);
+	char *r = locate_in_PATH(command);
 	int found = r != NULL;
 	free(r);
 	return found;
--- a/run-command.h
+++ b/run-command.h
@ -190,6 +190,18 @@ void child_process_clear(struct child_process *);

 int is_executable(const char *name);

+/**
+ * Check if the command exists on $PATH. This emulates the path search that
+ * execvp would perform, without actually executing the command so it
+ * can be used before fork() to prepare to run a command using
+ * execve() or after execvp() to diagnose why it failed.
+ *
+ * The caller should ensure that command contains no directory separators.
+ *
+ * Returns 1 if it is found in $PATH or 0 if the command could not be found.
+ */
+int exists_in_PATH(const char *command);
+
 /**
 * Start a sub-process. Takes a pointer to a `struct child_process`
 * that specifies the details and returns pipe FDs (if requested).
--- a/strvec.h
+++ b/strvec.h
@ -29,8 +29,8 @@ extern const char *empty_strvec[];
 */
 struct strvec {
 	const char **v;
-	int nr;
-	int alloc;
+	size_t nr;
+	size_t alloc;
 };

 #define STRVEC_INIT { empty_strvec, 0, 0 }
--- a/submodule.c
+++ b/submodule.c
@ -1845,14 +1845,16 @@ out:

 void submodule_unset_core_worktree(const struct submodule *sub)
 {
-	char *config_path = xstrfmt("%s/modules/%s/config",
-				    get_git_dir(), sub->name);
+	struct strbuf config_path = STRBUF_INIT;

-	if (git_config_set_in_file_gently(config_path, "core.worktree", NULL))
+	submodule_name_to_gitdir(&config_path, the_repository, sub->name);
+	strbuf_addstr(&config_path, "/config");
+
+	if (git_config_set_in_file_gently(config_path.buf, "core.worktree", NULL))
 		warning(_("Could not unset core.worktree setting in submodule '%s'"),
 			  sub->path);

-	free(config_path);
+	strbuf_release(&config_path);
 }

 static const char *get_super_prefix_or_empty(void)
@ -1948,20 +1950,22 @@ int submodule_move_head(const char *path,
 				absorb_git_dir_into_superproject(path,
 					ABSORB_GITDIR_RECURSE_SUBMODULES);
 		} else {
-			char *gitdir = xstrfmt("%s/modules/%s",
-				    get_git_dir(), sub->name);
-			connect_work_tree_and_git_dir(path, gitdir, 0);
-			free(gitdir);
+			struct strbuf gitdir = STRBUF_INIT;
+			submodule_name_to_gitdir(&gitdir, the_repository,
+						 sub->name);
+			connect_work_tree_and_git_dir(path, gitdir.buf, 0);
+			strbuf_release(&gitdir);

 			/* make sure the index is clean as well */
 			submodule_reset_index(path);
 		}

 		if (old_head && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
-			char *gitdir = xstrfmt("%s/modules/%s",
-				    get_git_dir(), sub->name);
-			connect_work_tree_and_git_dir(path, gitdir, 1);
-			free(gitdir);
+			struct strbuf gitdir = STRBUF_INIT;
+			submodule_name_to_gitdir(&gitdir, the_repository,
+						 sub->name);
+			connect_work_tree_and_git_dir(path, gitdir.buf, 1);
+			strbuf_release(&gitdir);
 		}
 	}

@ -2076,7 +2080,7 @@ int validate_submodule_git_dir(char *git_dir, const char *submodule_name)
 static void relocate_single_git_dir_into_superproject(const char *path)
 {
 	char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
-	char *new_git_dir;
+	struct strbuf new_gitdir = STRBUF_INIT;
 	const struct submodule *sub;

 	if (submodule_uses_worktrees(path))
@ -2094,14 +2098,13 @@ static void relocate_single_git_dir_into_superproject(const char *path)
 	if (!sub)
 		die(_("could not lookup name for submodule '%s'"), path);

-	new_git_dir = git_pathdup("modules/%s", sub->name);
-	if (validate_submodule_git_dir(new_git_dir, sub->name) < 0)
+	submodule_name_to_gitdir(&new_gitdir, the_repository, sub->name);
+	if (validate_submodule_git_dir(new_gitdir.buf, sub->name) < 0)
 		die(_("refusing to move '%s' into an existing git dir"),
 		    real_old_git_dir);
-	if (safe_create_leading_directories_const(new_git_dir) < 0)
-		die(_("could not create directory '%s'"), new_git_dir);
-	real_new_git_dir = real_pathdup(new_git_dir, 1);
-	free(new_git_dir);
+	if (safe_create_leading_directories_const(new_gitdir.buf) < 0)
+		die(_("could not create directory '%s'"), new_gitdir.buf);
+	real_new_git_dir = real_pathdup(new_gitdir.buf, 1);

 	fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
 		get_super_prefix_or_empty(), path,
@ -2112,6 +2115,7 @@ static void relocate_single_git_dir_into_superproject(const char *path)
 	free(old_git_dir);
 	free(real_old_git_dir);
 	free(real_new_git_dir);
+	strbuf_release(&new_gitdir);
 }

 /*
@ -2131,6 +2135,7 @@ void absorb_git_dir_into_superproject(const char *path,
 	/* Not populated? */
 	if (!sub_git_dir) {
 		const struct submodule *sub;
+		struct strbuf sub_gitdir = STRBUF_INIT;

 		if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
 			/* unpopulated as expected */
@ -2152,8 +2157,9 @@ void absorb_git_dir_into_superproject(const char *path,
 		sub = submodule_from_path(the_repository, null_oid(), path);
 		if (!sub)
 			die(_("could not lookup name for submodule '%s'"), path);
-		connect_work_tree_and_git_dir(path,
-			git_path("modules/%s", sub->name), 0);
+		submodule_name_to_gitdir(&sub_gitdir, the_repository, sub->name);
+		connect_work_tree_and_git_dir(path, sub_gitdir.buf, 0);
+		strbuf_release(&sub_gitdir);
 	} else {
 		/* Is it already absorbed into the superprojects git dir? */
 		char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
@ -2304,9 +2310,36 @@ int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
 			goto cleanup;
 		}
 		strbuf_reset(buf);
-		strbuf_git_path(buf, "%s/%s", "modules", sub->name);
+		submodule_name_to_gitdir(buf, the_repository, sub->name);
 	}

 cleanup:
 	return ret;
 }
+
+void submodule_name_to_gitdir(struct strbuf *buf, struct repository *r,
+			      const char *submodule_name)
+{
+	/*
+	 * NEEDSWORK: The current way of mapping a submodule's name to
+	 * its location in .git/modules/ has problems with some naming
+	 * schemes. For example, if a submodule is named "foo" and
+	 * another is named "foo/bar" (whether present in the same
+	 * superproject commit or not - the problem will arise if both
+	 * superproject commits have been checked out at any point in
+	 * time), or if two submodule names only have different cases in
+	 * a case-insensitive filesystem.
+	 *
+	 * There are several solutions, including encoding the path in
+	 * some way, introducing a submodule.<name>.gitdir config in
+	 * .git/config (not .gitmodules) that allows overriding what the
+	 * gitdir of a submodule would be (and teach Git, upon noticing
+	 * a clash, to automatically determine a non-clashing name and
+	 * to write such a config), or introducing a
+	 * submodule.<name>.gitdir config in .gitmodules that repo
+	 * administrators can explicitly set. Nothing has been decided,
+	 * so for now, just append the name at the end of the path.
+	 */
+	strbuf_repo_git_path(buf, r, "modules/");
+	strbuf_addstr(buf, submodule_name);
+}
--- a/submodule.h
+++ b/submodule.h
@ -132,6 +132,13 @@ int push_unpushed_submodules(struct repository *r,
 */
 int submodule_to_gitdir(struct strbuf *buf, const char *submodule);

+/*
+ * Given a submodule name, create a path to where the submodule's gitdir lives
+ * inside of the provided repository's 'modules' directory.
+ */
+void submodule_name_to_gitdir(struct strbuf *buf, struct repository *r,
+			      const char *submodule_name);
+
 /*
 * Make sure that no submodule's git dir is nested in a sibling submodule's.
 */
--- a/t/helper/test-parse-options.c
+++ b/t/helper/test-parse-options.c
@ -134,7 +134,6 @@ int cmd__parse_options(int argc, const char **argv)
 		OPT_NOOP_NOARG(0, "obsolete"),
 		OPT_STRING_LIST(0, "list", &list, "str", "add str to list"),
 		OPT_GROUP("Magic arguments"),
-		OPT_ARGUMENT("quux", NULL, "means --quux"),
 		OPT_NUMBER_CALLBACK(&integer, "set integer to NUM",
 			number_callback),
 		{ OPTION_COUNTUP, '+', NULL, &boolean, NULL, "same as -b",
--- a/t/helper/test-run-command.c
+++ b/t/helper/test-run-command.c
@ -61,7 +61,7 @@ struct testsuite {
 	int quiet, immediate, verbose, verbose_log, trace, write_junit_xml;
 };
 #define TESTSUITE_INIT \
-	{ STRING_LIST_INIT_DUP, STRING_LIST_INIT_DUP, -1, 0, 0, 0, 0, 0, 0 }
+	{ STRING_LIST_INIT_DUP, STRING_LIST_INIT_DUP, 0, 0, 0, 0, 0, 0, 0 }

 static int next_test(struct child_process *cp, struct strbuf *err, void *cb,
 		     void **task_cb)
@ -142,9 +142,6 @@ static int testsuite(int argc, const char **argv)
 		OPT_END()
 	};

-	memset(&suite, 0, sizeof(suite));
-	suite.tests.strdup_strings = suite.failed.strdup_strings = 1;
-
 	argc = parse_options(argc, argv, NULL, options,
 			testsuite_usage, PARSE_OPT_STOP_AT_NON_OPTION);

--- a/t/lib-httpd/apache.conf
+++ b/t/lib-httpd/apache.conf
@ -81,8 +81,6 @@ PassEnv GIT_TRACE
 PassEnv GIT_CONFIG_NOSYSTEM
 PassEnv GIT_TEST_SIDEBAND_ALL

-SetEnvIf Git-Protocol ".*" GIT_PROTOCOL=$0
-
 Alias /dumb/ www/
 Alias /auth/dumb/ www/auth/dumb/

@ -117,6 +115,11 @@ Alias /auth/dumb/ www/auth/dumb/
 	SetEnv GIT_EXEC_PATH ${GIT_EXEC_PATH}
 	SetEnv GIT_HTTP_EXPORT_ALL
 </LocationMatch>
+<LocationMatch /smart_v0/>
+	SetEnv GIT_EXEC_PATH ${GIT_EXEC_PATH}
+	SetEnv GIT_HTTP_EXPORT_ALL
+	SetEnv GIT_PROTOCOL
+</LocationMatch>
 ScriptAlias /smart/incomplete_length/git-upload-pack incomplete-length-upload-pack-v2-http.sh/
 ScriptAlias /smart/incomplete_body/git-upload-pack incomplete-body-upload-pack-v2-http.sh/
 ScriptAliasMatch /error_git_upload_pack/(.*)/git-upload-pack error.sh/
--- a/t/t0000-basic.sh
+++ b/t/t0000-basic.sh
@ -1271,28 +1271,29 @@ P=$(test_oid root)

 test_expect_success 'git commit-tree records the correct tree in a commit' '
 	commit0=$(echo NO | git commit-tree $P) &&
-	tree=$(git show --pretty=raw $commit0 |
-		 sed -n -e "s/^tree //p" -e "/^author /q") &&
+	git show --pretty=raw $commit0 >out &&
+	tree=$(sed -n -e "s/^tree //p" -e "/^author /q" out) &&
 	test "z$tree" = "z$P"
 '

 test_expect_success 'git commit-tree records the correct parent in a commit' '
 	commit1=$(echo NO | git commit-tree $P -p $commit0) &&
-	parent=$(git show --pretty=raw $commit1 |
-		sed -n -e "s/^parent //p" -e "/^author /q") &&
+	git show --pretty=raw $commit1 >out &&
+	parent=$(sed -n -e "s/^parent //p" -e "/^author /q" out) &&
 	test "z$commit0" = "z$parent"
 '

 test_expect_success 'git commit-tree omits duplicated parent in a commit' '
 	commit2=$(echo NO | git commit-tree $P -p $commit0 -p $commit0) &&
-	     parent=$(git show --pretty=raw $commit2 |
-		sed -n -e "s/^parent //p" -e "/^author /q" |
-		sort -u) &&
+	git show --pretty=raw $commit2 >out &&
+	cat >match.sed <<-\EOF &&
+	s/^parent //p
+	/^author /q
+	EOF
+	parent=$(sed -n -f match.sed out | sort -u) &&
 	test "z$commit0" = "z$parent" &&
-	numparent=$(git show --pretty=raw $commit2 |
-		sed -n -e "s/^parent //p" -e "/^author /q" |
-		wc -l) &&
-	test $numparent = 1
+	git show --pretty=raw $commit2 >out &&
+	test_stdout_line_count = 1 sed -n -f match.sed out
 '

 test_expect_success 'update-index D/F conflict' '
--- a/t/t0012-help.sh
+++ b/t/t0012-help.sh
@ -73,6 +73,22 @@ test_expect_success 'git help -g' '
 	test_i18ngrep "^   tutorial   " help.output
 '

+test_expect_success 'git help fails for non-existing html pages' '
+	configure_help &&
+	mkdir html-empty &&
+	test_must_fail git -c help.htmlpath=html-empty help status &&
+	test_must_be_empty test-browser.log
+'
+
+test_expect_success 'git help succeeds without git.html' '
+	configure_help &&
+	mkdir html-with-docs &&
+	touch html-with-docs/git-status.html &&
+	git -c help.htmlpath=html-with-docs help status &&
+	echo "html-with-docs/git-status.html" >expect &&
+	test_cmp expect test-browser.log
+'
+
 test_expect_success 'generate builtin list' '
 	git --list-cmds=builtins >builtins
 '
--- a/t/t0040-parse-options.sh
+++ b/t/t0040-parse-options.sh
@ -37,7 +37,6 @@ String options
    --list <str>          add str to list

 Magic arguments
-    --quux                means --quux
    -NUM                  set integer to NUM
    +                     same as -b
    --ambiguous           positive ambiguity
@ -263,10 +262,6 @@ test_expect_success 'detect possible typos' '
 	test_cmp typo.err output.err
 '

-test_expect_success 'keep some options as arguments' '
-	test-tool parse-options --expect="arg 00: --quux" --quux
-'
-
 cat >expect <<\EOF
 Callback: "four", 0
 boolean: 5
--- a/t/t0090-cache-tree.sh
+++ b/t/t0090-cache-tree.sh
@ -195,6 +195,7 @@ test_expect_success 'reset --hard gives cache-tree' '

 test_expect_success 'reset --hard without index gives cache-tree' '
 	rm -f .git/index &&
+	git clean -fd &&
 	git reset --hard &&
 	test_cache_tree
 '
--- a/t/t0301-credential-cache.sh
+++ b/t/t0301-credential-cache.sh
@ -9,6 +9,21 @@ test -z "$NO_UNIX_SOCKETS" || {
 	test_done
 }

+uname_s=$(uname -s)
+case $uname_s in
+*MINGW*)
+	test_path_is_socket () {
+		# `test -S` cannot detect Win10's Unix sockets
+		test_path_exists "$1"
+	}
+	;;
+*)
+	test_path_is_socket () {
+		test -S "$1"
+	}
+	;;
+esac
+
 # don't leave a stale daemon running
 test_atexit 'git credential-cache exit'

@ -21,7 +36,7 @@ test_expect_success 'socket defaults to ~/.cache/git/credential/socket' '
 		rmdir -p .cache/git/credential/
 	" &&
 	test_path_is_missing "$HOME/.git-credential-cache" &&
-	test -S "$HOME/.cache/git/credential/socket"
+	test_path_is_socket "$HOME/.cache/git/credential/socket"
 '

 XDG_CACHE_HOME="$HOME/xdg"
@ -31,7 +46,7 @@ helper_test cache

 test_expect_success "use custom XDG_CACHE_HOME if set and default sockets are not created" '
 	test_when_finished "git credential-cache exit" &&
-	test -S "$XDG_CACHE_HOME/git/credential/socket" &&
+	test_path_is_socket "$XDG_CACHE_HOME/git/credential/socket" &&
 	test_path_is_missing "$HOME/.git-credential-cache/socket" &&
 	test_path_is_missing "$HOME/.cache/git/credential/socket"
 '
@ -48,7 +63,7 @@ test_expect_success 'credential-cache --socket option overrides default location
 	username=store-user
 	password=store-pass
 	EOF
-	test -S "$HOME/dir/socket"
+	test_path_is_socket "$HOME/dir/socket"
 '

 test_expect_success "use custom XDG_CACHE_HOME even if xdg socket exists" '
@ -62,7 +77,7 @@ test_expect_success "use custom XDG_CACHE_HOME even if xdg socket exists" '
 	username=store-user
 	password=store-pass
 	EOF
-	test -S "$HOME/.cache/git/credential/socket" &&
+	test_path_is_socket "$HOME/.cache/git/credential/socket" &&
 	XDG_CACHE_HOME="$HOME/xdg" &&
 	export XDG_CACHE_HOME &&
 	check approve cache <<-\EOF &&
@ -71,7 +86,7 @@ test_expect_success "use custom XDG_CACHE_HOME even if xdg socket exists" '
 	username=store-user
 	password=store-pass
 	EOF
-	test -S "$XDG_CACHE_HOME/git/credential/socket"
+	test_path_is_socket "$XDG_CACHE_HOME/git/credential/socket"
 '

 test_expect_success 'use user socket if user directory exists' '
@ -79,14 +94,15 @@ test_expect_success 'use user socket if user directory exists' '
 		git credential-cache exit &&
 		rmdir \"\$HOME/.git-credential-cache/\"
 	" &&
-	mkdir -p -m 700 "$HOME/.git-credential-cache/" &&
+	mkdir -p "$HOME/.git-credential-cache/" &&
+	chmod 700 "$HOME/.git-credential-cache/" &&
 	check approve cache <<-\EOF &&
 	protocol=https
 	host=example.com
 	username=store-user
 	password=store-pass
 	EOF
-	test -S "$HOME/.git-credential-cache/socket"
+	test_path_is_socket "$HOME/.git-credential-cache/socket"
 '

 test_expect_success SYMLINKS 'use user socket if user directory is a symlink to a directory' '
@ -103,7 +119,7 @@ test_expect_success SYMLINKS 'use user socket if user directory is a symlink to
 	username=store-user
 	password=store-pass
 	EOF
-	test -S "$HOME/.git-credential-cache/socket"
+	test_path_is_socket "$HOME/.git-credential-cache/socket"
 '

 helper_test_timeout cache --timeout=1
--- a/t/t1400-update-ref.sh
+++ b/t/t1400-update-ref.sh
@ -1598,6 +1598,40 @@ test_expect_success 'transaction cannot restart ongoing transaction' '
 	test_must_fail git show-ref --verify refs/heads/restart
 '

+test_expect_success PIPE 'transaction flushes status updates' '
+	mkfifo in out &&
+	(git update-ref --stdin <in >out &) &&
+
+	exec 9>in &&
+	exec 8<out &&
+	test_when_finished "exec 9>&-" &&
+	test_when_finished "exec 8<&-" &&
+
+	echo "start" >&9 &&
+	echo "start: ok" >expected &&
+	read line <&8 &&
+	echo "$line" >actual &&
+	test_cmp expected actual &&
+
+	echo "create refs/heads/flush $A" >&9 &&
+
+	echo prepare >&9 &&
+	echo "prepare: ok" >expected &&
+	read line <&8 &&
+	echo "$line" >actual &&
+	test_cmp expected actual &&
+
+	# This must now fail given that we have locked the ref.
+	test_must_fail git update-ref refs/heads/flush $B 2>stderr &&
+	grep "fatal: update_ref failed for ref ${SQ}refs/heads/flush${SQ}: cannot lock ref" stderr &&
+
+	echo commit >&9 &&
+	echo "commit: ok" >expected &&
+	read line <&8 &&
+	echo "$line" >actual &&
+	test_cmp expected actual
+'
+
 test_expect_success 'directory not created deleting packed ref' '
 	git branch d1/d2/r1 HEAD &&
 	git pack-refs --all &&
--- a/t/t1430-bad-ref-name.sh
+++ b/t/t1430-bad-ref-name.sh
@ -170,7 +170,7 @@ test_expect_success 'for-each-ref emits warnings for broken names' '
 	! grep -e "badname" output &&
 	! grep -e "broken\.\.\.symref" output &&
 	test_i18ngrep "ignoring ref with broken name refs/heads/broken\.\.\.ref" error &&
-	test_i18ngrep "ignoring broken ref refs/heads/badname" error &&
+	test_i18ngrep ! "ignoring broken ref refs/heads/badname" error &&
 	test_i18ngrep "ignoring ref with broken name refs/heads/broken\.\.\.symref" error
 '

--- a/t/t2021-checkout-overwrite.sh
+++ b/t/t2021-checkout-overwrite.sh
@ -48,6 +48,7 @@ test_expect_success 'checkout commit with dir must not remove untracked a/b' '

 test_expect_success SYMLINKS 'the symlink remained' '

+	test_when_finished "rm a/b" &&
 	test -h a/b
 '

--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@ -297,6 +297,7 @@ test_expect_success 'abort with error when new base cannot be checked out' '
 		output &&
 	test_i18ngrep "file1" output &&
 	test_path_is_missing .git/rebase-merge &&
+	rm file1 &&
 	git reset --hard HEAD^
 '

--- a/t/t3435-rebase-gpg-sign.sh
+++ b/t/t3435-rebase-gpg-sign.sh
@ -65,6 +65,7 @@ test_rebase_gpg_sign ! true  -i --gpg-sign --no-gpg-sign
 test_rebase_gpg_sign   false -i --no-gpg-sign --gpg-sign

 test_expect_failure 'rebase -p --no-gpg-sign override commit.gpgsign' '
+	test_when_finished "git clean -f" &&
 	git reset --hard merged &&
 	git config commit.gpgsign true &&
 	git rebase -p --no-gpg-sign --onto=one fork-point main &&
--- a/t/t3510-cherry-pick-sequence.sh
+++ b/t/t3510-cherry-pick-sequence.sh
@ -238,6 +238,7 @@ test_expect_success 'allow skipping commit but not abort for a new history' '
 '

 test_expect_success 'allow skipping stopped cherry-pick because of untracked file modifications' '
+	test_when_finished "rm unrelated" &&
 	pristine_detach initial &&
 	git rm --cached unrelated &&
 	git commit -m "untrack unrelated" &&
--- a/t/t4151-am-abort.sh
+++ b/t/t4151-am-abort.sh
@ -23,7 +23,13 @@ test_expect_success setup '
 		test_tick &&
 		git commit -a -m $i || return 1
 	done &&
+	git branch changes &&
 	git format-patch --no-numbered initial &&
+	git checkout -b conflicting initial &&
+	echo different >>file-1 &&
+	echo whatever >new-file &&
+	git add file-1 new-file &&
+	git commit -m different &&
 	git checkout -b side initial &&
 	echo local change >file-2-expect
 '
@ -191,4 +197,37 @@ test_expect_success 'am --abort leaves index stat info alone' '
 	git diff-files --exit-code --quiet
 '

+test_expect_success 'git am --abort return failed exit status when it fails' '
+	test_when_finished "rm -rf file-2/ && git reset --hard && git am --abort" &&
+	git checkout changes &&
+	git format-patch -1 --stdout conflicting >changes.mbox &&
+	test_must_fail git am --3way changes.mbox &&
+
+	git rm file-2 &&
+	mkdir file-2 &&
+	echo precious >file-2/somefile &&
+	test_must_fail git am --abort &&
+	test_path_is_dir file-2/
+'
+
+test_expect_success 'git am --abort cleans relevant files' '
+	git checkout changes &&
+	git format-patch -1 --stdout conflicting >changes.mbox &&
+	test_must_fail git am --3way changes.mbox &&
+
+	test_path_is_file new-file &&
+	echo further changes >>file-1 &&
+	echo change other file >>file-2 &&
+
+	# Abort, and expect the files touched by am to be reverted
+	git am --abort &&
+
+	test_path_is_missing new-file &&
+
+	# Files not involved in am operation are left modified
+	git diff --name-only changes >actual &&
+	test_write_lines file-2 >expect &&
+	test_cmp expect actual
+'
+
 test_done
--- a/t/t5304-prune.sh
+++ b/t/t5304-prune.sh
@ -291,6 +291,7 @@ test_expect_success 'prune: handle HEAD reflog in multiple worktrees' '
 		cat ../expected >blob &&
 		git add blob &&
 		git commit -m "second commit in third" &&
+		git clean -f && # Remove untracked left behind by deleting index
 		git reset --hard HEAD^
 	) &&
 	git prune --expire=now &&
--- a/t/t5312-prune-corruption.sh
+++ b/t/t5312-prune-corruption.sh
@ -7,6 +7,9 @@ if we see, for example, a ref with a bogus name, it is OK either to
 bail out or to proceed using it as a reachable tip, but it is _not_
 OK to proceed as if it did not exist. Otherwise we might silently
 delete objects that cannot be recovered.
+
+Note that we do assert command failure in these cases, because that is
+what currently happens. If that changes, these tests should be revisited.
 '
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
@ -18,39 +21,58 @@ test_expect_success 'disable reflogs' '
 	git reflog expire --expire=all --all
 '

+create_bogus_ref () {
+	test_when_finished 'rm -f .git/refs/heads/bogus..name' &&
+	echo $bogus >.git/refs/heads/bogus..name
+}
+
 test_expect_success 'create history reachable only from a bogus-named ref' '
 	test_tick && git commit --allow-empty -m main &&
 	base=$(git rev-parse HEAD) &&
 	test_tick && git commit --allow-empty -m bogus &&
 	bogus=$(git rev-parse HEAD) &&
 	git cat-file commit $bogus >saved &&
-	echo $bogus >.git/refs/heads/bogus..name &&
 	git reset --hard HEAD^
 '

 test_expect_success 'pruning does not drop bogus object' '
 	test_when_finished "git hash-object -w -t commit saved" &&
-	test_might_fail git prune --expire=now &&
-	verbose git cat-file -e $bogus
+	create_bogus_ref &&
+	test_must_fail git prune --expire=now &&
+	git cat-file -e $bogus
 '

 test_expect_success 'put bogus object into pack' '
 	git tag reachable $bogus &&
 	git repack -ad &&
 	git tag -d reachable &&
-	verbose git cat-file -e $bogus
+	git cat-file -e $bogus
 '

+test_expect_success 'non-destructive repack bails on bogus ref' '
+	create_bogus_ref &&
+	test_must_fail git repack -adk
+'
+
+test_expect_success 'GIT_REF_PARANOIA=0 overrides safety' '
+	create_bogus_ref &&
+	GIT_REF_PARANOIA=0 git repack -adk
+'
+
+
 test_expect_success 'destructive repack keeps packed object' '
-	test_might_fail git repack -Ad --unpack-unreachable=now &&
-	verbose git cat-file -e $bogus &&
-	test_might_fail git repack -ad &&
-	verbose git cat-file -e $bogus
+	create_bogus_ref &&
+	test_must_fail git repack -Ad --unpack-unreachable=now &&
+	git cat-file -e $bogus &&
+	test_must_fail git repack -ad &&
+	git cat-file -e $bogus
 '

-# subsequent tests will have different corruptions
-test_expect_success 'clean up bogus ref' '
-	rm .git/refs/heads/bogus..name
+test_expect_success 'destructive repack not confused by dangling symref' '
+	test_when_finished "git symbolic-ref -d refs/heads/dangling" &&
+	git symbolic-ref refs/heads/dangling refs/heads/does-not-exist &&
+	git repack -ad &&
+	test_must_fail git cat-file -e $bogus
 '

 # We create two new objects here, "one" and "two". Our
@ -77,8 +99,8 @@ test_expect_success 'create history with missing tip commit' '

 test_expect_success 'pruning with a corrupted tip does not drop history' '
 	test_when_finished "git hash-object -w -t commit saved" &&
-	test_might_fail git prune --expire=now &&
-	verbose git cat-file -e $recoverable
+	test_must_fail git prune --expire=now &&
+	git cat-file -e $recoverable
 '

 test_expect_success 'pack-refs does not silently delete broken loose ref' '
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@ -662,10 +662,10 @@ test_expect_success 'push does not update local refs on failure' '

 test_expect_success 'allow deleting an invalid remote ref' '

-	mk_test testrepo heads/main &&
+	mk_test testrepo heads/branch &&
 	rm -f testrepo/.git/objects/??/* &&
-	git push testrepo :refs/heads/main &&
-	(cd testrepo && test_must_fail git rev-parse --verify refs/heads/main)
+	git push testrepo :refs/heads/branch &&
+	(cd testrepo && test_must_fail git rev-parse --verify refs/heads/branch)

 '

@ -706,25 +706,26 @@ test_expect_success 'pushing valid refs triggers post-receive and post-update ho
 '

 test_expect_success 'deleting dangling ref triggers hooks with correct args' '
-	mk_test_with_hooks testrepo heads/main &&
+	mk_test_with_hooks testrepo heads/branch &&
+	orig=$(git -C testrepo rev-parse refs/heads/branch) &&
 	rm -f testrepo/.git/objects/??/* &&
-	git push testrepo :refs/heads/main &&
+	git push testrepo :refs/heads/branch &&
 	(
 		cd testrepo/.git &&
 		cat >pre-receive.expect <<-EOF &&
-		$ZERO_OID $ZERO_OID refs/heads/main
+		$orig $ZERO_OID refs/heads/branch
 		EOF

 		cat >update.expect <<-EOF &&
-		refs/heads/main $ZERO_OID $ZERO_OID
+		refs/heads/branch $orig $ZERO_OID
 		EOF

 		cat >post-receive.expect <<-EOF &&
-		$ZERO_OID $ZERO_OID refs/heads/main
+		$orig $ZERO_OID refs/heads/branch
 		EOF

 		cat >post-update.expect <<-EOF &&
-		refs/heads/main
+		refs/heads/branch
 		EOF

 		test_cmp pre-receive.expect pre-receive.actual &&
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@ -558,4 +558,13 @@ test_expect_success 'http auth forgets bogus credentials' '
 	expect_askpass both user@host
 '

+test_expect_success 'client falls back from v2 to v0 to match server' '
+	GIT_TRACE_PACKET=$PWD/trace \
+	GIT_TEST_PROTOCOL_VERSION=2 \
+	git clone $HTTPD_URL/smart_v0/repo.git repo-v0 &&
+	# check for v0; there the HEAD symref is communicated in the capability
+	# line; v2 uses a different syntax on each ref advertisement line
+	grep symref=HEAD:refs/heads/ trace
+'
+
 test_done
--- a/t/t5600-clone-fail-cleanup.sh
+++ b/t/t5600-clone-fail-cleanup.sh
@ -35,7 +35,9 @@ test_expect_success 'create a repo to clone' '
 '

 test_expect_success 'create objects in repo for later corruption' '
-	test_commit -C foo file
+	test_commit -C foo file &&
+	git -C foo checkout --detach &&
+	test_commit -C foo detached
 '

 # source repository given to git clone should be relative to the
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@ -962,4 +962,22 @@ test_expect_success 'bisect handles annotated tags' '
 	grep "$bad is the first bad commit" output
 '

+test_expect_success 'bisect run fails with exit code equals or greater than 128' '
+	write_script test_script.sh <<-\EOF &&
+	exit 128
+	EOF
+	test_must_fail git bisect run ./test_script.sh &&
+	write_script test_script.sh <<-\EOF &&
+	exit 255
+	EOF
+	test_must_fail git bisect run ./test_script.sh
+'
+
+test_expect_success 'bisect visualize with a filename with dash and space' '
+	echo "My test line" >>"./-hello 2" &&
+	git add -- "./-hello 2" &&
+	git commit --quiet -m "Add test line" -- "./-hello 2" &&
+	git bisect visualize -p -- "-hello 2"
+'
+
 test_done
--- a/t/t6415-merge-dir-to-symlink.sh
+++ b/t/t6415-merge-dir-to-symlink.sh
@ -25,7 +25,8 @@ test_expect_success 'checkout does not clobber untracked symlink' '
 	git reset --hard main &&
 	git rm --cached a/b &&
 	git commit -m "untracked symlink remains" &&
-	test_must_fail git checkout start^0
+	test_must_fail git checkout start^0 &&
+	git clean -fd    # Do not leave the untracked symlink in the way
 '

 test_expect_success 'a/b-2/c/d is kept when clobbering symlink b' '
@ -34,7 +35,8 @@ test_expect_success 'a/b-2/c/d is kept when clobbering symlink b' '
 	git rm --cached a/b &&
 	git commit -m "untracked symlink remains" &&
 	git checkout -f start^0 &&
-	test_path_is_file a/b-2/c/d
+	test_path_is_file a/b-2/c/d &&
+	git clean -fd    # Do not leave the untracked symlink in the way
 '

 test_expect_success 'checkout should not have deleted a/b-2/c/d' '
--- a/t/t6424-merge-unrelated-index-changes.sh
+++ b/t/t6424-merge-unrelated-index-changes.sh
@ -132,6 +132,7 @@ test_expect_success 'merge-recursive, when index==head but head!=HEAD' '

 	# Make index match B
 	git diff C B -- | git apply --cached &&
+	test_when_finished "git clean -fd" &&  # Do not leave untracked around
 	# Merge B & F, with B as "head"
 	git merge-recursive A -- B F > out &&
 	test_i18ngrep "Already up to date" out
--- a/t/t6430-merge-recursive.sh
+++ b/t/t6430-merge-recursive.sh
@ -718,7 +718,9 @@ test_expect_success 'merge-recursive remembers the names of all base trees' '
 	# merge-recursive prints in reverse order, but we do not care
 	sort <trees >expect &&
 	sed -n "s/^virtual //p" out | sort >actual &&
-	test_cmp expect actual
+	test_cmp expect actual &&
+
+	git clean -fd
 '

 test_expect_success 'merge-recursive internal merge resolves to the sameness' '
--- a/t/t6436-merge-overwrite.sh
+++ b/t/t6436-merge-overwrite.sh
@ -68,7 +68,8 @@ test_expect_success 'will not overwrite removed file' '
 	git commit -m "rm c1.c" &&
 	cp important c1.c &&
 	test_must_fail git merge c1a &&
-	test_cmp important c1.c
+	test_cmp important c1.c &&
+	rm c1.c  # Do not leave untracked file in way of future tests
 '

 test_expect_success 'will not overwrite re-added file' '
--- a/t/t7201-co.sh
+++ b/t/t7201-co.sh
@ -585,6 +585,7 @@ test_expect_success 'checkout --conflict=diff3' '
 '

 test_expect_success 'failing checkout -b should not break working tree' '
+	git clean -fd &&  # Remove untracked files in the way
 	git reset --hard main &&
 	git symbolic-ref HEAD refs/heads/main &&
 	test_must_fail git checkout -b renamer side^ &&
--- a/t/t7600-merge.sh
+++ b/t/t7600-merge.sh
@ -717,6 +717,7 @@ test_expect_success 'failed fast-forward merge with --autostash' '
 	git reset --hard c0 &&
 	git merge-file file file.orig file.5 &&
 	cp file.5 other &&
+	test_when_finished "rm other" &&
 	test_must_fail git merge --autostash c1 2>err &&
 	test_i18ngrep "Applied autostash." err &&
 	test_cmp file.5 file
--- a/t/t7900-maintenance.sh
+++ b/t/t7900-maintenance.sh
@ -277,7 +277,7 @@ test_expect_success 'incremental-repack task' '

 	# Delete refs that have not been repacked in these packs.
 	git for-each-ref --format="delete %(refname)" \
-		refs/prefetch refs/tags >refs &&
+		refs/prefetch refs/tags refs/remotes >refs &&
 	git update-ref --stdin <refs &&

 	# Replace the object directory with this pack layout.
@ -286,6 +286,10 @@ test_expect_success 'incremental-repack task' '
 	ls $packDir/*.pack >packs-before &&
 	test_line_count = 3 packs-before &&

+	# make sure we do not have any broken refs that were
+	# missed in the deletion above
+	git for-each-ref &&
+
 	# the job repacks the two into a new pack, but does not
 	# delete the old ones.
 	git maintenance run --task=incremental-repack &&
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@ -534,7 +534,7 @@ SQ=\'
 # when case-folding filenames
 u200c=$(printf '\342\200\214')

-export _x05 _x35 _x40 _z40 LF u200c EMPTY_TREE EMPTY_BLOB ZERO_OID OID_REGEX
+export _x05 _x35 LF u200c EMPTY_TREE EMPTY_BLOB ZERO_OID OID_REGEX

 # Each test should start with something like this, after copyright notices:
 #
@ -1425,10 +1425,9 @@ then
 fi

 # Convenience
-# A regexp to match 5, 35 and 40 hexdigits
+# A regexp to match 5 and 35 hexdigits
 _x05='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
 _x35="$_x05$_x05$_x05$_x05$_x05$_x05$_x05"
-_x40="$_x35$_x05"

 test_oid_init

@ -1437,7 +1436,6 @@ OID_REGEX=$(echo $ZERO_OID | sed -e 's/0/[0-9a-f]/g')
 OIDPATH_REGEX=$(test_oid_to_path $ZERO_OID | sed -e 's/0/[0-9a-f]/g')
 EMPTY_TREE=$(test_oid empty_tree)
 EMPTY_BLOB=$(test_oid empty_blob)
-_z40=$ZERO_OID

 # Provide an implementation of the 'yes' utility; the upper bound
 # limit is there to help Windows that cannot stop this loop from
--- a/tree-diff.c
+++ b/tree-diff.c
@ -21,7 +21,9 @@
 		ALLOC_ARRAY((x), nr); \
 } while(0)
 #define FAST_ARRAY_FREE(x, nr) do { \
-	if ((nr) > 2) \
+	if ((nr) <= 2) \
+		xalloca_free((x)); \
+	else \
 		free((x)); \
 } while(0)