Merge branch 'sj/t9117-path-is-file' GSoC practice to replace "test -f" with "test_path_is_file". * sj/t9117-path-is-file: t9117: prefer test_path_* helper functions

diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines
index a6a9656..32e69f7 100644
--- a/Documentation/CodingGuidelines
+++ b/Documentation/CodingGuidelines

@@ -446,12 +446,41 @@
    detail.
 
  - The first #include in C files, except in platform specific compat/
-   implementations and sha1dc/, must be either "git-compat-util.h" or
-   one of the approved headers that includes it first for you.  (The
-   approved headers currently include "builtin.h",
-   "t/helper/test-tool.h", "xdiff/xinclude.h", or
-   "reftable/system.h".)  You do not have to include more than one of
-   these.
+   implementations and sha1dc/, must be <git-compat-util.h>.  This
+   header file insulates other header files and source files from
+   platform differences, like which system header files must be
+   included in what order, and what C preprocessor feature macros must
+   be defined to trigger certain features we expect out of the system.
+   A collorary to this is that C files should not directly include
+   system header files themselves.
+
+   There are some exceptions, because certain group of files that
+   implement an API all have to include the same header file that
+   defines the API and it is convenient to include <git-compat-util.h>
+   there.  Namely:
+
+   - the implementation of the built-in commands in the "builtin/"
+     directory that include "builtin.h" for the cmd_foo() prototype
+     definition,
+
+   - the test helper programs in the "t/helper/" directory that include
+     "t/helper/test-tool.h" for the cmd__foo() prototype definition,
+
+   - the xdiff implementation in the "xdiff/" directory that includes
+     "xdiff/xinclude.h" for the xdiff machinery internals,
+
+   - the unit test programs in "t/unit-tests/" directory that include
+     "t/unit-tests/test-lib.h" that gives them the unit-tests
+     framework, and
+
+   - the source files that implement reftable in the "reftable/"
+     directory that include "reftable/system.h" for the reftable
+     internals,
+
+   are allowed to assume that they do not have to include
+   <git-compat-util.h> themselves, as it is included as the first
+   '#include' in these header files.  These headers must be the first
+   header file to be "#include"d in them, though.
 
  - A C file must directly include the header files that declare the
    functions and the types it uses, except for the functions and types

diff --git a/Documentation/RelNotes/2.45.0.txt b/Documentation/RelNotes/2.45.0.txt
index 321da04..c0f9b9e 100644
--- a/Documentation/RelNotes/2.45.0.txt
+++ b/Documentation/RelNotes/2.45.0.txt

@@ -17,6 +17,23 @@
 
  * "git reflog" learned a "list" subcommand that enumerates known reflogs.
 
+ * When a merge conflicted at a submodule, merge-ort backend used to
+   unconditionally give a lengthy message to suggest how to resolve
+   it.  Now the message can be squelched as an advice message.
+
+ * "git for-each-ref" learned "--include-root-refs" option to show
+   even the stuff outside the 'refs/' hierarchy.
+
+ * "git rev-list --missing=print" has learned to optionally take
+   "--allow-missing-tips", which allows the objects at the starting
+   points to be missing.
+
+ * "git merge-tree" has learned that the three trees involved in the
+   3-way merge only need to be trees, not necessarily commits.
+
+ * "git log --merge" learned to pay attention to CHERRY_PICK_HEAD and
+   other kinds of *_HEAD pseudorefs.
+
 
 Performance, Internal Implementation, Development Support etc.
 
@@ -33,6 +50,10 @@
    specified; use "_<placeholder>_" to typeset the word inside a pair
    of <angle-brakets> emphasized.
 
+ * "git --no-lazy-fetch cmd" allows to run "cmd" while disabling lazy
+   fetching of objects from the promisor remote, which may be handy
+   for debugging.
+
 
 Fixes since v2.44
 -----------------
@@ -65,6 +86,47 @@
    option; it used to always exit with 0 and signalled success.
    (merge eb84c8b6ce ps/difftool-dir-diff-exit-code later to maint).
 
+ * The code incorrectly attempted to use textconv cache when asked,
+   even when we are not running in a repository, which has been
+   corrected.
+   (merge affe355fe7 jk/textconv-cache-outside-repo-fix later to maint).
+
+ * Remove an empty file that shouldn't have been added in the first
+   place.
+   (merge 4f66942215 js/remove-cruft-files later to maint).
+
+ * The logic to access reflog entries by date and number had ugly
+   corner cases at the boundaries, which have been cleaned up.
+   (merge 5edd126720 jk/reflog-special-cases-fix later to maint).
+
+ * An error message from "git upload-pack", which responds to "git
+   fetch" requests, had a trialing NUL in it, which has been
+   corrected.
+   (merge 3f4c7a0805 sg/upload-pack-error-message-fix later to maint).
+
+ * Clarify wording in the CodingGuidelines that requires <git-compat-util.h>
+   to be the first header file.
+   (merge 4e89f0e07c jc/doc-compat-util later to maint).
+
+ * "git commit -v --cleanup=scissors" used to add the scissors line
+   twice in the log message buffer, which has been corrected.
+   (merge e90cc075cc jt/commit-redundant-scissors-fix later to maint).
+
+ * A custom remote helper no longer cannot access the newly created
+   repository during "git clone", which is a regression in Git 2.44.
+   This has been corrected.
+   (merge 199f44cb2e ps/remote-helper-repo-initialization-fix later to maint).
+
+ * Various parts of upload-pack has been updated to bound the resource
+   consumption relative to the size of the repository to protect from
+   abusive clients.
+   (merge 6cd05e768b jk/upload-pack-bounded-resources later to maint).
+
+ * The upload-pack program, when talking over v2, accepted the
+   packfile-uris protocol extension from the client, even if it did
+   not advertise the capability, which has been corrected.
+   (merge a922bfa3b5 jk/upload-pack-v2-capability-cleanup later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge f0e578c69c rs/use-xstrncmpz later to maint).
    (merge 83e6eb7d7a ba/credential-test-clean-fix later to maint).
@@ -74,3 +136,9 @@
    (merge 41bff66e35 jc/doc-add-placeholder-fix later to maint).
    (merge 6835f0efe9 jw/remote-doc-typofix later to maint).
    (merge 244001aa20 hs/rebase-not-in-progress later to maint).
+   (merge 2ca6c07db2 jc/no-include-of-compat-util-from-headers later to maint).
+   (merge 87bd7fbb9c rs/fetch-simplify-with-starts-with later to maint).
+   (merge f39addd0d9 rs/name-rev-with-mempool later to maint).
+   (merge 9a97b43e03 rs/submodule-prefix-simplify later to maint).
+   (merge 40b8076462 ak/rebase-autosquash later to maint).
+   (merge 3223204456 eg/add-uflags later to maint).

diff --git a/Documentation/config.txt b/Documentation/config.txt
index e3a74dd..782c2ba 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt

@@ -369,20 +369,18 @@
 names do not conflict with those that are used by Git itself and
 other popular tools, and describe them in your documentation.
 
-include::config/advice.txt[]
-
-include::config/attr.txt[]
-
-include::config/core.txt[]
-
 include::config/add.txt[]
 
+include::config/advice.txt[]
+
 include::config/alias.txt[]
 
 include::config/am.txt[]
 
 include::config/apply.txt[]
 
+include::config/attr.txt[]
+
 include::config/blame.txt[]
 
 include::config/branch.txt[]
@@ -405,10 +403,12 @@
 
 include::config/commitgraph.txt[]
 
-include::config/credential.txt[]
-
 include::config/completion.txt[]
 
+include::config/core.txt[]
+
+include::config/credential.txt[]
+
 include::config/diff.txt[]
 
 include::config/difftool.txt[]
@@ -421,10 +421,10 @@
 
 include::config/fetch.txt[]
 
-include::config/format.txt[]
-
 include::config/filter.txt[]
 
+include::config/format.txt[]
+
 include::config/fsck.txt[]
 
 include::config/fsmonitor--daemon.txt[]
@@ -435,10 +435,10 @@
 
 include::config/gitweb.txt[]
 
-include::config/grep.txt[]
-
 include::config/gpg.txt[]
 
+include::config/grep.txt[]
+
 include::config/gui.txt[]
 
 include::config/guitool.txt[]
@@ -519,10 +519,10 @@
 
 include::config/ssh.txt[]
 
-include::config/status.txt[]
-
 include::config/stash.txt[]
 
+include::config/status.txt[]
+
 include::config/submodule.txt[]
 
 include::config/tag.txt[]

diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index c7ea70f..dde8e78 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt

@@ -129,6 +129,9 @@
 	submoduleAlternateErrorStrategyDie::
 		Advice shown when a submodule.alternateErrorStrategy option
 		configured to "die" causes a fatal error.
+	submoduleMergeConflict::
+		Advice shown when a non-trivial submodule merge conflict is
+		encountered.
 	submodulesNotUpdated::
 		Advice shown when a user runs a submodule command that fails
 		because `git submodule update --init` was not run.

diff --git a/Documentation/config/transfer.txt b/Documentation/config/transfer.txt
index a9cbdb8..f1ce50f 100644
--- a/Documentation/config/transfer.txt
+++ b/Documentation/config/transfer.txt

@@ -121,3 +121,7 @@
 	information from the remote server (if advertised) and download
 	bundles before continuing the clone through the Git protocol.
 	Defaults to `false`.
+
+transfer.advertiseObjectInfo::
+	When `true`, the `object-info` capability is advertised by
+	servers. Defaults to false.

diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index 3a9ad91..c1dd12b 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt

@@ -10,7 +10,7 @@
 [verse]
 'git for-each-ref' [--count=<count>] [--shell|--perl|--python|--tcl]
 		   [(--sort=<key>)...] [--format=<format>]
-		   [ --stdin | <pattern>... ]
+		   [--include-root-refs] [ --stdin | <pattern>... ]
 		   [--points-at=<object>]
 		   [--merged[=<object>]] [--no-merged[=<object>]]
 		   [--contains[=<object>]] [--no-contains[=<object>]]
@@ -105,6 +105,9 @@
 	any excluded pattern(s) are shown. Matching is done using the
 	same rules as `<pattern>` above.
 
+--include-root-refs::
+	List root refs (HEAD and pseudorefs) apart from regular refs.
+
 FIELD NAMES
 -----------
 

diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt
index b50acac..dd388fa 100644
--- a/Documentation/git-merge-tree.txt
+++ b/Documentation/git-merge-tree.txt

@@ -64,10 +64,13 @@
 	share no common history.  This flag can be given to override that
 	check and make the merge proceed anyway.
 
---merge-base=<commit>::
+--merge-base=<tree-ish>::
 	Instead of finding the merge-bases for <branch1> and <branch2>,
 	specify a merge-base for the merge, and specifying multiple bases is
 	currently not supported. This option is incompatible with `--stdin`.
++
+As the merge-base is provided directly, <branch1> and <branch2> do not need
+to specify commits; trees are enough.
 
 [[OUTPUT]]
 OUTPUT

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 0620652..e7e7250 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt

@@ -607,7 +607,7 @@
 linkgit:git-commit[1], which take the target commit as an argument and
 automatically fill in the subject line of the new commit from that.
 +
-Settting configuration variable `rebase.autoSquash` to true enables
+Setting configuration variable `rebase.autoSquash` to true enables
 auto-squashing by default for interactive rebase.  The `--no-autosquash`
 option can be used to override that setting.
 +

diff --git a/Documentation/git.txt b/Documentation/git.txt
index 0d25224..e6b766d 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt

@@ -174,8 +174,17 @@
 	directory.
 
 --no-replace-objects::
-	Do not use replacement refs to replace Git objects. See
-	linkgit:git-replace[1] for more information.
+	Do not use replacement refs to replace Git objects.
+	This is equivalent to exporting the `GIT_NO_REPLACE_OBJECTS`
+	environment variable with any value.
+	See linkgit:git-replace[1] for more information.
+
+--no-lazy-fetch::
+	Do not fetch missing objects from the promisor remote on
+	demand.  Useful together with `git cat-file -e <object>` to
+	see if the object is locally available.
+	This is equivalent to setting the `GIT_NO_LAZY_FETCH`
+	environment variable to `1`.
 
 --literal-pathspecs::
 	Treat pathspecs literally (i.e. no globbing, no pathspec magic).
@@ -872,6 +881,10 @@
 	header and packfile URIs. Set this Boolean environment variable to false to prevent this
 	redaction.
 
+`GIT_NO_REPLACE_OBJECTS`::
+	Setting and exporting this environment variable tells Git to
+	ignore replacement refs and do not replace Git objects.
+
 `GIT_LITERAL_PATHSPECS`::
 	Setting this Boolean environment variable to true will cause Git to treat all
 	pathspecs literally, rather than as glob patterns. For example,
@@ -893,6 +906,11 @@
 	Setting this Boolean environment variable to true will cause Git to treat all
 	pathspecs as case-insensitive.
 
+`GIT_NO_LAZY_FETCH`::
+	Setting this Boolean environment variable to true tells Git
+	not to lazily fetch missing objects from the promisor remote
+	on demand.
+
 `GIT_REFLOG_ACTION`::
 	When a ref is updated, reflog entries are created to keep
 	track of the reason why the ref was updated (which is

diff --git a/Documentation/gitcli.txt b/Documentation/gitcli.txt
index e5fac94..7c70932 100644
--- a/Documentation/gitcli.txt
+++ b/Documentation/gitcli.txt

@@ -81,9 +81,6 @@
 Here are the rules regarding the "flags" that you should follow when you are
 scripting Git:
 
- * It's preferred to use the non-dashed form of Git commands, which means that
-   you should prefer `git foo` to `git-foo`.
-
  * Splitting short options to separate words (prefer `git foo -a -b`
    to `git foo -ab`, the latter may not even work).
 

diff --git a/Documentation/gitprotocol-v2.txt b/Documentation/gitprotocol-v2.txt
index 0b800ab..414bc62 100644
--- a/Documentation/gitprotocol-v2.txt
+++ b/Documentation/gitprotocol-v2.txt

@@ -346,7 +346,8 @@
     want-ref <ref>
 	Indicates to the server that the client wants to retrieve a
 	particular ref, where <ref> is the full name of a ref on the
-	server.
+	server.  It is a protocol error to send want-ref for the
+	same ref more than once.
 
 If the 'sideband-all' feature is advertised, the following argument can be
 included in the client's request:
@@ -361,7 +362,8 @@
 If the 'packfile-uris' feature is advertised, the following argument
 can be included in the client's request as well as the potential
 addition of the 'packfile-uris' section in the server's response as
-explained below.
+explained below. Note that at most one `packfile-uris` line can be sent
+to the server.
 
     packfile-uris <comma-separated-list-of-protocols>
 	Indicates to the server that the client is willing to receive

diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index a583b52..408d931 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt

@@ -341,8 +341,11 @@
 Under `--pretty=reference`, this information will not be shown at all.
 
 --merge::
-	After a failed merge, show refs that touch files having a
-	conflict and don't exist on all heads to merge.
+	Show commits touching conflicted paths in the range `HEAD...<other>`,
+	where `<other>` is the first existing pseudoref in `MERGE_HEAD`,
+	`CHERRY_PICK_HEAD`, `REVERT_HEAD` or `REBASE_HEAD`. Only works
+	when the index has unmerged entries. This option can be used to show
+	relevant commits when resolving conflicts from a 3-way merge.
 
 --boundary::
 	Output excluded boundary commits. Boundary commits are
@@ -1019,6 +1022,10 @@
 +
 The form '--missing=print' is like 'allow-any', but will also print a
 list of the missing objects.  Object IDs are prefixed with a ``?'' character.
++
+If some tips passed to the traversal are missing, they will be
+considered as missing too, and the traversal will ignore them. In case
+we cannot get their Object ID though, an error will be raised.
 
 --exclude-promisor-objects::
 	(For internal use only.)  Prefilter object traversal at

diff --git a/GIT-VERSION-GEN b/GIT-VERSION-GEN
index c9d1d29..df788c7 100755
--- a/GIT-VERSION-GEN
+++ b/GIT-VERSION-GEN

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 GVF=GIT-VERSION-FILE
-DEF_VER=v2.44.0
+DEF_VER=v2.44.GIT
 
 LF='
 '

diff --git a/advice.c b/advice.c
index 6e9098f..4ba64ee 100644
--- a/advice.c
+++ b/advice.c

@@ -79,6 +79,7 @@ static struct {
 	[ADVICE_STATUS_U_OPTION]			= { "statusUoption" },
 	[ADVICE_SUBMODULES_NOT_UPDATED] 		= { "submodulesNotUpdated" },
 	[ADVICE_SUBMODULE_ALTERNATE_ERROR_STRATEGY_DIE] = { "submoduleAlternateErrorStrategyDie" },
+	[ADVICE_SUBMODULE_MERGE_CONFLICT]               = { "submoduleMergeConflict" },
 	[ADVICE_SUGGEST_DETACHING_HEAD]			= { "suggestDetachingHead" },
 	[ADVICE_UPDATE_SPARSE_PATH]			= { "updateSparsePath" },
 	[ADVICE_WAITING_FOR_EDITOR]			= { "waitingForEditor" },

diff --git a/advice.h b/advice.h
index 9d4f49a..7d0a821 100644
--- a/advice.h
+++ b/advice.h

@@ -47,6 +47,7 @@ enum advice_type {
 	ADVICE_STATUS_U_OPTION,
 	ADVICE_SUBMODULES_NOT_UPDATED,
 	ADVICE_SUBMODULE_ALTERNATE_ERROR_STRATEGY_DIE,
+	ADVICE_SUBMODULE_MERGE_CONFLICT,
 	ADVICE_SUGGEST_DETACHING_HEAD,
 	ADVICE_UPDATE_SPARSE_PATH,
 	ADVICE_WAITING_FOR_EDITOR,

diff --git a/bisect.c b/bisect.c
index f75e50c..60aae2f 100644
--- a/bisect.c
+++ b/bisect.c

@@ -836,10 +836,11 @@ static void handle_skipped_merge_base(const struct object_id *mb)
 static enum bisect_error check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
 {
 	enum bisect_error res = BISECT_OK;
-	struct commit_list *result;
+	struct commit_list *result = NULL;
 
-	result = repo_get_merge_bases_many(the_repository, rev[0], rev_nr - 1,
-					   rev + 1);
+	if (repo_get_merge_bases_many(the_repository, rev[0], rev_nr - 1,
+				      rev + 1, &result) < 0)
+		exit(128);
 
 	for (; result; result = result->next) {
 		const struct object_id *mb = &result->item->object.oid;

diff --git a/builtin/add.c b/builtin/add.c
index ada7719..393c10c 100644
--- a/builtin/add.c
+++ b/builtin/add.c

@@ -115,7 +115,7 @@ static int refresh(int verbose, const struct pathspec *pathspec)
 	int i, ret = 0;
 	char *skip_worktree_seen = NULL;
 	struct string_list only_match_skip_worktree = STRING_LIST_INIT_NODUP;
-	int flags = REFRESH_IGNORE_SKIP_WORKTREE |
+	unsigned int flags = REFRESH_IGNORE_SKIP_WORKTREE |
 		    (verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET);
 
 	seen = xcalloc(pathspec->nr, 1);

diff --git a/builtin/branch.c b/builtin/branch.c
index cfb63cc..b3cbb7f 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c

@@ -158,6 +158,8 @@ static int branch_merged(int kind, const char *name,
 
 	merged = reference_rev ? repo_in_merge_bases(the_repository, rev,
 						     reference_rev) : 0;
+	if (merged < 0)
+		exit(128);
 
 	/*
 	 * After the safety valve is fully redefined to "check with
@@ -166,9 +168,13 @@ static int branch_merged(int kind, const char *name,
 	 * any of the following code, but during the transition period,
 	 * a gentle reminder is in order.
 	 */
-	if ((head_rev != reference_rev) &&
-	    (head_rev ? repo_in_merge_bases(the_repository, rev, head_rev) : 0) != merged) {
-		if (merged)
+	if (head_rev != reference_rev) {
+		int expect = head_rev ? repo_in_merge_bases(the_repository, rev, head_rev) : 0;
+		if (expect < 0)
+			exit(128);
+		if (expect == merged)
+			; /* okay */
+		else if (merged)
 			warning(_("deleting branch '%s' that has been merged to\n"
 				"         '%s', but not yet merged to HEAD"),
 				name, reference_name);

diff --git a/builtin/checkout.c b/builtin/checkout.c
index 067c251..15293a3 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c

@@ -704,7 +704,8 @@ static int reset_tree(struct tree *tree, const struct checkout_opts *o,
 	init_checkout_metadata(&opts.meta, info->refname,
 			       info->commit ? &info->commit->object.oid : null_oid(),
 			       NULL);
-	parse_tree(tree);
+	if (parse_tree(tree) < 0)
+		return 128;
 	init_tree_desc(&tree_desc, tree->buffer, tree->size);
 	switch (unpack_trees(1, &tree_desc, &opts)) {
 	case -2:
@@ -783,9 +784,15 @@ static int merge_working_tree(const struct checkout_opts *opts,
 		if (new_branch_info->commit)
 			BUG("'switch --orphan' should never accept a commit as starting point");
 		new_tree = parse_tree_indirect(the_hash_algo->empty_tree);
-	} else
+		if (!new_tree)
+			BUG("unable to read empty tree");
+	} else {
 		new_tree = repo_get_commit_tree(the_repository,
 						new_branch_info->commit);
+		if (!new_tree)
+			return error(_("unable to read tree (%s)"),
+				     oid_to_hex(&new_branch_info->commit->object.oid));
+	}
 	if (opts->discard_changes) {
 		ret = reset_tree(new_tree, opts, 1, writeout_error, new_branch_info);
 		if (ret)
@@ -820,7 +827,8 @@ static int merge_working_tree(const struct checkout_opts *opts,
 				oid_to_hex(old_commit_oid));
 
 		init_tree_desc(&trees[0], tree->buffer, tree->size);
-		parse_tree(new_tree);
+		if (parse_tree(new_tree) < 0)
+			exit(128);
 		tree = new_tree;
 		init_tree_desc(&trees[1], tree->buffer, tree->size);
 
@@ -1240,10 +1248,15 @@ static void setup_new_branch_info_and_source_tree(
 	if (!new_branch_info->commit) {
 		/* not a commit */
 		*source_tree = parse_tree_indirect(rev);
+		if (!*source_tree)
+			die(_("unable to read tree (%s)"), oid_to_hex(rev));
 	} else {
 		parse_commit_or_die(new_branch_info->commit);
 		*source_tree = repo_get_commit_tree(the_repository,
 						    new_branch_info->commit);
+		if (!*source_tree)
+			die(_("unable to read tree (%s)"),
+			    oid_to_hex(&new_branch_info->commit->object.oid));
 	}
 }
 

diff --git a/builtin/clone.c b/builtin/clone.c
index bad1b70..93892ab 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c

@@ -738,7 +738,8 @@ static int checkout(int submodule_progress, int filter_submodules)
 	tree = parse_tree_indirect(&oid);
 	if (!tree)
 		die(_("unable to parse commit %s"), oid_to_hex(&oid));
-	parse_tree(tree);
+	if (parse_tree(tree) < 0)
+		exit(128);
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts) < 0)
 		die(_("unable to checkout working tree"));
@@ -926,6 +927,7 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	struct ref *mapped_refs = NULL;
 	const struct ref *ref;
 	struct strbuf key = STRBUF_INIT;
+	struct strbuf buf = STRBUF_INIT;
 	struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 	struct transport *transport = NULL;
 	const char *src_ref_prefix = "refs/heads/";
@@ -1126,6 +1128,50 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	}
 
 	/*
+	 * We have a chicken-and-egg situation between initializing the refdb
+	 * and spawning transport helpers:
+	 *
+	 *   - Initializing the refdb requires us to know about the object
+	 *     format. We thus have to spawn the transport helper to learn
+	 *     about it.
+	 *
+	 *   - The transport helper may want to access the Git repository. But
+	 *     because the refdb has not been initialized, we don't have "HEAD"
+	 *     or "refs/". Thus, the helper cannot find the Git repository.
+	 *
+	 * Ideally, we would have structured the helper protocol such that it's
+	 * mandatory for the helper to first announce its capabilities without
+	 * yet assuming a fully initialized repository. Like that, we could
+	 * have added a "lazy-refdb-init" capability that announces whether the
+	 * helper is ready to handle not-yet-initialized refdbs. If any helper
+	 * didn't support them, we would have fully initialized the refdb with
+	 * the SHA1 object format, but later on bailed out if we found out that
+	 * the remote repository used a different object format.
+	 *
+	 * But we didn't, and thus we use the following workaround to partially
+	 * initialize the repository's refdb such that it can be discovered by
+	 * Git commands. To do so, we:
+	 *
+	 *   - Create an invalid HEAD ref pointing at "refs/heads/.invalid".
+	 *
+	 *   - Create the "refs/" directory.
+	 *
+	 *   - Set up the ref storage format and repository version as
+	 *     required.
+	 *
+	 * This is sufficient for Git commands to discover the Git directory.
+	 */
+	initialize_repository_version(GIT_HASH_UNKNOWN,
+				      the_repository->ref_storage_format, 1);
+
+	strbuf_addf(&buf, "%s/HEAD", git_dir);
+	write_file(buf.buf, "ref: refs/heads/.invalid");
+
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "%s/refs", git_dir);
+	safe_create_dir(buf.buf, 1);
+
+	/*
 	 * additional config can be injected with -c, make sure it's included
 	 * after init_db, which clears the entire config environment.
 	 */
@@ -1453,6 +1499,7 @@ int cmd_clone(int argc, const char **argv, const char *prefix)
 	free(remote_name);
 	strbuf_release(&reflog_msg);
 	strbuf_release(&branch_top);
+	strbuf_release(&buf);
 	strbuf_release(&key);
 	free_refs(mapped_refs);
 	free_refs(remote_head_points_at);

diff --git a/builtin/commit.c b/builtin/commit.c
index 6d1fa71..a911972 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c

@@ -331,7 +331,8 @@ static void create_base_index(const struct commit *current_head)
 	tree = parse_tree_indirect(&current_head->object.oid);
 	if (!tree)
 		die(_("failed to unpack HEAD tree object"));
-	parse_tree(tree);
+	if (parse_tree(tree) < 0)
+		exit(128);
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts))
 		exit(128); /* We've already reported the error, finish dying */
@@ -737,7 +738,6 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	const char *hook_arg2 = NULL;
 	int clean_message_contents = (cleanup_mode != COMMIT_MSG_CLEANUP_NONE);
 	int old_display_comment_prefix;
-	int merge_contains_scissors = 0;
 	int invoked_hook;
 
 	/* This checks and barfs if author is badly specified */
@@ -841,7 +841,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		    wt_status_locate_end(sb.buf + merge_msg_start,
 					 sb.len - merge_msg_start) <
 				sb.len - merge_msg_start)
-			merge_contains_scissors = 1;
+			s->added_cut_line = 1;
 	} else if (!stat(git_path_squash_msg(the_repository), &statbuf)) {
 		if (strbuf_read_file(&sb, git_path_squash_msg(the_repository), 0) < 0)
 			die_errno(_("could not read SQUASH_MSG"));
@@ -924,9 +924,8 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 			  " yourself if you want to.\n"
 			  "An empty message aborts the commit.\n");
 		if (whence != FROM_COMMIT) {
-			if (cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS &&
-				!merge_contains_scissors)
-				wt_status_add_cut_line(s->fp);
+			if (cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS)
+				wt_status_add_cut_line(s);
 			status_printf_ln(
 				s, GIT_COLOR_NORMAL,
 				whence == FROM_MERGE ?
@@ -946,8 +945,8 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		if (cleanup_mode == COMMIT_MSG_CLEANUP_ALL)
 			status_printf(s, GIT_COLOR_NORMAL, hint_cleanup_all, comment_line_char);
 		else if (cleanup_mode == COMMIT_MSG_CLEANUP_SCISSORS) {
-			if (whence == FROM_COMMIT && !merge_contains_scissors)
-				wt_status_add_cut_line(s->fp);
+			if (whence == FROM_COMMIT)
+				wt_status_add_cut_line(s);
 		} else /* COMMIT_MSG_CLEANUP_SPACE, that is. */
 			status_printf(s, GIT_COLOR_NORMAL, hint_cleanup_space, comment_line_char);
 

diff --git a/builtin/fast-import.c b/builtin/fast-import.c
index 92eda20..71a195c 100644
--- a/builtin/fast-import.c
+++ b/builtin/fast-import.c

@@ -1625,6 +1625,7 @@ static int update_branch(struct branch *b)
 		oidclr(&old_oid);
 	if (!force_update && !is_null_oid(&old_oid)) {
 		struct commit *old_cmit, *new_cmit;
+		int ret;
 
 		old_cmit = lookup_commit_reference_gently(the_repository,
 							  &old_oid, 0);
@@ -1633,7 +1634,10 @@ static int update_branch(struct branch *b)
 		if (!old_cmit || !new_cmit)
 			return error("Branch %s is missing commits.", b->name);
 
-		if (!repo_in_merge_bases(the_repository, old_cmit, new_cmit)) {
+		ret = repo_in_merge_bases(the_repository, old_cmit, new_cmit);
+		if (ret < 0)
+			exit(128);
+		if (!ret) {
 			warning("Not updating %s"
 				" (new tip %s does not contain %s)",
 				b->name, oid_to_hex(&b->oid),

diff --git a/builtin/fetch.c b/builtin/fetch.c
index 3aedfd1..46a7934 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c

@@ -448,9 +448,8 @@ static void filter_prefetch_refspec(struct refspec *rs)
 			continue;
 		if (!rs->items[i].dst ||
 		    (rs->items[i].src &&
-		     !strncmp(rs->items[i].src,
-			      ref_namespace[NAMESPACE_TAGS].ref,
-			      strlen(ref_namespace[NAMESPACE_TAGS].ref)))) {
+		     starts_with(rs->items[i].src,
+				 ref_namespace[NAMESPACE_TAGS].ref))) {
 			int j;
 
 			free(rs->items[i].src);
@@ -982,6 +981,8 @@ static int update_local_ref(struct ref *ref,
 		uint64_t t_before = getnanotime();
 		fast_forward = repo_in_merge_bases(the_repository, current,
 						   updated);
+		if (fast_forward < 0)
+			exit(128);
 		forced_updates_ms += (getnanotime() - t_before) / 1000000;
 	} else {
 		fast_forward = 1;

diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index 3885a9c..919282e 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c

@@ -20,10 +20,10 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 {
 	struct ref_sorting *sorting;
 	struct string_list sorting_options = STRING_LIST_INIT_DUP;
-	int icase = 0;
+	int icase = 0, include_root_refs = 0, from_stdin = 0;
 	struct ref_filter filter = REF_FILTER_INIT;
 	struct ref_format format = REF_FORMAT_INIT;
-	int from_stdin = 0;
+	unsigned int flags = FILTER_REFS_REGULAR;
 	struct strvec vec = STRVEC_INIT;
 
 	struct option opts[] = {
@@ -53,6 +53,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 		OPT_NO_CONTAINS(&filter.no_commit, N_("print only refs which don't contain the commit")),
 		OPT_BOOL(0, "ignore-case", &icase, N_("sorting and filtering are case insensitive")),
 		OPT_BOOL(0, "stdin", &from_stdin, N_("read reference patterns from stdin")),
+		OPT_BOOL(0, "include-root-refs", &include_root_refs, N_("also include HEAD ref and pseudorefs")),
 		OPT_END(),
 	};
 
@@ -96,8 +97,11 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 		filter.name_patterns = argv;
 	}
 
+	if (include_root_refs)
+		flags |= FILTER_REFS_ROOT_REFS;
+
 	filter.match_as_path = 1;
-	filter_and_format_refs(&filter, FILTER_REFS_ALL, sorting, &format);
+	filter_and_format_refs(&filter, flags, sorting, &format);
 
 	ref_filter_clear(&filter);
 	ref_sorting_release(sorting);

diff --git a/builtin/log.c b/builtin/log.c
index db1808d..e5da0d1 100644
--- a/builtin/log.c
+++ b/builtin/log.c

@@ -1625,7 +1625,7 @@ static struct commit *get_base_commit(const char *base_commit,
 {
 	struct commit *base = NULL;
 	struct commit **rev;
-	int i = 0, rev_nr = 0, auto_select, die_on_failure;
+	int i = 0, rev_nr = 0, auto_select, die_on_failure, ret;
 
 	switch (auto_base) {
 	case AUTO_BASE_NEVER:
@@ -1658,7 +1658,7 @@ static struct commit *get_base_commit(const char *base_commit,
 		struct branch *curr_branch = branch_get(NULL);
 		const char *upstream = branch_get_upstream(curr_branch, NULL);
 		if (upstream) {
-			struct commit_list *base_list;
+			struct commit_list *base_list = NULL;
 			struct commit *commit;
 			struct object_id oid;
 
@@ -1669,11 +1669,12 @@ static struct commit *get_base_commit(const char *base_commit,
 					return NULL;
 			}
 			commit = lookup_commit_or_die(&oid, "upstream base");
-			base_list = repo_get_merge_bases_many(the_repository,
-							      commit, total,
-							      list);
-			/* There should be one and only one merge base. */
-			if (!base_list || base_list->next) {
+			if (repo_get_merge_bases_many(the_repository,
+						      commit, total,
+						      list,
+						      &base_list) < 0 ||
+			    /* There should be one and only one merge base. */
+			    !base_list || base_list->next) {
 				if (die_on_failure) {
 					die(_("could not find exact merge base"));
 				} else {
@@ -1704,11 +1705,11 @@ static struct commit *get_base_commit(const char *base_commit,
 	 */
 	while (rev_nr > 1) {
 		for (i = 0; i < rev_nr / 2; i++) {
-			struct commit_list *merge_base;
-			merge_base = repo_get_merge_bases(the_repository,
-							  rev[2 * i],
-							  rev[2 * i + 1]);
-			if (!merge_base || merge_base->next) {
+			struct commit_list *merge_base = NULL;
+			if (repo_get_merge_bases(the_repository,
+						 rev[2 * i],
+						 rev[2 * i + 1], &merge_base) < 0 ||
+			    !merge_base || merge_base->next) {
 				if (die_on_failure) {
 					die(_("failed to find exact merge base"));
 				} else {
@@ -1725,7 +1726,10 @@ static struct commit *get_base_commit(const char *base_commit,
 		rev_nr = DIV_ROUND_UP(rev_nr, 2);
 	}
 
-	if (!repo_in_merge_bases(the_repository, base, rev[0])) {
+	ret = repo_in_merge_bases(the_repository, base, rev[0]);
+	if (ret < 0)
+		exit(128);
+	if (!ret) {
 		if (die_on_failure) {
 			die(_("base commit should be the ancestor of revision list"));
 		} else {

diff --git a/builtin/merge-base.c b/builtin/merge-base.c
index d26e8fb..5a8e729 100644
--- a/builtin/merge-base.c
+++ b/builtin/merge-base.c

@@ -10,10 +10,13 @@
 
 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 {
-	struct commit_list *result, *r;
+	struct commit_list *result = NULL, *r;
 
-	result = repo_get_merge_bases_many_dirty(the_repository, rev[0],
-						 rev_nr - 1, rev + 1);
+	if (repo_get_merge_bases_many_dirty(the_repository, rev[0],
+					    rev_nr - 1, rev + 1, &result) < 0) {
+		free_commit_list(result);
+		return -1;
+	}
 
 	if (!result)
 		return 1;
@@ -74,13 +77,17 @@ static int handle_independent(int count, const char **args)
 static int handle_octopus(int count, const char **args, int show_all)
 {
 	struct commit_list *revs = NULL;
-	struct commit_list *result, *rev;
+	struct commit_list *result = NULL, *rev;
 	int i;
 
 	for (i = count - 1; i >= 0; i--)
 		commit_list_insert(get_commit_reference(args[i]), &revs);
 
-	result = get_octopus_merge_bases(revs);
+	if (get_octopus_merge_bases(revs, &result) < 0) {
+		free_commit_list(revs);
+		free_commit_list(result);
+		return 128;
+	}
 	free_commit_list(revs);
 	reduce_heads_replace(&result);
 
@@ -100,12 +107,16 @@ static int handle_octopus(int count, const char **args, int show_all)
 static int handle_is_ancestor(int argc, const char **argv)
 {
 	struct commit *one, *two;
+	int ret;
 
 	if (argc != 2)
 		die("--is-ancestor takes exactly two commits");
 	one = get_commit_reference(argv[0]);
 	two = get_commit_reference(argv[1]);
-	if (repo_in_merge_bases(the_repository, one, two))
+	ret = repo_in_merge_bases(the_repository, one, two);
+	if (ret < 0)
+		exit(128);
+	if (ret)
 		return 0;
 	else
 		return 1;

diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index 3bdec53..05d0cad 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c

@@ -429,41 +429,56 @@ static int real_merge(struct merge_tree_options *o,
 	struct merge_options opt;
 
 	copy_merge_options(&opt, &o->merge_options);
-	parent1 = get_merge_parent(branch1);
-	if (!parent1)
-		help_unknown_ref(branch1, "merge-tree",
-				 _("not something we can merge"));
-
-	parent2 = get_merge_parent(branch2);
-	if (!parent2)
-		help_unknown_ref(branch2, "merge-tree",
-				 _("not something we can merge"));
-
 	opt.show_rename_progress = 0;
 
 	opt.branch1 = branch1;
 	opt.branch2 = branch2;
 
 	if (merge_base) {
-		struct commit *base_commit;
 		struct tree *base_tree, *parent1_tree, *parent2_tree;
 
-		base_commit = lookup_commit_reference_by_name(merge_base);
-		if (!base_commit)
-			die(_("could not lookup commit '%s'"), merge_base);
+		/*
+		 * We actually only need the trees because we already
+		 * have a merge base.
+		 */
+		struct object_id base_oid, head_oid, merge_oid;
+
+		if (repo_get_oid_treeish(the_repository, merge_base, &base_oid))
+			die(_("could not parse as tree '%s'"), merge_base);
+		base_tree = parse_tree_indirect(&base_oid);
+		if (!base_tree)
+			die(_("unable to read tree (%s)"), oid_to_hex(&base_oid));
+		if (repo_get_oid_treeish(the_repository, branch1, &head_oid))
+			die(_("could not parse as tree '%s'"), branch1);
+		parent1_tree = parse_tree_indirect(&head_oid);
+		if (!parent1_tree)
+			die(_("unable to read tree (%s)"), oid_to_hex(&head_oid));
+		if (repo_get_oid_treeish(the_repository, branch2, &merge_oid))
+			die(_("could not parse as tree '%s'"), branch2);
+		parent2_tree = parse_tree_indirect(&merge_oid);
+		if (!parent2_tree)
+			die(_("unable to read tree (%s)"), oid_to_hex(&merge_oid));
 
 		opt.ancestor = merge_base;
-		base_tree = repo_get_commit_tree(the_repository, base_commit);
-		parent1_tree = repo_get_commit_tree(the_repository, parent1);
-		parent2_tree = repo_get_commit_tree(the_repository, parent2);
 		merge_incore_nonrecursive(&opt, base_tree, parent1_tree, parent2_tree, &result);
 	} else {
+		parent1 = get_merge_parent(branch1);
+		if (!parent1)
+			help_unknown_ref(branch1, "merge-tree",
+					 _("not something we can merge"));
+
+		parent2 = get_merge_parent(branch2);
+		if (!parent2)
+			help_unknown_ref(branch2, "merge-tree",
+					 _("not something we can merge"));
+
 		/*
 		 * Get the merge bases, in reverse order; see comment above
 		 * merge_incore_recursive in merge-ort.h
 		 */
-		merge_bases = repo_get_merge_bases(the_repository, parent1,
-						   parent2);
+		if (repo_get_merge_bases(the_repository, parent1,
+					 parent2, &merge_bases) < 0)
+			exit(128);
 		if (!merge_bases && !o->allow_unrelated_histories)
 			die(_("refusing to merge unrelated histories"));
 		merge_bases = reverse_commit_list(merge_bases);

diff --git a/builtin/merge.c b/builtin/merge.c
index 935c8a5..a0ba1f9 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c

@@ -1513,13 +1513,20 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
 	if (!remoteheads)
 		; /* already up-to-date */
-	else if (!remoteheads->next)
-		common = repo_get_merge_bases(the_repository, head_commit,
-					      remoteheads->item);
-	else {
+	else if (!remoteheads->next) {
+		if (repo_get_merge_bases(the_repository, head_commit,
+					 remoteheads->item, &common) < 0) {
+			ret = 2;
+			goto done;
+		}
+	} else {
 		struct commit_list *list = remoteheads;
 		commit_list_insert(head_commit, &list);
-		common = get_octopus_merge_bases(list);
+		if (get_octopus_merge_bases(list, &common) < 0) {
+			free(list);
+			ret = 2;
+			goto done;
+		}
 		free(list);
 	}
 
@@ -1626,7 +1633,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 		struct commit_list *j;
 
 		for (j = remoteheads; j; j = j->next) {
-			struct commit_list *common_one;
+			struct commit_list *common_one = NULL;
 			struct commit *common_item;
 
 			/*
@@ -1634,9 +1641,10 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 			 * merge_bases again, otherwise "git merge HEAD^
 			 * HEAD^^" would be missed.
 			 */
-			common_one = repo_get_merge_bases(the_repository,
-							  head_commit,
-							  j->item);
+			if (repo_get_merge_bases(the_repository, head_commit,
+						 j->item, &common_one) < 0)
+				exit(128);
+
 			common_item = common_one->item;
 			free_commit_list(common_one);
 			if (!oideq(&common_item->object.oid, &j->item->object.oid)) {

diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index 2dd1807..ad9930c 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c

@@ -15,6 +15,7 @@
 #include "commit-slab.h"
 #include "commit-graph.h"
 #include "wildmatch.h"
+#include "mem-pool.h"
 
 /*
  * One day.  See the 'name a rev shortly after epoch' test in t6120 when
@@ -155,30 +156,25 @@ static struct rev_name *create_or_update_name(struct commit *commit,
 	return name;
 }
 
-static char *get_parent_name(const struct rev_name *name, int parent_number)
+static char *get_parent_name(const struct rev_name *name, int parent_number,
+			     struct mem_pool *string_pool)
 {
-	struct strbuf sb = STRBUF_INIT;
 	size_t len;
 
 	strip_suffix(name->tip_name, "^0", &len);
 	if (name->generation > 0) {
-		strbuf_grow(&sb, len +
-			    1 + decimal_width(name->generation) +
-			    1 + decimal_width(parent_number));
-		strbuf_addf(&sb, "%.*s~%d^%d", (int)len, name->tip_name,
-			    name->generation, parent_number);
+		return mem_pool_strfmt(string_pool, "%.*s~%d^%d",
+				       (int)len, name->tip_name,
+				       name->generation, parent_number);
 	} else {
-		strbuf_grow(&sb, len +
-			    1 + decimal_width(parent_number));
-		strbuf_addf(&sb, "%.*s^%d", (int)len, name->tip_name,
-			    parent_number);
+		return mem_pool_strfmt(string_pool, "%.*s^%d",
+				       (int)len, name->tip_name, parent_number);
 	}
-	return strbuf_detach(&sb, NULL);
 }
 
 static void name_rev(struct commit *start_commit,
 		const char *tip_name, timestamp_t taggerdate,
-		int from_tag, int deref)
+		int from_tag, int deref, struct mem_pool *string_pool)
 {
 	struct prio_queue queue;
 	struct commit *commit;
@@ -195,9 +191,10 @@ static void name_rev(struct commit *start_commit,
 	if (!start_name)
 		return;
 	if (deref)
-		start_name->tip_name = xstrfmt("%s^0", tip_name);
+		start_name->tip_name = mem_pool_strfmt(string_pool, "%s^0",
+						       tip_name);
 	else
-		start_name->tip_name = xstrdup(tip_name);
+		start_name->tip_name = mem_pool_strdup(string_pool, tip_name);
 
 	memset(&queue, 0, sizeof(queue)); /* Use the prio_queue as LIFO */
 	prio_queue_put(&queue, start_commit);
@@ -235,7 +232,8 @@ static void name_rev(struct commit *start_commit,
 				if (parent_number > 1)
 					parent_name->tip_name =
 						get_parent_name(name,
-								parent_number);
+								parent_number,
+								string_pool);
 				else
 					parent_name->tip_name = name->tip_name;
 				ALLOC_GROW(parents_to_queue,
@@ -415,7 +413,7 @@ static int name_ref(const char *path, const struct object_id *oid,
 	return 0;
 }
 
-static void name_tips(void)
+static void name_tips(struct mem_pool *string_pool)
 {
 	int i;
 
@@ -428,7 +426,7 @@ static void name_tips(void)
 		struct tip_table_entry *e = &tip_table.table[i];
 		if (e->commit) {
 			name_rev(e->commit, e->refname, e->taggerdate,
-				 e->from_tag, e->deref);
+				 e->from_tag, e->deref, string_pool);
 		}
 	}
 }
@@ -561,6 +559,7 @@ static void name_rev_line(char *p, struct name_ref_data *data)
 
 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 {
+	struct mem_pool string_pool;
 	struct object_array revs = OBJECT_ARRAY_INIT;
 	int all = 0, annotate_stdin = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 	struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
@@ -587,6 +586,7 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 		OPT_END(),
 	};
 
+	mem_pool_init(&string_pool, 0);
 	init_commit_rev_name(&rev_names);
 	git_config(git_default_config, NULL);
 	argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
@@ -648,7 +648,7 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 	adjust_cutoff_timestamp_for_slop();
 
 	for_each_ref(name_ref, &data);
-	name_tips();
+	name_tips(&string_pool);
 
 	if (annotate_stdin) {
 		struct strbuf sb = STRBUF_INIT;
@@ -676,6 +676,7 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
 				  always, allow_undefined, data.name_only);
 	}
 
+	UNLEAK(string_pool);
 	UNLEAK(revs);
 	return 0;
 }

diff --git a/builtin/pull.c b/builtin/pull.c
index 73a68b7..72cbb76 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c

@@ -815,7 +815,7 @@ static int get_octopus_merge_base(struct object_id *merge_base,
 		const struct object_id *merge_head,
 		const struct object_id *fork_point)
 {
-	struct commit_list *revs = NULL, *result;
+	struct commit_list *revs = NULL, *result = NULL;
 
 	commit_list_insert(lookup_commit_reference(the_repository, curr_head),
 			   &revs);
@@ -825,7 +825,8 @@ static int get_octopus_merge_base(struct object_id *merge_base,
 		commit_list_insert(lookup_commit_reference(the_repository, fork_point),
 				   &revs);
 
-	result = get_octopus_merge_bases(revs);
+	if (get_octopus_merge_bases(revs, &result) < 0)
+		exit(128);
 	free_commit_list(revs);
 	reduce_heads_replace(&result);
 
@@ -926,6 +927,8 @@ static int get_can_ff(struct object_id *orig_head,
 	merge_head = lookup_commit_reference(the_repository, orig_merge_head);
 	ret = repo_is_descendant_of(the_repository, merge_head, list);
 	free_commit_list(list);
+	if (ret < 0)
+		exit(128);
 	return ret;
 }
 
@@ -950,6 +953,8 @@ static int already_up_to_date(struct object_id *orig_head,
 		commit_list_insert(theirs, &list);
 		ok = repo_is_descendant_of(the_repository, ours, list);
 		free_commit_list(list);
+		if (ok < 0)
+			exit(128);
 		if (!ok)
 			return 0;
 	}

diff --git a/builtin/read-tree.c b/builtin/read-tree.c
index 20e7db1..1ffd863 100644
--- a/builtin/read-tree.c
+++ b/builtin/read-tree.c

@@ -261,7 +261,8 @@ int cmd_read_tree(int argc, const char **argv, const char *cmd_prefix)
 	cache_tree_free(&the_index.cache_tree);
 	for (i = 0; i < nr_trees; i++) {
 		struct tree *tree = trees[i];
-		parse_tree(tree);
+		if (parse_tree(tree) < 0)
+			return 128;
 		init_tree_desc(t+i, tree->buffer, tree->size);
 	}
 	if (unpack_trees(nr_trees, t, &opts))

diff --git a/builtin/rebase.c b/builtin/rebase.c
index 6ead946..be78769 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c

@@ -867,7 +867,8 @@ static int can_fast_forward(struct commit *onto, struct commit *upstream,
 	if (!upstream)
 		goto done;
 
-	merge_bases = repo_get_merge_bases(the_repository, upstream, head);
+	if (repo_get_merge_bases(the_repository, upstream, head, &merge_bases) < 0)
+		exit(128);
 	if (!merge_bases || merge_bases->next)
 		goto done;
 
@@ -886,8 +887,9 @@ static void fill_branch_base(struct rebase_options *options,
 {
 	struct commit_list *merge_bases = NULL;
 
-	merge_bases = repo_get_merge_bases(the_repository, options->onto,
-					   options->orig_head);
+	if (repo_get_merge_bases(the_repository, options->onto,
+				 options->orig_head, &merge_bases) < 0)
+		exit(128);
 	if (!merge_bases || merge_bases->next)
 		oidcpy(branch_base, null_oid());
 	else

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index db65607..56d8a77 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c

@@ -1526,6 +1526,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 	    starts_with(name, "refs/heads/")) {
 		struct object *old_object, *new_object;
 		struct commit *old_commit, *new_commit;
+		int ret2;
 
 		old_object = parse_object(the_repository, old_oid);
 		new_object = parse_object(the_repository, new_oid);
@@ -1539,7 +1540,10 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 		}
 		old_commit = (struct commit *)old_object;
 		new_commit = (struct commit *)new_object;
-		if (!repo_in_merge_bases(the_repository, old_commit, new_commit)) {
+		ret2 = repo_in_merge_bases(the_repository, old_commit, new_commit);
+		if (ret2 < 0)
+			exit(128);
+		if (!ret2) {
 			rp_error("denying non-fast-forward %s"
 				 " (you should pull first)", name);
 			ret = "non-fast-forward";

diff --git a/builtin/reset.c b/builtin/reset.c
index f0bf29a..1d62ff6 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c

@@ -116,6 +116,10 @@ static int reset_index(const char *ref, const struct object_id *oid, int reset_t
 
 	if (reset_type == MIXED || reset_type == HARD) {
 		tree = parse_tree_indirect(oid);
+		if (!tree) {
+			error(_("unable to read tree (%s)"), oid_to_hex(oid));
+			goto out;
+		}
 		prime_cache_tree(the_repository, the_repository->index, tree);
 	}
 

diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index b3f4783..ec455aa 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c

@@ -545,6 +545,18 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 	 *
 	 * Let "--missing" to conditionally set fetch_if_missing.
 	 */
+	/*
+	 * NEEDSWORK: These loops that attempt to find presence of
+	 * options without understanding that the options they are
+	 * skipping are broken (e.g., it would not know "--grep
+	 * --exclude-promisor-objects" is not triggering
+	 * "--exclude-promisor-objects" option).  We really need
+	 * setup_revisions() to have a mechanism to allow and disallow
+	 * some sets of options for different commands (like rev-list,
+	 * replay, etc). Such a mechanism should do an early parsing
+	 * of options and be able to manage the `--missing=...` and
+	 * `--exclude-promisor-objects` options below.
+	 */
 	for (i = 1; i < argc; i++) {
 		const char *arg = argv[i];
 		if (!strcmp(arg, "--exclude-promisor-objects")) {
@@ -753,8 +765,12 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 
 	if (arg_print_omitted)
 		oidset_init(&omitted_objects, DEFAULT_OIDSET_SIZE);
-	if (arg_missing_action == MA_PRINT)
+	if (arg_missing_action == MA_PRINT) {
 		oidset_init(&missing_objects, DEFAULT_OIDSET_SIZE);
+		/* Add missing tips */
+		oidset_insert_from_set(&missing_objects, &revs.missing_commits);
+		oidset_clear(&revs.missing_commits);
+	}
 
 	traverse_commit_list_filtered(
 		&revs, show_commit, show_object, &info,

diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index d089876..181c703 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c

@@ -297,7 +297,7 @@ static int try_difference(const char *arg)
 		show_rev(NORMAL, &end_oid, end);
 		show_rev(symmetric ? NORMAL : REVERSED, &start_oid, start);
 		if (symmetric) {
-			struct commit_list *exclude;
+			struct commit_list *exclude = NULL;
 			struct commit *a, *b;
 			a = lookup_commit_reference(the_repository, &start_oid);
 			b = lookup_commit_reference(the_repository, &end_oid);
@@ -305,7 +305,8 @@ static int try_difference(const char *arg)
 				*dotdot = '.';
 				return 0;
 			}
-			exclude = repo_get_merge_bases(the_repository, a, b);
+			if (repo_get_merge_bases(the_repository, a, b, &exclude) < 0)
+				exit(128);
 			while (exclude) {
 				struct commit *commit = pop_commit(&exclude);
 				show_rev(REVERSED, &commit->object.oid, NULL);

diff --git a/builtin/upload-pack.c b/builtin/upload-pack.c
index 9b021ef..15afb97 100644
--- a/builtin/upload-pack.c
+++ b/builtin/upload-pack.c

@@ -8,6 +8,7 @@
 #include "replace-object.h"
 #include "upload-pack.h"
 #include "serve.h"
+#include "commit.h"
 
 static const char * const upload_pack_usage[] = {
 	N_("git-upload-pack [--[no-]strict] [--timeout=<n>] [--stateless-rpc]\n"
@@ -37,6 +38,7 @@ int cmd_upload_pack(int argc, const char **argv, const char *prefix)
 
 	packet_trace_identity("upload-pack");
 	disable_replace_refs();
+	save_commit_buffer = 0;
 
 	argc = parse_options(argc, argv, prefix, options, upload_pack_usage, 0);
 

diff --git a/cache-tree.c b/cache-tree.c
index 64678fe..80ca832 100644
--- a/cache-tree.c
+++ b/cache-tree.c

@@ -778,8 +778,8 @@ static void prime_cache_tree_rec(struct repository *r,
 			struct cache_tree_sub *sub;
 			struct tree *subtree = lookup_tree(r, &entry.oid);
 
-			if (!subtree->object.parsed)
-				parse_tree(subtree);
+			if (parse_tree(subtree) < 0)
+				exit(128);
 			sub = cache_tree_sub(it, entry.path);
 			sub->cache_tree = cache_tree();
 

diff --git a/commit-reach.c b/commit-reach.c
index ecc913f..8f9b008 100644
--- a/commit-reach.c
+++ b/commit-reach.c

@@ -49,13 +49,14 @@ static int queue_has_nonstale(struct prio_queue *queue)
 }
 
 /* all input commits in one and twos[] must have been parsed! */
-static struct commit_list *paint_down_to_common(struct repository *r,
-						struct commit *one, int n,
-						struct commit **twos,
-						timestamp_t min_generation)
+static int paint_down_to_common(struct repository *r,
+				struct commit *one, int n,
+				struct commit **twos,
+				timestamp_t min_generation,
+				int ignore_missing_commits,
+				struct commit_list **result)
 {
 	struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
-	struct commit_list *result = NULL;
 	int i;
 	timestamp_t last_gen = GENERATION_NUMBER_INFINITY;
 
@@ -64,8 +65,8 @@ static struct commit_list *paint_down_to_common(struct repository *r,
 
 	one->object.flags |= PARENT1;
 	if (!n) {
-		commit_list_append(one, &result);
-		return result;
+		commit_list_append(one, result);
+		return 0;
 	}
 	prio_queue_put(&queue, one);
 
@@ -93,7 +94,7 @@ static struct commit_list *paint_down_to_common(struct repository *r,
 		if (flags == (PARENT1 | PARENT2)) {
 			if (!(commit->object.flags & RESULT)) {
 				commit->object.flags |= RESULT;
-				commit_list_insert_by_date(commit, &result);
+				commit_list_insert_by_date(commit, result);
 			}
 			/* Mark parents of a found merge stale */
 			flags |= STALE;
@@ -104,67 +105,97 @@ static struct commit_list *paint_down_to_common(struct repository *r,
 			parents = parents->next;
 			if ((p->object.flags & flags) == flags)
 				continue;
-			if (repo_parse_commit(r, p))
-				return NULL;
+			if (repo_parse_commit(r, p)) {
+				clear_prio_queue(&queue);
+				free_commit_list(*result);
+				*result = NULL;
+				/*
+				 * At this stage, we know that the commit is
+				 * missing: `repo_parse_commit()` uses
+				 * `OBJECT_INFO_DIE_IF_CORRUPT` and therefore
+				 * corrupt commits would already have been
+				 * dispatched with a `die()`.
+				 */
+				if (ignore_missing_commits)
+					return 0;
+				return error(_("could not parse commit %s"),
+					     oid_to_hex(&p->object.oid));
+			}
 			p->object.flags |= flags;
 			prio_queue_put(&queue, p);
 		}
 	}
 
 	clear_prio_queue(&queue);
-	return result;
+	return 0;
 }
 
-static struct commit_list *merge_bases_many(struct repository *r,
-					    struct commit *one, int n,
-					    struct commit **twos)
+static int merge_bases_many(struct repository *r,
+			    struct commit *one, int n,
+			    struct commit **twos,
+			    struct commit_list **result)
 {
 	struct commit_list *list = NULL;
-	struct commit_list *result = NULL;
 	int i;
 
 	for (i = 0; i < n; i++) {
-		if (one == twos[i])
+		if (one == twos[i]) {
 			/*
 			 * We do not mark this even with RESULT so we do not
 			 * have to clean it up.
 			 */
-			return commit_list_insert(one, &result);
+			*result = commit_list_insert(one, result);
+			return 0;
+		}
 	}
 
+	if (!one)
+		return 0;
 	if (repo_parse_commit(r, one))
-		return NULL;
+		return error(_("could not parse commit %s"),
+			     oid_to_hex(&one->object.oid));
 	for (i = 0; i < n; i++) {
+		if (!twos[i])
+			return 0;
 		if (repo_parse_commit(r, twos[i]))
-			return NULL;
+			return error(_("could not parse commit %s"),
+				     oid_to_hex(&twos[i]->object.oid));
 	}
 
-	list = paint_down_to_common(r, one, n, twos, 0);
+	if (paint_down_to_common(r, one, n, twos, 0, 0, &list)) {
+		free_commit_list(list);
+		return -1;
+	}
 
 	while (list) {
 		struct commit *commit = pop_commit(&list);
 		if (!(commit->object.flags & STALE))
-			commit_list_insert_by_date(commit, &result);
+			commit_list_insert_by_date(commit, result);
 	}
-	return result;
+	return 0;
 }
 
-struct commit_list *get_octopus_merge_bases(struct commit_list *in)
+int get_octopus_merge_bases(struct commit_list *in, struct commit_list **result)
 {
-	struct commit_list *i, *j, *k, *ret = NULL;
+	struct commit_list *i, *j, *k;
 
 	if (!in)
-		return ret;
+		return 0;
 
-	commit_list_insert(in->item, &ret);
+	commit_list_insert(in->item, result);
 
 	for (i = in->next; i; i = i->next) {
 		struct commit_list *new_commits = NULL, *end = NULL;
 
-		for (j = ret; j; j = j->next) {
-			struct commit_list *bases;
-			bases = repo_get_merge_bases(the_repository, i->item,
-						     j->item);
+		for (j = *result; j; j = j->next) {
+			struct commit_list *bases = NULL;
+			if (repo_get_merge_bases(the_repository, i->item,
+						 j->item, &bases) < 0) {
+				free_commit_list(bases);
+				free_commit_list(*result);
+				*result = NULL;
+				return -1;
+			}
 			if (!new_commits)
 				new_commits = bases;
 			else
@@ -172,10 +203,10 @@ struct commit_list *get_octopus_merge_bases(struct commit_list *in)
 			for (k = bases; k; k = k->next)
 				end = k;
 		}
-		free_commit_list(ret);
-		ret = new_commits;
+		free_commit_list(*result);
+		*result = new_commits;
 	}
-	return ret;
+	return 0;
 }
 
 static int remove_redundant_no_gen(struct repository *r,
@@ -193,7 +224,7 @@ static int remove_redundant_no_gen(struct repository *r,
 	for (i = 0; i < cnt; i++)
 		repo_parse_commit(r, array[i]);
 	for (i = 0; i < cnt; i++) {
-		struct commit_list *common;
+		struct commit_list *common = NULL;
 		timestamp_t min_generation = commit_graph_generation(array[i]);
 
 		if (redundant[i])
@@ -209,8 +240,16 @@ static int remove_redundant_no_gen(struct repository *r,
 			if (curr_generation < min_generation)
 				min_generation = curr_generation;
 		}
-		common = paint_down_to_common(r, array[i], filled,
-					      work, min_generation);
+		if (paint_down_to_common(r, array[i], filled,
+					 work, min_generation, 0, &common)) {
+			clear_commit_marks(array[i], all_flags);
+			clear_commit_marks_many(filled, work, all_flags);
+			free_commit_list(common);
+			free(work);
+			free(redundant);
+			free(filled_index);
+			return -1;
+		}
 		if (array[i]->object.flags & PARENT2)
 			redundant[i] = 1;
 		for (j = 0; j < filled; j++)
@@ -375,69 +414,77 @@ static int remove_redundant(struct repository *r, struct commit **array, int cnt
 	return remove_redundant_no_gen(r, array, cnt);
 }
 
-static struct commit_list *get_merge_bases_many_0(struct repository *r,
-						  struct commit *one,
-						  int n,
-						  struct commit **twos,
-						  int cleanup)
+static int get_merge_bases_many_0(struct repository *r,
+				  struct commit *one,
+				  int n,
+				  struct commit **twos,
+				  int cleanup,
+				  struct commit_list **result)
 {
 	struct commit_list *list;
 	struct commit **rslt;
-	struct commit_list *result;
 	int cnt, i;
 
-	result = merge_bases_many(r, one, n, twos);
+	if (merge_bases_many(r, one, n, twos, result) < 0)
+		return -1;
 	for (i = 0; i < n; i++) {
 		if (one == twos[i])
-			return result;
+			return 0;
 	}
-	if (!result || !result->next) {
+	if (!*result || !(*result)->next) {
 		if (cleanup) {
 			clear_commit_marks(one, all_flags);
 			clear_commit_marks_many(n, twos, all_flags);
 		}
-		return result;
+		return 0;
 	}
 
 	/* There are more than one */
-	cnt = commit_list_count(result);
+	cnt = commit_list_count(*result);
 	CALLOC_ARRAY(rslt, cnt);
-	for (list = result, i = 0; list; list = list->next)
+	for (list = *result, i = 0; list; list = list->next)
 		rslt[i++] = list->item;
-	free_commit_list(result);
+	free_commit_list(*result);
+	*result = NULL;
 
 	clear_commit_marks(one, all_flags);
 	clear_commit_marks_many(n, twos, all_flags);
 
 	cnt = remove_redundant(r, rslt, cnt);
-	result = NULL;
+	if (cnt < 0) {
+		free(rslt);
+		return -1;
+	}
 	for (i = 0; i < cnt; i++)
-		commit_list_insert_by_date(rslt[i], &result);
+		commit_list_insert_by_date(rslt[i], result);
 	free(rslt);
-	return result;
+	return 0;
 }
 
-struct commit_list *repo_get_merge_bases_many(struct repository *r,
-					      struct commit *one,
-					      int n,
-					      struct commit **twos)
+int repo_get_merge_bases_many(struct repository *r,
+			      struct commit *one,
+			      int n,
+			      struct commit **twos,
+			      struct commit_list **result)
 {
-	return get_merge_bases_many_0(r, one, n, twos, 1);
+	return get_merge_bases_many_0(r, one, n, twos, 1, result);
 }
 
-struct commit_list *repo_get_merge_bases_many_dirty(struct repository *r,
-						    struct commit *one,
-						    int n,
-						    struct commit **twos)
+int repo_get_merge_bases_many_dirty(struct repository *r,
+				    struct commit *one,
+				    int n,
+				    struct commit **twos,
+				    struct commit_list **result)
 {
-	return get_merge_bases_many_0(r, one, n, twos, 0);
+	return get_merge_bases_many_0(r, one, n, twos, 0, result);
 }
 
-struct commit_list *repo_get_merge_bases(struct repository *r,
-					 struct commit *one,
-					 struct commit *two)
+int repo_get_merge_bases(struct repository *r,
+			 struct commit *one,
+			 struct commit *two,
+			 struct commit_list **result)
 {
-	return get_merge_bases_many_0(r, one, 1, &two, 1);
+	return get_merge_bases_many_0(r, one, 1, &two, 1, result);
 }
 
 /*
@@ -460,11 +507,13 @@ int repo_is_descendant_of(struct repository *r,
 	} else {
 		while (with_commit) {
 			struct commit *other;
+			int ret;
 
 			other = with_commit->item;
 			with_commit = with_commit->next;
-			if (repo_in_merge_bases_many(r, other, 1, &commit))
-				return 1;
+			ret = repo_in_merge_bases_many(r, other, 1, &commit, 0);
+			if (ret)
+				return ret;
 		}
 		return 0;
 	}
@@ -474,17 +523,18 @@ int repo_is_descendant_of(struct repository *r,
  * Is "commit" an ancestor of one of the "references"?
  */
 int repo_in_merge_bases_many(struct repository *r, struct commit *commit,
-			     int nr_reference, struct commit **reference)
+			     int nr_reference, struct commit **reference,
+			     int ignore_missing_commits)
 {
-	struct commit_list *bases;
+	struct commit_list *bases = NULL;
 	int ret = 0, i;
 	timestamp_t generation, max_generation = GENERATION_NUMBER_ZERO;
 
 	if (repo_parse_commit(r, commit))
-		return ret;
+		return ignore_missing_commits ? 0 : -1;
 	for (i = 0; i < nr_reference; i++) {
 		if (repo_parse_commit(r, reference[i]))
-			return ret;
+			return ignore_missing_commits ? 0 : -1;
 
 		generation = commit_graph_generation(reference[i]);
 		if (generation > max_generation)
@@ -495,10 +545,11 @@ int repo_in_merge_bases_many(struct repository *r, struct commit *commit,
 	if (generation > max_generation)
 		return ret;
 
-	bases = paint_down_to_common(r, commit,
-				     nr_reference, reference,
-				     generation);
-	if (commit->object.flags & PARENT2)
+	if (paint_down_to_common(r, commit,
+				 nr_reference, reference,
+				 generation, ignore_missing_commits, &bases))
+		ret = -1;
+	else if (commit->object.flags & PARENT2)
 		ret = 1;
 	clear_commit_marks(commit, all_flags);
 	clear_commit_marks_many(nr_reference, reference, all_flags);
@@ -551,6 +602,10 @@ struct commit_list *reduce_heads(struct commit_list *heads)
 		}
 	}
 	num_head = remove_redundant(the_repository, array, num_head);
+	if (num_head < 0) {
+		free(array);
+		return NULL;
+	}
 	for (i = 0; i < num_head; i++)
 		tail = &commit_list_insert(array[i], tail)->next;
 	free(array);
@@ -593,6 +648,8 @@ int ref_newer(const struct object_id *new_oid, const struct object_id *old_oid)
 	commit_list_insert(old_commit, &old_commit_list);
 	ret = repo_is_descendant_of(the_repository,
 				    new_commit, old_commit_list);
+	if (ret < 0)
+		exit(128);
 	free_commit_list(old_commit_list);
 	return ret;
 }

diff --git a/commit-reach.h b/commit-reach.h
index 35c4da4..bf63cc4 100644
--- a/commit-reach.h
+++ b/commit-reach.h

@@ -9,18 +9,21 @@ struct ref_filter;
 struct object_id;
 struct object_array;
 
-struct commit_list *repo_get_merge_bases(struct repository *r,
-					 struct commit *rev1,
-					 struct commit *rev2);
-struct commit_list *repo_get_merge_bases_many(struct repository *r,
-					      struct commit *one, int n,
-					      struct commit **twos);
+int repo_get_merge_bases(struct repository *r,
+			 struct commit *rev1,
+			 struct commit *rev2,
+			 struct commit_list **result);
+int repo_get_merge_bases_many(struct repository *r,
+			      struct commit *one, int n,
+			      struct commit **twos,
+			      struct commit_list **result);
 /* To be used only when object flags after this call no longer matter */
-struct commit_list *repo_get_merge_bases_many_dirty(struct repository *r,
-						    struct commit *one, int n,
-						    struct commit **twos);
+int repo_get_merge_bases_many_dirty(struct repository *r,
+				    struct commit *one, int n,
+				    struct commit **twos,
+				    struct commit_list **result);
 
-struct commit_list *get_octopus_merge_bases(struct commit_list *in);
+int get_octopus_merge_bases(struct commit_list *in, struct commit_list **result);
 
 int repo_is_descendant_of(struct repository *r,
 			  struct commit *commit,
@@ -30,7 +33,8 @@ int repo_in_merge_bases(struct repository *r,
 			struct commit *reference);
 int repo_in_merge_bases_many(struct repository *r,
 			     struct commit *commit,
-			     int nr_reference, struct commit **reference);
+			     int nr_reference, struct commit **reference,
+			     int ignore_missing_commits);
 
 /*
  * Takes a list of commits and returns a new list where those

diff --git a/commit.c b/commit.c
index ef679a0..467be9f 100644
--- a/commit.c
+++ b/commit.c

@@ -1052,7 +1052,7 @@ struct commit *get_fork_point(const char *refname, struct commit *commit)
 {
 	struct object_id oid;
 	struct rev_collect revs;
-	struct commit_list *bases;
+	struct commit_list *bases = NULL;
 	int i;
 	struct commit *ret = NULL;
 	char *full_refname;
@@ -1077,8 +1077,9 @@ struct commit *get_fork_point(const char *refname, struct commit *commit)
 	for (i = 0; i < revs.nr; i++)
 		revs.commit[i]->object.flags &= ~TMP_MARK;
 
-	bases = repo_get_merge_bases_many(the_repository, commit, revs.nr,
-					  revs.commit);
+	if (repo_get_merge_bases_many(the_repository, commit, revs.nr,
+				      revs.commit, &bases) < 0)
+		exit(128);
 
 	/*
 	 * There should be one and only one merge base, when we found

diff --git a/compat/compiler.h b/compat/compiler.h
index 10dbb65..e9ad9db 100644
--- a/compat/compiler.h
+++ b/compat/compiler.h

@@ -1,7 +1,6 @@
 #ifndef COMPILER_H
 #define COMPILER_H
 
-#include "git-compat-util.h"
 #include "strbuf.h"
 
 #ifdef __GLIBC__

diff --git a/compat/disk.h b/compat/disk.h
index 6c979c2..23bc1be 100644
--- a/compat/disk.h
+++ b/compat/disk.h

@@ -1,7 +1,6 @@
 #ifndef COMPAT_DISK_H
 #define COMPAT_DISK_H
 
-#include "git-compat-util.h"
 #include "abspath.h"
 #include "gettext.h"
 

diff --git a/diff-lib.c b/diff-lib.c
index 6c8df04..5e8717c 100644
--- a/diff-lib.c
+++ b/diff-lib.c

@@ -570,7 +570,7 @@ void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb)
 {
 	int i;
 	struct commit *mb_child[2] = {0};
-	struct commit_list *merge_bases;
+	struct commit_list *merge_bases = NULL;
 
 	for (i = 0; i < revs->pending.nr; i++) {
 		struct object *obj = revs->pending.objects[i].item;
@@ -597,7 +597,8 @@ void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb)
 		mb_child[1] = lookup_commit_reference(the_repository, &oid);
 	}
 
-	merge_bases = repo_get_merge_bases(the_repository, mb_child[0], mb_child[1]);
+	if (repo_get_merge_bases(the_repository, mb_child[0], mb_child[1], &merge_bases) < 0)
+		exit(128);
 	if (!merge_bases)
 		die(_("no merge base found"));
 	if (merge_bases->next)

diff --git a/environment.c b/environment.c
index 90632a3..60706ea 100644
--- a/environment.c
+++ b/environment.c

@@ -207,6 +207,9 @@ void setup_git_env(const char *git_dir)
 	shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
 	if (shallow_file)
 		set_alternate_shallow_file(the_repository, shallow_file, 0);
+
+	if (git_env_bool(NO_LAZY_FETCH_ENVIRONMENT, 0))
+		fetch_if_missing = 0;
 }
 
 int is_bare_repository(void)

diff --git a/environment.h b/environment.h
index e5351c9..5cec19c 100644
--- a/environment.h
+++ b/environment.h

@@ -36,6 +36,7 @@ const char *getenv_safe(struct strvec *argv, const char *name);
 #define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
 #define NO_REPLACE_OBJECTS_ENVIRONMENT "GIT_NO_REPLACE_OBJECTS"
 #define GIT_REPLACE_REF_BASE_ENVIRONMENT "GIT_REPLACE_REF_BASE"
+#define NO_LAZY_FETCH_ENVIRONMENT "GIT_NO_LAZY_FETCH"
 #define GITATTRIBUTES_FILE ".gitattributes"
 #define INFOATTRIBUTES_FILE "info/attributes"
 #define ATTRIBUTE_MACRO_PREFIX "[attr]"

diff --git a/git.c b/git.c
index 7068a18..5265f92 100644
--- a/git.c
+++ b/git.c

@@ -4,6 +4,7 @@
 #include "exec-cmd.h"
 #include "gettext.h"
 #include "help.h"
+#include "object-file.h"
 #include "pager.h"
 #include "read-cache-ll.h"
 #include "run-command.h"
@@ -186,6 +187,11 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
 			use_pager = 0;
 			if (envchanged)
 				*envchanged = 1;
+		} else if (!strcmp(cmd, "--no-lazy-fetch")) {
+			fetch_if_missing = 0;
+			setenv(NO_LAZY_FETCH_ENVIRONMENT, "1", 1);
+			if (envchanged)
+				*envchanged = 1;
 		} else if (!strcmp(cmd, "--no-replace-objects")) {
 			disable_replace_refs();
 			setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);

diff --git a/http-push.c b/http-push.c
index 12d1113..33db41b 100644
--- a/http-push.c
+++ b/http-push.c

@@ -1575,8 +1575,11 @@ static int verify_merge_base(struct object_id *head_oid, struct ref *remote)
 	struct commit *head = lookup_commit_or_die(head_oid, "HEAD");
 	struct commit *branch = lookup_commit_or_die(&remote->old_oid,
 						     remote->name);
+	int ret = repo_in_merge_bases(the_repository, branch, head);
 
-	return repo_in_merge_bases(the_repository, branch, head);
+	if (ret < 0)
+		exit(128);
+	return ret;
 }
 
 static int delete_remote_branch(const char *pattern, int force)

diff --git a/list-objects-filter.c b/list-objects-filter.c
index da287cc..4346f8d 100644
--- a/list-objects-filter.c
+++ b/list-objects-filter.c

@@ -711,15 +711,6 @@ static void filter_combine__free(void *filter_data)
 	free(d);
 }
 
-static void add_all(struct oidset *dest, struct oidset *src) {
-	struct oidset_iter iter;
-	struct object_id *src_oid;
-
-	oidset_iter_init(src, &iter);
-	while ((src_oid = oidset_iter_next(&iter)) != NULL)
-		oidset_insert(dest, src_oid);
-}
-
 static void filter_combine__finalize_omits(
 	struct oidset *omits,
 	void *filter_data)
@@ -728,7 +719,7 @@ static void filter_combine__finalize_omits(
 	size_t sub;
 
 	for (sub = 0; sub < d->nr; sub++) {
-		add_all(omits, &d->sub[sub].omits);
+		oidset_insert_from_set(omits, &d->sub[sub].omits);
 		oidset_clear(&d->sub[sub].omits);
 	}
 }

diff --git a/log-tree.c b/log-tree.c
index 337b933..e5438b0 100644
--- a/log-tree.c
+++ b/log-tree.c

@@ -1011,7 +1011,7 @@ static int do_remerge_diff(struct rev_info *opt,
 			   struct object_id *oid)
 {
 	struct merge_options o;
-	struct commit_list *bases;
+	struct commit_list *bases = NULL;
 	struct merge_result res = {0};
 	struct pretty_print_context ctx = {0};
 	struct commit *parent1 = parents->item;
@@ -1036,7 +1036,8 @@ static int do_remerge_diff(struct rev_info *opt,
 	/* Parse the relevant commits and get the merge bases */
 	parse_commit_or_die(parent1);
 	parse_commit_or_die(parent2);
-	bases = repo_get_merge_bases(the_repository, parent1, parent2);
+	if (repo_get_merge_bases(the_repository, parent1, parent2, &bases) < 0)
+		exit(128);
 
 	/* Re-merge the parents */
 	merge_incore_recursive(&o, bases, parent1, parent2, &res);

diff --git a/mem-pool.c b/mem-pool.c
index c7d6256..2078c22 100644
--- a/mem-pool.c
+++ b/mem-pool.c

@@ -107,6 +107,45 @@ void *mem_pool_alloc(struct mem_pool *pool, size_t len)
 	return r;
 }
 
+static char *mem_pool_strvfmt(struct mem_pool *pool, const char *fmt,
+			      va_list ap)
+{
+	struct mp_block *block = pool->mp_block;
+	char *next_free = block ? block->next_free : NULL;
+	size_t available = block ? block->end - block->next_free : 0;
+	va_list cp;
+	int len, len2;
+	char *ret;
+
+	va_copy(cp, ap);
+	len = vsnprintf(next_free, available, fmt, cp);
+	va_end(cp);
+	if (len < 0)
+		BUG("your vsnprintf is broken (returned %d)", len);
+
+	ret = mem_pool_alloc(pool, len + 1);  /* 1 for NUL */
+
+	/* Shortcut; relies on mem_pool_alloc() not touching buffer contents. */
+	if (ret == next_free)
+		return ret;
+
+	len2 = vsnprintf(ret, len + 1, fmt, ap);
+	if (len2 != len)
+		BUG("your vsnprintf is broken (returns inconsistent lengths)");
+	return ret;
+}
+
+char *mem_pool_strfmt(struct mem_pool *pool, const char *fmt, ...)
+{
+	va_list ap;
+	char *ret;
+
+	va_start(ap, fmt);
+	ret = mem_pool_strvfmt(pool, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
 void *mem_pool_calloc(struct mem_pool *pool, size_t count, size_t size)
 {
 	size_t len = st_mult(count, size);

diff --git a/mem-pool.h b/mem-pool.h
index fe7507f..d1c6641 100644
--- a/mem-pool.h
+++ b/mem-pool.h

@@ -48,6 +48,11 @@ char *mem_pool_strdup(struct mem_pool *pool, const char *str);
 char *mem_pool_strndup(struct mem_pool *pool, const char *str, size_t len);
 
 /*
+ * Allocate memory from the memory pool and format a string into it.
+ */
+char *mem_pool_strfmt(struct mem_pool *pool, const char *fmt, ...);
+
+/*
  * Move the memory associated with the 'src' pool to the 'dst' pool. The 'src'
  * pool will be empty and not contain any memory. It still needs to be free'd
  * with a call to `mem_pool_discard`.

diff --git a/merge-ort.c b/merge-ort.c
index 8617bab..201f8f7 100644
--- a/merge-ort.c
+++ b/merge-ort.c

@@ -18,6 +18,7 @@
 #include "merge-ort.h"
 
 #include "alloc.h"
+#include "advice.h"
 #include "attr.h"
 #include "cache-tree.h"
 #include "commit.h"
@@ -542,6 +543,7 @@ enum conflict_and_info_types {
 	CONFLICT_SUBMODULE_HISTORY_NOT_AVAILABLE,
 	CONFLICT_SUBMODULE_MAY_HAVE_REWINDS,
 	CONFLICT_SUBMODULE_NULL_MERGE_BASE,
+	CONFLICT_SUBMODULE_CORRUPT,
 
 	/* Keep this entry _last_ in the list */
 	NB_CONFLICT_TYPES,
@@ -594,7 +596,9 @@ static const char *type_short_descriptions[] = {
 	[CONFLICT_SUBMODULE_MAY_HAVE_REWINDS] =
 		"CONFLICT (submodule may have rewinds)",
 	[CONFLICT_SUBMODULE_NULL_MERGE_BASE] =
-		"CONFLICT (submodule lacks merge base)"
+		"CONFLICT (submodule lacks merge base)",
+	[CONFLICT_SUBMODULE_CORRUPT] =
+		"CONFLICT (submodule corrupt)"
 };
 
 struct logical_conflict_info {
@@ -1657,9 +1661,10 @@ static int collect_merge_info(struct merge_options *opt,
 	info.data = opt;
 	info.show_all_errors = 1;
 
-	parse_tree(merge_base);
-	parse_tree(side1);
-	parse_tree(side2);
+	if (parse_tree(merge_base) < 0 ||
+	    parse_tree(side1) < 0 ||
+	    parse_tree(side2) < 0)
+		return -1;
 	init_tree_desc(t + 0, merge_base->buffer, merge_base->size);
 	init_tree_desc(t + 1, side1->buffer, side1->size);
 	init_tree_desc(t + 2, side2->buffer, side2->size);
@@ -1708,7 +1713,14 @@ static int find_first_merges(struct repository *repo,
 		die("revision walk setup failed");
 	while ((commit = get_revision(&revs)) != NULL) {
 		struct object *o = &(commit->object);
-		if (repo_in_merge_bases(repo, b, commit))
+		int ret = repo_in_merge_bases(repo, b, commit);
+
+		if (ret < 0) {
+			object_array_clear(&merges);
+			release_revisions(&revs);
+			return ret;
+		}
+		if (ret > 0)
 			add_object_array(o, NULL, &merges);
 	}
 	reset_revision_walk();
@@ -1723,9 +1735,17 @@ static int find_first_merges(struct repository *repo,
 		contains_another = 0;
 		for (j = 0; j < merges.nr; j++) {
 			struct commit *m2 = (struct commit *) merges.objects[j].item;
-			if (i != j && repo_in_merge_bases(repo, m2, m1)) {
-				contains_another = 1;
-				break;
+			if (i != j) {
+				int ret = repo_in_merge_bases(repo, m2, m1);
+				if (ret < 0) {
+					object_array_clear(&merges);
+					release_revisions(&revs);
+					return ret;
+				}
+				if (ret > 0) {
+					contains_another = 1;
+					break;
+				}
 			}
 		}
 
@@ -1747,7 +1767,7 @@ static int merge_submodule(struct merge_options *opt,
 {
 	struct repository subrepo;
 	struct strbuf sb = STRBUF_INIT;
-	int ret = 0;
+	int ret = 0, ret2;
 	struct commit *commit_o, *commit_a, *commit_b;
 	int parent_count;
 	struct object_array merges;
@@ -1794,8 +1814,28 @@ static int merge_submodule(struct merge_options *opt,
 	}
 
 	/* check whether both changes are forward */
-	if (!repo_in_merge_bases(&subrepo, commit_o, commit_a) ||
-	    !repo_in_merge_bases(&subrepo, commit_o, commit_b)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_o, commit_a);
+	if (ret2 < 0) {
+		path_msg(opt, CONFLICT_SUBMODULE_CORRUPT, 0,
+			 path, NULL, NULL, NULL,
+			 _("Failed to merge submodule %s "
+			   "(repository corrupt)"),
+			 path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2 > 0)
+		ret2 = repo_in_merge_bases(&subrepo, commit_o, commit_b);
+	if (ret2 < 0) {
+		path_msg(opt, CONFLICT_SUBMODULE_CORRUPT, 0,
+			 path, NULL, NULL, NULL,
+			 _("Failed to merge submodule %s "
+			   "(repository corrupt)"),
+			 path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (!ret2) {
 		path_msg(opt, CONFLICT_SUBMODULE_MAY_HAVE_REWINDS, 0,
 			 path, NULL, NULL, NULL,
 			 _("Failed to merge submodule %s "
@@ -1805,7 +1845,17 @@ static int merge_submodule(struct merge_options *opt,
 	}
 
 	/* Case #1: a is contained in b or vice versa */
-	if (repo_in_merge_bases(&subrepo, commit_a, commit_b)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_a, commit_b);
+	if (ret2 < 0) {
+		path_msg(opt, CONFLICT_SUBMODULE_CORRUPT, 0,
+			 path, NULL, NULL, NULL,
+			 _("Failed to merge submodule %s "
+			   "(repository corrupt)"),
+			 path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2 > 0) {
 		oidcpy(result, b);
 		path_msg(opt, INFO_SUBMODULE_FAST_FORWARDING, 1,
 			 path, NULL, NULL, NULL,
@@ -1814,7 +1864,17 @@ static int merge_submodule(struct merge_options *opt,
 		ret = 1;
 		goto cleanup;
 	}
-	if (repo_in_merge_bases(&subrepo, commit_b, commit_a)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_b, commit_a);
+	if (ret2 < 0) {
+		path_msg(opt, CONFLICT_SUBMODULE_CORRUPT, 0,
+			 path, NULL, NULL, NULL,
+			 _("Failed to merge submodule %s "
+			   "(repository corrupt)"),
+			 path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2 > 0) {
 		oidcpy(result, a);
 		path_msg(opt, INFO_SUBMODULE_FAST_FORWARDING, 1,
 			 path, NULL, NULL, NULL,
@@ -1839,6 +1899,14 @@ static int merge_submodule(struct merge_options *opt,
 	parent_count = find_first_merges(&subrepo, path, commit_a, commit_b,
 					 &merges);
 	switch (parent_count) {
+	case -1:
+		path_msg(opt, CONFLICT_SUBMODULE_CORRUPT, 0,
+			 path, NULL, NULL, NULL,
+			 _("Failed to merge submodule %s "
+			   "(repository corrupt)"),
+			 path);
+		ret = -1;
+		break;
 	case 0:
 		path_msg(opt, CONFLICT_SUBMODULE_FAILED_TO_MERGE, 0,
 			 path, NULL, NULL, NULL,
@@ -4376,9 +4444,11 @@ static int checkout(struct merge_options *opt,
 	unpack_opts.verbose_update = (opt->verbosity > 2);
 	unpack_opts.fn = twoway_merge;
 	unpack_opts.preserve_ignored = 0; /* FIXME: !opts->overwrite_ignore */
-	parse_tree(prev);
+	if (parse_tree(prev) < 0)
+		return -1;
 	init_tree_desc(&trees[0], prev->buffer, prev->size);
-	parse_tree(next);
+	if (parse_tree(next) < 0)
+		return -1;
 	init_tree_desc(&trees[1], next->buffer, next->size);
 
 	ret = unpack_trees(2, trees, &unpack_opts);
@@ -4556,7 +4626,7 @@ static void print_submodule_conflict_suggestion(struct string_list *csub) {
 		      " - commit the resulting index in the superproject\n"),
 		    tmp.buf, subs.buf);
 
-	printf("%s", msg.buf);
+	advise_if_enabled(ADVICE_SUBMODULE_MERGE_CONFLICT, "%s", msg.buf);
 
 	strbuf_release(&subs);
 	strbuf_release(&tmp);
@@ -4982,6 +5052,9 @@ static void merge_ort_nonrecursive_internal(struct merge_options *opt,
 
 	if (result->clean >= 0) {
 		result->tree = parse_tree_indirect(&working_tree_oid);
+		if (!result->tree)
+			die(_("unable to read tree (%s)"),
+			    oid_to_hex(&working_tree_oid));
 		/* existence of conflicted entries implies unclean */
 		result->clean &= strmap_empty(&opt->priv->conflicted);
 	}
@@ -5007,7 +5080,11 @@ static void merge_ort_internal(struct merge_options *opt,
 	struct strbuf merge_base_abbrev = STRBUF_INIT;
 
 	if (!merge_bases) {
-		merge_bases = repo_get_merge_bases(the_repository, h1, h2);
+		if (repo_get_merge_bases(the_repository, h1, h2,
+					 &merge_bases) < 0) {
+			result->clean = -1;
+			return;
+		}
 		/* See merge-ort.h:merge_incore_recursive() declaration NOTE */
 		merge_bases = reverse_commit_list(merge_bases);
 	}

diff --git a/merge-recursive.c b/merge-recursive.c
index a0c3e7a..103ee32 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c

@@ -405,7 +405,8 @@ static inline int merge_detect_rename(struct merge_options *opt)
 
 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
 {
-	parse_tree(tree);
+	if (parse_tree(tree) < 0)
+		exit(128);
 	init_tree_desc(desc, tree->buffer, tree->size);
 }
 
@@ -1139,7 +1140,13 @@ static int find_first_merges(struct repository *repo,
 		die("revision walk setup failed");
 	while ((commit = get_revision(&revs)) != NULL) {
 		struct object *o = &(commit->object);
-		if (repo_in_merge_bases(repo, b, commit))
+		int ret = repo_in_merge_bases(repo, b, commit);
+		if (ret < 0) {
+			object_array_clear(&merges);
+			release_revisions(&revs);
+			return ret;
+		}
+		if (ret)
 			add_object_array(o, NULL, &merges);
 	}
 	reset_revision_walk();
@@ -1154,9 +1161,17 @@ static int find_first_merges(struct repository *repo,
 		contains_another = 0;
 		for (j = 0; j < merges.nr; j++) {
 			struct commit *m2 = (struct commit *) merges.objects[j].item;
-			if (i != j && repo_in_merge_bases(repo, m2, m1)) {
-				contains_another = 1;
-				break;
+			if (i != j) {
+				int ret = repo_in_merge_bases(repo, m2, m1);
+				if (ret < 0) {
+					object_array_clear(&merges);
+					release_revisions(&revs);
+					return ret;
+				}
+				if (ret > 0) {
+					contains_another = 1;
+					break;
+				}
 			}
 		}
 
@@ -1192,7 +1207,7 @@ static int merge_submodule(struct merge_options *opt,
 			   const struct object_id *b)
 {
 	struct repository subrepo;
-	int ret = 0;
+	int ret = 0, ret2;
 	struct commit *commit_base, *commit_a, *commit_b;
 	int parent_count;
 	struct object_array merges;
@@ -1229,14 +1244,32 @@ static int merge_submodule(struct merge_options *opt,
 	}
 
 	/* check whether both changes are forward */
-	if (!repo_in_merge_bases(&subrepo, commit_base, commit_a) ||
-	    !repo_in_merge_bases(&subrepo, commit_base, commit_b)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_base, commit_a);
+	if (ret2 < 0) {
+		output(opt, 1, _("Failed to merge submodule %s (repository corrupt)"), path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2 > 0)
+		ret2 = repo_in_merge_bases(&subrepo, commit_base, commit_b);
+	if (ret2 < 0) {
+		output(opt, 1, _("Failed to merge submodule %s (repository corrupt)"), path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (!ret2) {
 		output(opt, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
 		goto cleanup;
 	}
 
 	/* Case #1: a is contained in b or vice versa */
-	if (repo_in_merge_bases(&subrepo, commit_a, commit_b)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_a, commit_b);
+	if (ret2 < 0) {
+		output(opt, 1, _("Failed to merge submodule %s (repository corrupt)"), path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2) {
 		oidcpy(result, b);
 		if (show(opt, 3)) {
 			output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
@@ -1249,7 +1282,13 @@ static int merge_submodule(struct merge_options *opt,
 		ret = 1;
 		goto cleanup;
 	}
-	if (repo_in_merge_bases(&subrepo, commit_b, commit_a)) {
+	ret2 = repo_in_merge_bases(&subrepo, commit_b, commit_a);
+	if (ret2 < 0) {
+		output(opt, 1, _("Failed to merge submodule %s (repository corrupt)"), path);
+		ret = -1;
+		goto cleanup;
+	}
+	if (ret2) {
 		oidcpy(result, a);
 		if (show(opt, 3)) {
 			output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
@@ -1278,6 +1317,10 @@ static int merge_submodule(struct merge_options *opt,
 	parent_count = find_first_merges(&subrepo, &merges, path,
 					 commit_a, commit_b);
 	switch (parent_count) {
+	case -1:
+		output(opt, 1,_("Failed to merge submodule %s (repository corrupt)"), path);
+		ret = -1;
+		break;
 	case 0:
 		output(opt, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
 		break;
@@ -1392,11 +1435,14 @@ static int merge_mode_and_contents(struct merge_options *opt,
 			/* FIXME: bug, what if modes didn't match? */
 			result->clean = (merge_status == 0);
 		} else if (S_ISGITLINK(a->mode)) {
-			result->clean = merge_submodule(opt, &result->blob.oid,
-							o->path,
-							&o->oid,
-							&a->oid,
-							&b->oid);
+			int clean = merge_submodule(opt, &result->blob.oid,
+						    o->path,
+						    &o->oid,
+						    &a->oid,
+						    &b->oid);
+			if (clean < 0)
+				return -1;
+			result->clean = clean;
 		} else if (S_ISLNK(a->mode)) {
 			switch (opt->recursive_variant) {
 			case MERGE_VARIANT_NORMAL:
@@ -3597,7 +3643,9 @@ static int merge_recursive_internal(struct merge_options *opt,
 	}
 
 	if (!merge_bases) {
-		merge_bases = repo_get_merge_bases(the_repository, h1, h2);
+		if (repo_get_merge_bases(the_repository, h1, h2,
+					 &merge_bases) < 0)
+			return -1;
 		merge_bases = reverse_commit_list(merge_bases);
 	}
 

diff --git a/merge.c b/merge.c
index ca89b31..563281b 100644
--- a/merge.c
+++ b/merge.c

@@ -77,7 +77,10 @@ int checkout_fast_forward(struct repository *r,
 		return -1;
 	}
 	for (i = 0; i < nr_trees; i++) {
-		parse_tree(trees[i]);
+		if (parse_tree(trees[i]) < 0) {
+			rollback_lock_file(&lock_file);
+			return -1;
+		}
 		init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
 	}
 

diff --git a/neue b/neue
deleted file mode 100644
index e69de29..0000000
--- a/neue
+++ /dev/null


diff --git a/notes-merge.c b/notes-merge.c
index 8799b52..5128293 100644
--- a/notes-merge.c
+++ b/notes-merge.c

@@ -607,7 +607,8 @@ int notes_merge(struct notes_merge_options *o,
 	assert(local && remote);
 
 	/* Find merge bases */
-	bases = repo_get_merge_bases(the_repository, local, remote);
+	if (repo_get_merge_bases(the_repository, local, remote, &bases) < 0)
+		exit(128);
 	if (!bases) {
 		base_oid = null_oid();
 		base_tree_oid = the_hash_algo->empty_tree;

diff --git a/object-name.c b/object-name.c
index 3a2ef5d..bd77695 100644
--- a/object-name.c
+++ b/object-name.c

@@ -1034,6 +1034,15 @@ static int get_oid_basic(struct repository *r, const char *str, int len,
 						len, str,
 						show_date(co_time, co_tz, DATE_MODE(RFC2822)));
 				}
+			} else if (nth == co_cnt && !is_null_oid(oid)) {
+				/*
+				 * We were asked for the Nth reflog (counting
+				 * from 0), but there were only N entries.
+				 * read_ref_at() will have returned "1" to tell
+				 * us it did not find an entry, but it did
+				 * still fill in the oid with the "old" value,
+				 * which we can use.
+				 */
 			} else {
 				if (flags & GET_OID_QUIETLY) {
 					exit(128);
@@ -1479,7 +1488,7 @@ int repo_get_oid_mb(struct repository *r,
 		    struct object_id *oid)
 {
 	struct commit *one, *two;
-	struct commit_list *mbs;
+	struct commit_list *mbs = NULL;
 	struct object_id oid_tmp;
 	const char *dots;
 	int st;
@@ -1507,7 +1516,10 @@ int repo_get_oid_mb(struct repository *r,
 	two = lookup_commit_reference_gently(r, &oid_tmp, 0);
 	if (!two)
 		return -1;
-	mbs = repo_get_merge_bases(r, one, two);
+	if (repo_get_merge_bases(r, one, two, &mbs) < 0) {
+		free_commit_list(mbs);
+		return -1;
+	}
 	if (!mbs || mbs->next)
 		st = -1;
 	else {

diff --git a/object.c b/object.c
index e6a1c4d..f11c59a 100644
--- a/object.c
+++ b/object.c

@@ -271,6 +271,7 @@ struct object *parse_object_with_flags(struct repository *r,
 				       enum parse_object_flags flags)
 {
 	int skip_hash = !!(flags & PARSE_OBJECT_SKIP_HASH_CHECK);
+	int discard_tree = !!(flags & PARSE_OBJECT_DISCARD_TREE);
 	unsigned long size;
 	enum object_type type;
 	int eaten;
@@ -298,6 +299,17 @@ struct object *parse_object_with_flags(struct repository *r,
 		return lookup_object(r, oid);
 	}
 
+	/*
+	 * If the caller does not care about the tree buffer and does not
+	 * care about checking the hash, we can simply verify that we
+	 * have the on-disk object with the correct type.
+	 */
+	if (skip_hash && discard_tree &&
+	    (!obj || obj->type == OBJ_TREE) &&
+	    oid_object_info(r, oid, NULL) == OBJ_TREE) {
+		return &lookup_tree(r, oid)->object;
+	}
+
 	buffer = repo_read_object_file(r, oid, &type, &size);
 	if (buffer) {
 		if (!skip_hash &&
@@ -311,6 +323,8 @@ struct object *parse_object_with_flags(struct repository *r,
 					  buffer, &eaten);
 		if (!eaten)
 			free(buffer);
+		if (discard_tree && type == OBJ_TREE)
+			free_tree_buffer((struct tree *)obj);
 		return obj;
 	}
 	return NULL;

diff --git a/object.h b/object.h
index 114d459..c7123ca 100644
--- a/object.h
+++ b/object.h

@@ -197,6 +197,7 @@ void *object_as_type(struct object *obj, enum object_type type, int quiet);
  */
 enum parse_object_flags {
 	PARSE_OBJECT_SKIP_HASH_CHECK = 1 << 0,
+	PARSE_OBJECT_DISCARD_TREE = 1 << 1,
 };
 struct object *parse_object(struct repository *r, const struct object_id *oid);
 struct object *parse_object_with_flags(struct repository *r,

diff --git a/oidset.c b/oidset.c
index d1e5376..91d1385 100644
--- a/oidset.c
+++ b/oidset.c

@@ -23,6 +23,16 @@ int oidset_insert(struct oidset *set, const struct object_id *oid)
 	return !added;
 }
 
+void oidset_insert_from_set(struct oidset *dest, struct oidset *src)
+{
+	struct oidset_iter iter;
+	struct object_id *src_oid;
+
+	oidset_iter_init(src, &iter);
+	while ((src_oid = oidset_iter_next(&iter)))
+		oidset_insert(dest, src_oid);
+}
+
 int oidset_remove(struct oidset *set, const struct object_id *oid)
 {
 	khiter_t pos = kh_get_oid_set(&set->set, *oid);

diff --git a/oidset.h b/oidset.h
index ba4a5a2..262f425 100644
--- a/oidset.h
+++ b/oidset.h

@@ -48,6 +48,12 @@ int oidset_contains(const struct oidset *set, const struct object_id *oid);
 int oidset_insert(struct oidset *set, const struct object_id *oid);
 
 /**
+ * Insert all the oids that are in set 'src' into set 'dest'; a copy
+ * is made of each oid inserted into set 'dest'.
+ */
+void oidset_insert_from_set(struct oidset *dest, struct oidset *src);
+
+/**
  * Remove the oid from the set.
  *
  * Returns 1 if the oid was present in the set, 0 otherwise.

diff --git a/ref-filter.c b/ref-filter.c
index be14b56..0ec29f7 100644
--- a/ref-filter.c
+++ b/ref-filter.c

@@ -2628,6 +2628,12 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
 				       each_ref_fn cb,
 				       void *cb_data)
 {
+	if (filter->kind == FILTER_REFS_KIND_MASK) {
+		/* In this case, we want to print all refs including root refs. */
+		return refs_for_each_include_root_refs(get_main_ref_store(the_repository),
+						       cb, cb_data);
+	}
+
 	if (!filter->match_as_path) {
 		/*
 		 * in this case, the patterns are applied after
@@ -2750,6 +2756,9 @@ static int ref_kind_from_refname(const char *refname)
 			return ref_kind[i].kind;
 	}
 
+	if (is_pseudoref(get_main_ref_store(the_repository), refname))
+		return FILTER_REFS_PSEUDOREFS;
+
 	return FILTER_REFS_OTHERS;
 }
 
@@ -2781,7 +2790,16 @@ static struct ref_array_item *apply_ref_filter(const char *refname, const struct
 
 	/* Obtain the current ref kind from filter_ref_kind() and ignore unwanted refs. */
 	kind = filter_ref_kind(filter, refname);
-	if (!(kind & filter->kind))
+
+	/*
+	 * Generally HEAD refs are printed with special description denoting a rebase,
+	 * detached state and so forth. This is useful when only printing the HEAD ref
+	 * But when it is being printed along with other pseudorefs, it makes sense to
+	 * keep the formatting consistent. So we mask the type to act like a pseudoref.
+	 */
+	if (filter->kind == FILTER_REFS_KIND_MASK && kind == FILTER_REFS_DETACHED_HEAD)
+		kind = FILTER_REFS_PSEUDOREFS;
+	else if (!(kind & filter->kind))
 		return NULL;
 
 	if (!filter_pattern_match(filter, refname))
@@ -3047,9 +3065,15 @@ static int do_filter_refs(struct ref_filter *filter, unsigned int type, each_ref
 			ret = for_each_fullref_in("refs/remotes/", fn, cb_data);
 		else if (filter->kind == FILTER_REFS_TAGS)
 			ret = for_each_fullref_in("refs/tags/", fn, cb_data);
-		else if (filter->kind & FILTER_REFS_ALL)
+		else if (filter->kind & FILTER_REFS_REGULAR)
 			ret = for_each_fullref_in_pattern(filter, fn, cb_data);
-		if (!ret && (filter->kind & FILTER_REFS_DETACHED_HEAD))
+
+		/*
+		 * When printing all ref types, HEAD is already included,
+		 * so we don't want to print HEAD again.
+		 */
+		if (!ret && (filter->kind != FILTER_REFS_KIND_MASK) &&
+		    (filter->kind & FILTER_REFS_DETACHED_HEAD))
 			head_ref(fn, cb_data);
 	}
 

diff --git a/ref-filter.h b/ref-filter.h
index 07cd6f6..0ca28d2 100644
--- a/ref-filter.h
+++ b/ref-filter.h

@@ -19,10 +19,13 @@
 #define FILTER_REFS_BRANCHES       0x0004
 #define FILTER_REFS_REMOTES        0x0008
 #define FILTER_REFS_OTHERS         0x0010
-#define FILTER_REFS_ALL            (FILTER_REFS_TAGS | FILTER_REFS_BRANCHES | \
+#define FILTER_REFS_REGULAR        (FILTER_REFS_TAGS | FILTER_REFS_BRANCHES | \
 				    FILTER_REFS_REMOTES | FILTER_REFS_OTHERS)
 #define FILTER_REFS_DETACHED_HEAD  0x0020
-#define FILTER_REFS_KIND_MASK      (FILTER_REFS_ALL | FILTER_REFS_DETACHED_HEAD)
+#define FILTER_REFS_PSEUDOREFS     0x0040
+#define FILTER_REFS_ROOT_REFS      (FILTER_REFS_DETACHED_HEAD | FILTER_REFS_PSEUDOREFS)
+#define FILTER_REFS_KIND_MASK      (FILTER_REFS_REGULAR | FILTER_REFS_DETACHED_HEAD | \
+				    FILTER_REFS_PSEUDOREFS)
 
 struct atom_value;
 struct ref_sorting;

diff --git a/refs.c b/refs.c
index f926126..55d2e0b 100644
--- a/refs.c
+++ b/refs.c

@@ -860,6 +860,47 @@ static int is_pseudoref_syntax(const char *refname)
 	return 1;
 }
 
+int is_pseudoref(struct ref_store *refs, const char *refname)
+{
+	static const char *const irregular_pseudorefs[] = {
+		"AUTO_MERGE",
+		"BISECT_EXPECTED_REV",
+		"NOTES_MERGE_PARTIAL",
+		"NOTES_MERGE_REF",
+		"MERGE_AUTOSTASH",
+	};
+	struct object_id oid;
+	size_t i;
+
+	if (!is_pseudoref_syntax(refname))
+		return 0;
+
+	if (ends_with(refname, "_HEAD")) {
+		refs_resolve_ref_unsafe(refs, refname,
+					RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+					&oid, NULL);
+		return !is_null_oid(&oid);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(irregular_pseudorefs); i++)
+		if (!strcmp(refname, irregular_pseudorefs[i])) {
+			refs_resolve_ref_unsafe(refs, refname,
+						RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+						&oid, NULL);
+			return !is_null_oid(&oid);
+		}
+
+	return 0;
+}
+
+int is_headref(struct ref_store *refs, const char *refname)
+{
+	if (!strcmp(refname, "HEAD"))
+		return refs_ref_exists(refs, refname);
+
+	return 0;
+}
+
 static int is_current_worktree_ref(const char *ref) {
 	return is_pseudoref_syntax(ref) || is_per_worktree_ref(ref);
 }
@@ -1039,55 +1080,40 @@ static int read_ref_at_ent(struct object_id *ooid, struct object_id *noid,
 			   const char *message, void *cb_data)
 {
 	struct read_ref_at_cb *cb = cb_data;
-	int reached_count;
 
 	cb->tz = tz;
 	cb->date = timestamp;
 
-	/*
-	 * It is not possible for cb->cnt == 0 on the first iteration because
-	 * that special case is handled in read_ref_at().
-	 */
-	if (cb->cnt > 0)
-		cb->cnt--;
-	reached_count = cb->cnt == 0 && !is_null_oid(ooid);
-	if (timestamp <= cb->at_time || reached_count) {
+	if (timestamp <= cb->at_time || cb->cnt == 0) {
 		set_read_ref_cutoffs(cb, timestamp, tz, message);
 		/*
 		 * we have not yet updated cb->[n|o]oid so they still
 		 * hold the values for the previous record.
 		 */
-		if (!is_null_oid(&cb->ooid) && !oideq(&cb->ooid, noid))
-			warning(_("log for ref %s has gap after %s"),
+		if (!is_null_oid(&cb->ooid)) {
+			oidcpy(cb->oid, noid);
+			if (!oideq(&cb->ooid, noid))
+				warning(_("log for ref %s has gap after %s"),
 					cb->refname, show_date(cb->date, cb->tz, DATE_MODE(RFC2822)));
-		if (reached_count)
-			oidcpy(cb->oid, ooid);
-		else if (!is_null_oid(&cb->ooid) || cb->date == cb->at_time)
+		}
+		else if (cb->date == cb->at_time)
 			oidcpy(cb->oid, noid);
 		else if (!oideq(noid, cb->oid))
 			warning(_("log for ref %s unexpectedly ended on %s"),
 				cb->refname, show_date(cb->date, cb->tz,
 						       DATE_MODE(RFC2822)));
+		cb->reccnt++;
+		oidcpy(&cb->ooid, ooid);
+		oidcpy(&cb->noid, noid);
 		cb->found_it = 1;
+		return 1;
 	}
 	cb->reccnt++;
 	oidcpy(&cb->ooid, ooid);
 	oidcpy(&cb->noid, noid);
-	return cb->found_it;
-}
-
-static int read_ref_at_ent_newest(struct object_id *ooid UNUSED,
-				  struct object_id *noid,
-				  const char *email UNUSED,
-				  timestamp_t timestamp, int tz,
-				  const char *message, void *cb_data)
-{
-	struct read_ref_at_cb *cb = cb_data;
-
-	set_read_ref_cutoffs(cb, timestamp, tz, message);
-	oidcpy(cb->oid, noid);
-	/* We just want the first entry */
-	return 1;
+	if (cb->cnt > 0)
+		cb->cnt--;
+	return 0;
 }
 
 static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid,
@@ -1099,7 +1125,7 @@ static int read_ref_at_ent_oldest(struct object_id *ooid, struct object_id *noid
 
 	set_read_ref_cutoffs(cb, timestamp, tz, message);
 	oidcpy(cb->oid, ooid);
-	if (is_null_oid(cb->oid))
+	if (cb->at_time && is_null_oid(cb->oid))
 		oidcpy(cb->oid, noid);
 	/* We just want the first entry */
 	return 1;
@@ -1122,14 +1148,24 @@ int read_ref_at(struct ref_store *refs, const char *refname,
 	cb.cutoff_cnt = cutoff_cnt;
 	cb.oid = oid;
 
-	if (cb.cnt == 0) {
-		refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent_newest, &cb);
-		return 0;
-	}
-
 	refs_for_each_reflog_ent_reverse(refs, refname, read_ref_at_ent, &cb);
 
 	if (!cb.reccnt) {
+		if (cnt == 0) {
+			/*
+			 * The caller asked for ref@{0}, and we had no entries.
+			 * It's a bit subtle, but in practice all callers have
+			 * prepped the "oid" field with the current value of
+			 * the ref, which is the most reasonable fallback.
+			 *
+			 * We'll put dummy values into the out-parameters (so
+			 * they're not just uninitialized garbage), and the
+			 * caller can take our return value as a hint that
+			 * we did not find any such reflog.
+			 */
+			set_read_ref_cutoffs(&cb, 0, 0, "empty reflog");
+			return 1;
+		}
 		if (flags & GET_OID_QUIETLY)
 			exit(128);
 		else
@@ -1720,6 +1756,13 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)
 	return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
 }
 
+int refs_for_each_include_root_refs(struct ref_store *refs, each_ref_fn fn,
+				    void *cb_data)
+{
+	return do_for_each_ref(refs, "", NULL, fn, 0,
+			       DO_FOR_EACH_INCLUDE_ROOT_REFS, cb_data);
+}
+
 static int qsort_strcmp(const void *va, const void *vb)
 {
 	const char *a = *(const char **)va;

diff --git a/refs.h b/refs.h
index 895579a..298caf6 100644
--- a/refs.h
+++ b/refs.h

@@ -399,6 +399,12 @@ int refs_for_each_rawref(struct ref_store *refs, each_ref_fn fn, void *cb_data);
 int for_each_rawref(each_ref_fn fn, void *cb_data);
 
 /*
+ * Iterates over all refs including root refs, i.e. pseudorefs and HEAD.
+ */
+int refs_for_each_include_root_refs(struct ref_store *refs, each_ref_fn fn,
+				    void *cb_data);
+
+/*
  * Normalizes partial refs to their fully qualified form.
  * Will prepend <prefix> to the <pattern> if it doesn't start with 'refs/'.
  * <prefix> will default to 'refs/' if NULL.
@@ -440,7 +446,20 @@ int refs_create_reflog(struct ref_store *refs, const char *refname,
 		       struct strbuf *err);
 int safe_create_reflog(const char *refname, struct strbuf *err);
 
-/** Reads log for the value of ref during at_time. **/
+/**
+ * Reads log for the value of ref during at_time (in which case "cnt" should be
+ * negative) or the reflog "cnt" entries from the top (in which case "at_time"
+ * should be 0).
+ *
+ * If we found the reflog entry in question, returns 0 (and details of the
+ * entry can be found in the out-parameters).
+ *
+ * If we ran out of reflog entries, the out-parameters are filled with the
+ * details of the oldest entry we did find, and the function returns 1. Note
+ * that there is one important special case here! If the reflog was empty
+ * and the caller asked for the 0-th cnt, we will return "1" but leave the
+ * "oid" field untouched.
+ **/
 int read_ref_at(struct ref_store *refs,
 		const char *refname, unsigned int flags,
 		timestamp_t at_time, int cnt,
@@ -1030,4 +1049,7 @@ extern struct ref_namespace_info ref_namespace[NAMESPACE__COUNT];
  */
 void update_ref_namespace(enum ref_namespace namespace, char *ref);
 
+int is_pseudoref(struct ref_store *refs, const char *refname);
+int is_headref(struct ref_store *refs, const char *refname);
+
 #endif /* REFS_H */

diff --git a/refs/files-backend.c b/refs/files-backend.c
index 6f98168..a098d14 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c

@@ -229,6 +229,38 @@ static void add_per_worktree_entries_to_dir(struct ref_dir *dir, const char *dir
 	}
 }
 
+static void loose_fill_ref_dir_regular_file(struct files_ref_store *refs,
+					    const char *refname,
+					    struct ref_dir *dir)
+{
+	struct object_id oid;
+	int flag;
+
+	if (!refs_resolve_ref_unsafe(&refs->base, refname, RESOLVE_REF_READING,
+				     &oid, &flag)) {
+		oidclr(&oid);
+		flag |= REF_ISBROKEN;
+	} else if (is_null_oid(&oid)) {
+		/*
+		 * It is so astronomically unlikely
+		 * that null_oid is the OID of an
+		 * actual object that we consider its
+		 * appearance in a loose reference
+		 * file to be repo corruption
+		 * (probably due to a software bug).
+		 */
+		flag |= REF_ISBROKEN;
+	}
+
+	if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
+		if (!refname_is_safe(refname))
+			die("loose refname is dangerous: %s", refname);
+		oidclr(&oid);
+		flag |= REF_BAD_NAME | REF_ISBROKEN;
+	}
+	add_entry_to_dir(dir, create_ref_entry(refname, &oid, flag));
+}
+
 /*
  * Read the loose references from the namespace dirname into dir
  * (without recursing).  dirname must end with '/'.  dir must be the
@@ -257,8 +289,6 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
 	strbuf_add(&refname, dirname, dirnamelen);
 
 	while ((de = readdir(d)) != NULL) {
-		struct object_id oid;
-		int flag;
 		unsigned char dtype;
 
 		if (de->d_name[0] == '.')
@@ -274,33 +304,7 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
 					 create_dir_entry(dir->cache, refname.buf,
 							  refname.len));
 		} else if (dtype == DT_REG) {
-			if (!refs_resolve_ref_unsafe(&refs->base,
-						     refname.buf,
-						     RESOLVE_REF_READING,
-						     &oid, &flag)) {
-				oidclr(&oid);
-				flag |= REF_ISBROKEN;
-			} else if (is_null_oid(&oid)) {
-				/*
-				 * It is so astronomically unlikely
-				 * that null_oid is the OID of an
-				 * actual object that we consider its
-				 * appearance in a loose reference
-				 * file to be repo corruption
-				 * (probably due to a software bug).
-				 */
-				flag |= REF_ISBROKEN;
-			}
-
-			if (check_refname_format(refname.buf,
-						 REFNAME_ALLOW_ONELEVEL)) {
-				if (!refname_is_safe(refname.buf))
-					die("loose refname is dangerous: %s", refname.buf);
-				oidclr(&oid);
-				flag |= REF_BAD_NAME | REF_ISBROKEN;
-			}
-			add_entry_to_dir(dir,
-					 create_ref_entry(refname.buf, &oid, flag));
+			loose_fill_ref_dir_regular_file(refs, refname.buf, dir);
 		}
 		strbuf_setlen(&refname, dirnamelen);
 	}
@@ -311,9 +315,59 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
 	add_per_worktree_entries_to_dir(dir, dirname);
 }
 
-static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs)
+/*
+ * Add pseudorefs to the ref dir by parsing the directory for any files
+ * which follow the pseudoref syntax.
+ */
+static void add_pseudoref_and_head_entries(struct ref_store *ref_store,
+					 struct ref_dir *dir,
+					 const char *dirname)
+{
+	struct files_ref_store *refs =
+		files_downcast(ref_store, REF_STORE_READ, "fill_ref_dir");
+	struct strbuf path = STRBUF_INIT, refname = STRBUF_INIT;
+	struct dirent *de;
+	size_t dirnamelen;
+	DIR *d;
+
+	files_ref_path(refs, &path, dirname);
+
+	d = opendir(path.buf);
+	if (!d) {
+		strbuf_release(&path);
+		return;
+	}
+
+	strbuf_addstr(&refname, dirname);
+	dirnamelen = refname.len;
+
+	while ((de = readdir(d)) != NULL) {
+		unsigned char dtype;
+
+		if (de->d_name[0] == '.')
+			continue;
+		if (ends_with(de->d_name, ".lock"))
+			continue;
+		strbuf_addstr(&refname, de->d_name);
+
+		dtype = get_dtype(de, &path, 1);
+		if (dtype == DT_REG && (is_pseudoref(ref_store, de->d_name) ||
+								is_headref(ref_store, de->d_name)))
+			loose_fill_ref_dir_regular_file(refs, refname.buf, dir);
+
+		strbuf_setlen(&refname, dirnamelen);
+	}
+	strbuf_release(&refname);
+	strbuf_release(&path);
+	closedir(d);
+}
+
+static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs,
+					     unsigned int flags)
 {
 	if (!refs->loose) {
+		struct ref_dir *dir;
+
 		/*
 		 * Mark the top-level directory complete because we
 		 * are about to read the only subdirectory that can
@@ -324,12 +378,17 @@ static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs)
 		/* We're going to fill the top level ourselves: */
 		refs->loose->root->flag &= ~REF_INCOMPLETE;
 
+		dir = get_ref_dir(refs->loose->root);
+
+		if (flags & DO_FOR_EACH_INCLUDE_ROOT_REFS)
+			add_pseudoref_and_head_entries(dir->cache->ref_store, dir,
+						       refs->loose->root->name);
+
 		/*
 		 * Add an incomplete entry for "refs/" (to be filled
 		 * lazily):
 		 */
-		add_entry_to_dir(get_ref_dir(refs->loose->root),
-				 create_dir_entry(refs->loose, "refs/", 5));
+		add_entry_to_dir(dir, create_dir_entry(refs->loose, "refs/", 5));
 	}
 	return refs->loose;
 }
@@ -857,7 +916,7 @@ static struct ref_iterator *files_ref_iterator_begin(
 	 * disk, and re-reads it if not.
 	 */
 
-	loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs),
+	loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, flags),
 					      prefix, ref_store->repo, 1);
 
 	/*
@@ -1217,7 +1276,7 @@ static int files_pack_refs(struct ref_store *ref_store,
 
 	packed_refs_lock(refs->packed_ref_store, LOCK_DIE_ON_ERROR, &err);
 
-	iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), NULL,
+	iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, 0), NULL,
 					the_repository, 0);
 	while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
 		/*

diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index a9b6e88..56641aa 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h

@@ -260,6 +260,12 @@ enum do_for_each_ref_flags {
 	 * INCLUDE_BROKEN, since they are otherwise not included at all.
 	 */
 	DO_FOR_EACH_OMIT_DANGLING_SYMREFS = (1 << 2),
+
+	/*
+	 * Include root refs i.e. HEAD and pseudorefs along with the regular
+	 * refs.
+	 */
+	DO_FOR_EACH_INCLUDE_ROOT_REFS = (1 << 3),
 };
 
 /*

diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index 6c11c4a..2c88bbd 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c

@@ -364,12 +364,15 @@ static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator)
 			break;
 
 		/*
-		 * The files backend only lists references contained in
-		 * "refs/". We emulate the same behaviour here and thus skip
-		 * all references that don't start with this prefix.
+		 * The files backend only lists references contained in "refs/" unless
+		 * the root refs are to be included. We emulate the same behaviour here.
 		 */
-		if (!starts_with(iter->ref.refname, "refs/"))
+		if (!starts_with(iter->ref.refname, "refs/") &&
+		    !(iter->flags & DO_FOR_EACH_INCLUDE_ROOT_REFS &&
+		     (is_pseudoref(&iter->refs->base, iter->ref.refname) ||
+		      is_headref(&iter->refs->base, iter->ref.refname)))) {
 			continue;
+		}
 
 		if (iter->prefix &&
 		    strncmp(iter->prefix, iter->ref.refname, strlen(iter->prefix))) {
@@ -778,6 +781,7 @@ static int reftable_be_transaction_prepare(struct ref_store *ref_store,
 				      &head_referent, &head_type);
 	if (ret < 0)
 		goto done;
+	ret = 0;
 
 	for (i = 0; i < transaction->nr; i++) {
 		struct ref_update *u = transaction->updates[i];

diff --git a/remote.c b/remote.c
index 9090632..2b650b8 100644
--- a/remote.c
+++ b/remote.c

@@ -2679,7 +2679,7 @@ static int is_reachable_in_reflog(const char *local, const struct ref *remote)
 		if (MERGE_BASES_BATCH_SIZE < size)
 			size = MERGE_BASES_BATCH_SIZE;
 
-		if ((ret = repo_in_merge_bases_many(the_repository, commit, size, chunk)))
+		if ((ret = repo_in_merge_bases_many(the_repository, commit, size, chunk, 0)))
 			break;
 	}
 

diff --git a/reset.c b/reset.c
index 0f2ff0f..d619cb7 100644
--- a/reset.c
+++ b/reset.c

@@ -157,6 +157,11 @@ int reset_head(struct repository *r, const struct reset_head_opts *opts)
 	}
 
 	tree = parse_tree_indirect(oid);
+	if (!tree) {
+		ret = error(_("unable to read tree (%s)"), oid_to_hex(oid));
+		goto leave_reset_head;
+	}
+
 	prime_cache_tree(r, r->index, tree);
 
 	if (write_locked_index(r->index, &lock, COMMIT_LOCK) < 0) {

diff --git a/revision.c b/revision.c
index ac45c6d..4589365 100644
--- a/revision.c
+++ b/revision.c

@@ -381,13 +381,18 @@ static struct object *get_reference(struct rev_info *revs, const char *name,
 
 	object = parse_object_with_flags(revs->repo, oid,
 					 revs->verify_objects ? 0 :
-					 PARSE_OBJECT_SKIP_HASH_CHECK);
+					 PARSE_OBJECT_SKIP_HASH_CHECK |
+					 PARSE_OBJECT_DISCARD_TREE);
 
 	if (!object) {
 		if (revs->ignore_missing)
-			return object;
+			return NULL;
 		if (revs->exclude_promisor_objects && is_promisor_object(oid))
 			return NULL;
+		if (revs->do_not_die_on_missing_objects) {
+			oidset_insert(&revs->missing_commits, oid);
+			return NULL;
+		}
 		die("bad object %s", name);
 	}
 	object->flags |= flags;
@@ -415,15 +420,21 @@ static struct commit *handle_commit(struct rev_info *revs,
 	 */
 	while (object->type == OBJ_TAG) {
 		struct tag *tag = (struct tag *) object;
+		struct object_id *oid;
 		if (revs->tag_objects && !(flags & UNINTERESTING))
 			add_pending_object(revs, object, tag->tag);
-		object = parse_object(revs->repo, get_tagged_oid(tag));
+		oid = get_tagged_oid(tag);
+		object = parse_object(revs->repo, oid);
 		if (!object) {
 			if (revs->ignore_missing_links || (flags & UNINTERESTING))
 				return NULL;
 			if (revs->exclude_promisor_objects &&
 			    is_promisor_object(&tag->tagged->oid))
 				return NULL;
+			if (revs->do_not_die_on_missing_objects && oid) {
+				oidset_insert(&revs->missing_commits, oid);
+				return NULL;
+			}
 			die("bad object %s", oid_to_hex(&tag->tagged->oid));
 		}
 		object->flags |= flags;
@@ -1945,6 +1956,7 @@ void repo_init_revisions(struct repository *r,
 	init_display_notes(&revs->notes_opt);
 	list_objects_filter_init(&revs->filter);
 	init_ref_exclusions(&revs->ref_excludes);
+	oidset_init(&revs->missing_commits, 0);
 }
 
 static void add_pending_commit_list(struct rev_info *revs,
@@ -1959,11 +1971,31 @@ static void add_pending_commit_list(struct rev_info *revs,
 	}
 }
 
+static const char *lookup_other_head(struct object_id *oid)
+{
+	int i;
+	static const char *const other_head[] = {
+		"MERGE_HEAD", "CHERRY_PICK_HEAD", "REVERT_HEAD", "REBASE_HEAD"
+	};
+
+	for (i = 0; i < ARRAY_SIZE(other_head); i++)
+		if (!read_ref_full(other_head[i],
+				RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+				oid, NULL)) {
+			if (is_null_oid(oid))
+				die(_("%s exists but is a symbolic ref"), other_head[i]);
+			return other_head[i];
+		}
+
+	die(_("--merge requires one of the pseudorefs MERGE_HEAD, CHERRY_PICK_HEAD, REVERT_HEAD or REBASE_HEAD"));
+}
+
 static void prepare_show_merge(struct rev_info *revs)
 {
-	struct commit_list *bases;
+	struct commit_list *bases = NULL;
 	struct commit *head, *other;
 	struct object_id oid;
+	const char *other_name;
 	const char **prune = NULL;
 	int i, prune_num = 1; /* counting terminating NULL */
 	struct index_state *istate = revs->repo->index;
@@ -1971,12 +2003,12 @@ static void prepare_show_merge(struct rev_info *revs)
 	if (repo_get_oid(the_repository, "HEAD", &oid))
 		die("--merge without HEAD?");
 	head = lookup_commit_or_die(&oid, "HEAD");
-	if (repo_get_oid(the_repository, "MERGE_HEAD", &oid))
-		die("--merge without MERGE_HEAD?");
-	other = lookup_commit_or_die(&oid, "MERGE_HEAD");
+	other_name = lookup_other_head(&oid);
+	other = lookup_commit_or_die(&oid, other_name);
 	add_pending_object(revs, &head->object, "HEAD");
-	add_pending_object(revs, &other->object, "MERGE_HEAD");
-	bases = repo_get_merge_bases(the_repository, head, other);
+	add_pending_object(revs, &other->object, other_name);
+	if (repo_get_merge_bases(the_repository, head, other, &bases) < 0)
+		exit(128);
 	add_rev_cmdline_list(revs, bases, REV_CMD_MERGE_BASE, UNINTERESTING | BOTTOM);
 	add_pending_commit_list(revs, bases, UNINTERESTING | BOTTOM);
 	free_commit_list(bases);
@@ -2064,14 +2096,17 @@ static int handle_dotdot_1(const char *arg, char *dotdot,
 	} else {
 		/* A...B -- find merge bases between the two */
 		struct commit *a, *b;
-		struct commit_list *exclude;
+		struct commit_list *exclude = NULL;
 
 		a = lookup_commit_reference(revs->repo, &a_obj->oid);
 		b = lookup_commit_reference(revs->repo, &b_obj->oid);
 		if (!a || !b)
 			return dotdot_missing(arg, dotdot, revs, symmetric);
 
-		exclude = repo_get_merge_bases(the_repository, a, b);
+		if (repo_get_merge_bases(the_repository, a, b, &exclude) < 0) {
+			free_commit_list(exclude);
+			return -1;
+		}
 		add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
 				     flags_exclude);
 		add_pending_commit_list(revs, exclude, flags_exclude);
@@ -2176,13 +2211,18 @@ static int handle_revision_arg_1(const char *arg_, struct rev_info *revs, int fl
 	if (revarg_opt & REVARG_COMMITTISH)
 		get_sha1_flags |= GET_OID_COMMITTISH;
 
+	/*
+	 * Even if revs->do_not_die_on_missing_objects is set, we
+	 * should error out if we can't even get an oid, as
+	 * `--missing=print` should be able to report missing oids.
+	 */
 	if (get_oid_with_context(revs->repo, arg, get_sha1_flags, &oid, &oc))
 		return revs->ignore_missing ? 0 : -1;
 	if (!cant_be_filename)
 		verify_non_filename(revs->prefix, arg);
 	object = get_reference(revs, arg, &oid, flags ^ local_flags);
 	if (!object)
-		return revs->ignore_missing ? 0 : -1;
+		return (revs->ignore_missing || revs->do_not_die_on_missing_objects) ? 0 : -1;
 	add_rev_cmdline(revs, object, arg_, REV_CMD_REV, flags ^ local_flags);
 	add_pending_object_with_path(revs, object, arg, oc.mode, oc.path);
 	free(oc.path);
@@ -3828,8 +3868,6 @@ int prepare_revision_walk(struct rev_info *revs)
 				       FOR_EACH_OBJECT_PROMISOR_ONLY);
 	}
 
-	oidset_init(&revs->missing_commits, 0);
-
 	if (!revs->reflog_info)
 		prepare_to_use_bloom_filter(revs);
 	if (!revs->unsorted_input)

diff --git a/sequencer.c b/sequencer.c
index f49a871..5c6f541 100644
--- a/sequencer.c
+++ b/sequencer.c

@@ -707,6 +707,8 @@ static int do_recursive_merge(struct repository *r,
 	o.show_rename_progress = 1;
 
 	head_tree = parse_tree_indirect(head);
+	if (!head_tree)
+		return error(_("unable to read tree (%s)"), oid_to_hex(head));
 	next_tree = next ? repo_get_commit_tree(r, next) : empty_tree(r);
 	base_tree = base ? repo_get_commit_tree(r, base) : empty_tree(r);
 
@@ -3882,6 +3884,8 @@ static int do_reset(struct repository *r,
 	}
 
 	tree = parse_tree_indirect(&oid);
+	if (!tree)
+		return error(_("unable to read tree (%s)"), oid_to_hex(&oid));
 	prime_cache_tree(r, r->index, tree);
 
 	if (write_locked_index(r->index, &lock, COMMIT_LOCK) < 0)
@@ -3908,7 +3912,7 @@ static int do_merge(struct repository *r,
 	int run_commit_flags = 0;
 	struct strbuf ref_name = STRBUF_INIT;
 	struct commit *head_commit, *merge_commit, *i;
-	struct commit_list *bases, *j;
+	struct commit_list *bases = NULL, *j;
 	struct commit_list *to_merge = NULL, **tail = &to_merge;
 	const char *strategy = !opts->xopts.nr &&
 		(!opts->strategy ||
@@ -4134,7 +4138,11 @@ static int do_merge(struct repository *r,
 	}
 
 	merge_commit = to_merge->item;
-	bases = repo_get_merge_bases(r, head_commit, merge_commit);
+	if (repo_get_merge_bases(r, head_commit, merge_commit, &bases) < 0) {
+		ret = -1;
+		goto leave_merge;
+	}
+
 	if (bases && oideq(&merge_commit->object.oid,
 			   &bases->item->object.oid)) {
 		ret = 0;

diff --git a/serve.c b/serve.c
index a1d7113..aa651b7 100644
--- a/serve.c
+++ b/serve.c

@@ -12,6 +12,7 @@
 #include "trace2.h"
 
 static int advertise_sid = -1;
+static int advertise_object_info = -1;
 static int client_hash_algo = GIT_HASH_SHA1;
 
 static int always_advertise(struct repository *r UNUSED,
@@ -67,6 +68,17 @@ static void session_id_receive(struct repository *r UNUSED,
 	trace2_data_string("transfer", NULL, "client-sid", client_sid);
 }
 
+static int object_info_advertise(struct repository *r, struct strbuf *value UNUSED)
+{
+	if (advertise_object_info == -1 &&
+	    repo_config_get_bool(r, "transfer.advertiseobjectinfo",
+				 &advertise_object_info)) {
+		/* disabled by default */
+		advertise_object_info = 0;
+	}
+	return advertise_object_info;
+}
+
 struct protocol_capability {
 	/*
 	 * The name of the capability.  The server uses this name when
@@ -135,7 +147,7 @@ static struct protocol_capability capabilities[] = {
 	},
 	{
 		.name = "object-info",
-		.advertise = always_advertise,
+		.advertise = object_info_advertise,
 		.command = cap_object_info,
 	},
 	{

diff --git a/setup.c b/setup.c
index b69b1cb..e3b76e8 100644
--- a/setup.c
+++ b/setup.c

@@ -1889,6 +1889,13 @@ void initialize_repository_version(int hash_algo,
 	char repo_version_string[10];
 	int repo_version = GIT_REPO_VERSION;
 
+	/*
+	 * Note that we initialize the repository version to 1 when the ref
+	 * storage format is unknown. This is on purpose so that we can add the
+	 * correct object format to the config during git-clone(1). The format
+	 * version will get adjusted by git-clone(1) once it has learned about
+	 * the remote repository's format.
+	 */
 	if (hash_algo != GIT_HASH_SHA1 ||
 	    ref_storage_format != REF_STORAGE_FORMAT_FILES)
 		repo_version = GIT_REPO_VERSION_READ;
@@ -1898,7 +1905,7 @@ void initialize_repository_version(int hash_algo,
 		  "%d", repo_version);
 	git_config_set("core.repositoryformatversion", repo_version_string);
 
-	if (hash_algo != GIT_HASH_SHA1)
+	if (hash_algo != GIT_HASH_SHA1 && hash_algo != GIT_HASH_UNKNOWN)
 		git_config_set("extensions.objectformat",
 			       hash_algos[hash_algo].name);
 	else if (reinit)

diff --git a/shallow.c b/shallow.c
index 7711798..7ff50dd 100644
--- a/shallow.c
+++ b/shallow.c

@@ -794,12 +794,16 @@ static void post_assign_shallow(struct shallow_info *info,
 		if (!*bitmap)
 			continue;
 		for (j = 0; j < bitmap_nr; j++)
-			if (bitmap[0][j] &&
-			    /* Step 7, reachability test at commit level */
-			    !repo_in_merge_bases_many(the_repository, c, ca.nr, ca.commits)) {
-				update_refstatus(ref_status, info->ref->nr, *bitmap);
-				dst++;
-				break;
+			if (bitmap[0][j]) {
+				/* Step 7, reachability test at commit level */
+				int ret = repo_in_merge_bases_many(the_repository, c, ca.nr, ca.commits, 1);
+				if (ret < 0)
+					exit(128);
+				if (!ret) {
+					update_refstatus(ref_status, info->ref->nr, *bitmap);
+					dst++;
+					break;
+				}
 			}
 	}
 	info->nr_ours = dst;
@@ -827,7 +831,10 @@ int delayed_reachability_test(struct shallow_info *si, int c)
 		si->reachable[c] = repo_in_merge_bases_many(the_repository,
 							    commit,
 							    si->nr_commits,
-							    si->commits);
+							    si->commits,
+							    1);
+		if (si->reachable[c] < 0)
+			exit(128);
 		si->need_reachability_test[c] = 0;
 	}
 	return si->reachable[c];

diff --git a/submodule.c b/submodule.c
index 213da79..f0ddb31 100644
--- a/submodule.c
+++ b/submodule.c

@@ -592,7 +592,12 @@ static void show_submodule_header(struct diff_options *o,
 	     (!is_null_oid(two) && !*right))
 		message = "(commits not present)";
 
-	*merge_bases = repo_get_merge_bases(sub, *left, *right);
+	*merge_bases = NULL;
+	if (repo_get_merge_bases(sub, *left, *right, merge_bases) < 0) {
+		message = "(corrupt repository)";
+		goto output_header;
+	}
+
 	if (*merge_bases) {
 		if ((*merge_bases)->item == *left)
 			fast_forward = 1;
@@ -1687,8 +1692,6 @@ static int get_next_submodule(struct child_process *cp, struct strbuf *err,
 		task = get_fetch_task_from_changed(spf, err);
 
 	if (task) {
-		struct strbuf submodule_prefix = STRBUF_INIT;
-
 		child_process_init(cp);
 		cp->dir = task->repo->gitdir;
 		prepare_submodule_repo_env_in_gitdir(&cp->env);
@@ -1698,15 +1701,11 @@ static int get_next_submodule(struct child_process *cp, struct strbuf *err,
 			strvec_pushv(&cp->args, task->git_args.v);
 		strvec_pushv(&cp->args, spf->args.v);
 		strvec_push(&cp->args, task->default_argv);
-		strvec_push(&cp->args, "--submodule-prefix");
+		strvec_pushf(&cp->args, "--submodule-prefix=%s%s/",
+			     spf->prefix, task->sub->path);
 
-		strbuf_addf(&submodule_prefix, "%s%s/",
-						spf->prefix,
-						task->sub->path);
-		strvec_push(&cp->args, submodule_prefix.buf);
 		*task_cb = task;
 
-		strbuf_release(&submodule_prefix);
 		string_list_insert(&spf->seen_submodule_names, task->sub->name);
 		return 1;
 	}
@@ -1714,12 +1713,8 @@ static int get_next_submodule(struct child_process *cp, struct strbuf *err,
 	if (spf->oid_fetch_tasks_nr) {
 		struct fetch_task *task =
 			spf->oid_fetch_tasks[spf->oid_fetch_tasks_nr - 1];
-		struct strbuf submodule_prefix = STRBUF_INIT;
 		spf->oid_fetch_tasks_nr--;
 
-		strbuf_addf(&submodule_prefix, "%s%s/",
-			    spf->prefix, task->sub->path);
-
 		child_process_init(cp);
 		prepare_submodule_repo_env_in_gitdir(&cp->env);
 		cp->git_cmd = 1;
@@ -1728,8 +1723,8 @@ static int get_next_submodule(struct child_process *cp, struct strbuf *err,
 		strvec_init(&cp->args);
 		strvec_pushv(&cp->args, spf->args.v);
 		strvec_push(&cp->args, "on-demand");
-		strvec_push(&cp->args, "--submodule-prefix");
-		strvec_push(&cp->args, submodule_prefix.buf);
+		strvec_pushf(&cp->args, "--submodule-prefix=%s%s/",
+			     spf->prefix, task->sub->path);
 
 		/* NEEDSWORK: have get_default_remote from submodule--helper */
 		strvec_push(&cp->args, "origin");
@@ -1737,7 +1732,6 @@ static int get_next_submodule(struct child_process *cp, struct strbuf *err,
 					  append_oid_to_argv, &cp->args);
 
 		*task_cb = task;
-		strbuf_release(&submodule_prefix);
 		return 1;
 	}
 

diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c
index 1e159a7..1e3b431 100644
--- a/t/helper/test-reach.c
+++ b/t/helper/test-reach.c

@@ -111,13 +111,16 @@ int cmd__reach(int ac, const char **av)
 		       repo_in_merge_bases(the_repository, A, B));
 	else if (!strcmp(av[1], "in_merge_bases_many"))
 		printf("%s(A,X):%d\n", av[1],
-		       repo_in_merge_bases_many(the_repository, A, X_nr, X_array));
+		       repo_in_merge_bases_many(the_repository, A, X_nr, X_array, 0));
 	else if (!strcmp(av[1], "is_descendant_of"))
 		printf("%s(A,X):%d\n", av[1], repo_is_descendant_of(r, A, X));
 	else if (!strcmp(av[1], "get_merge_bases_many")) {
-		struct commit_list *list = repo_get_merge_bases_many(the_repository,
-								     A, X_nr,
-								     X_array);
+		struct commit_list *list = NULL;
+		if (repo_get_merge_bases_many(the_repository,
+					      A, X_nr,
+					      X_array,
+					      &list) < 0)
+			exit(128);
 		printf("%s(A,X):\n", av[1]);
 		print_sorted_commit_ids(list);
 	} else if (!strcmp(av[1], "reduce_heads")) {

diff --git a/t/t0410-partial-clone.sh b/t/t0410-partial-clone.sh
index 0f98b21..88a66f0 100755
--- a/t/t0410-partial-clone.sh
+++ b/t/t0410-partial-clone.sh

@@ -665,6 +665,21 @@
 	git -C partial.git rev-list --objects --missing=print HEAD >out &&
 	grep "[?]$FILE_HASH" out &&
 
+	# The no-lazy-fetch mechanism prevents Git from fetching
+	test_must_fail env GIT_NO_LAZY_FETCH=1 \
+		git -C partial.git cat-file -e "$FILE_HASH" &&
+
+	# The same with command line option to "git"
+	test_must_fail git --no-lazy-fetch -C partial.git cat-file -e "$FILE_HASH" &&
+
+	# The same, forcing a subprocess via an alias
+	test_must_fail git --no-lazy-fetch -C partial.git \
+		-c alias.foo="!git cat-file" foo -e "$FILE_HASH" &&
+
+	# Sanity check that the file is still missing
+	git -C partial.git rev-list --objects --missing=print HEAD >out &&
+	grep "[?]$FILE_HASH" out &&
+
 	git -C full cat-file -s "$FILE_HASH" >expect &&
 	test-tool partial-clone object-info partial.git "$FILE_HASH" >actual &&
 	test_cmp expect actual &&

diff --git a/t/t0600-reffiles-backend.sh b/t/t0600-reffiles-backend.sh
index 09e71b2..6421434 100755
--- a/t/t0600-reffiles-backend.sh
+++ b/t/t0600-reffiles-backend.sh

@@ -279,18 +279,18 @@
 # direct FS access for creating the reflogs. 3) PSEUDO-WT and refs/bisect/random
 # do not create reflogs by default, so it is not testing a realistic scenario.
 test_expect_success 'for_each_reflog()' '
-	echo $ZERO_OID > .git/logs/PSEUDO-MAIN &&
+	echo $ZERO_OID >.git/logs/PSEUDO_MAIN_HEAD &&
 	mkdir -p     .git/logs/refs/bisect &&
-	echo $ZERO_OID > .git/logs/refs/bisect/random &&
+	echo $ZERO_OID >.git/logs/refs/bisect/random &&
 
-	echo $ZERO_OID > .git/worktrees/wt/logs/PSEUDO-WT &&
+	echo $ZERO_OID >.git/worktrees/wt/logs/PSEUDO_WT_HEAD &&
 	mkdir -p     .git/worktrees/wt/logs/refs/bisect &&
-	echo $ZERO_OID > .git/worktrees/wt/logs/refs/bisect/wt-random &&
+	echo $ZERO_OID >.git/worktrees/wt/logs/refs/bisect/wt-random &&
 
 	$RWT for-each-reflog >actual &&
 	cat >expected <<-\EOF &&
 	HEAD
-	PSEUDO-WT
+	PSEUDO_WT_HEAD
 	refs/bisect/wt-random
 	refs/heads/main
 	refs/heads/wt-main
@@ -300,7 +300,7 @@
 	$RMAIN for-each-reflog >actual &&
 	cat >expected <<-\EOF &&
 	HEAD
-	PSEUDO-MAIN
+	PSEUDO_MAIN_HEAD
 	refs/bisect/random
 	refs/heads/main
 	refs/heads/wt-main

diff --git a/t/t0610-reftable-basics.sh b/t/t0610-reftable-basics.sh
index 6a131e4..6867811 100755
--- a/t/t0610-reftable-basics.sh
+++ b/t/t0610-reftable-basics.sh

@@ -328,6 +328,18 @@
 	EOF
 '
 
+test_expect_success 'ref transaction: empty transaction in empty repo' '
+	test_when_finished "rm -rf repo" &&
+	git init repo &&
+	test_commit -C repo --no-tag A &&
+	git -C repo update-ref -d refs/heads/main &&
+	test-tool -C repo ref-store main delete-refs REF_NO_DEREF msg HEAD &&
+	git -C repo update-ref --stdin <<-EOF
+	prepare
+	commit
+	EOF
+'
+
 test_expect_success 'pack-refs: compacts tables' '
 	test_when_finished "rm -rf repo" &&
 	git init repo &&

diff --git a/t/t3202-show-branch.sh b/t/t3202-show-branch.sh
index 6a98b2d..a1139f7 100755
--- a/t/t3202-show-branch.sh
+++ b/t/t3202-show-branch.sh

@@ -4,9 +4,6 @@
 
 . ./test-lib.sh
 
-# arbitrary reference time: 2009-08-30 19:20:00
-GIT_TEST_DATE_NOW=1251660000; export GIT_TEST_DATE_NOW
-
 test_expect_success 'error descriptions on empty repository' '
 	current=$(git branch --show-current) &&
 	cat >expect <<-EOF &&
@@ -187,18 +184,6 @@
 	test_cmp expect actual
 '
 
-test_expect_success 'show branch --reflog=2' '
-	sed "s/^>	//" >expect <<-\EOF &&
-	>	! [refs/heads/branch10@{0}] (4 years, 5 months ago) commit: branch10
-	>	 ! [refs/heads/branch10@{1}] (4 years, 5 months ago) commit: branch10
-	>	--
-	>	+  [refs/heads/branch10@{0}] branch10
-	>	++ [refs/heads/branch10@{1}] initial
-	EOF
-	git show-branch --reflog=2 >actual &&
-	test_cmp actual expect
-'
-
 # incompatible options
 while read combo
 do
@@ -264,4 +249,38 @@
 	test_branch_op_in_wt -c new-branch
 '
 
+test_expect_success 'setup reflogs' '
+	test_commit base &&
+	git checkout -b branch &&
+	test_commit one &&
+	git reset --hard HEAD^ &&
+	test_commit two &&
+	test_commit three
+'
+
+test_expect_success '--reflog shows reflog entries' '
+	cat >expect <<-\EOF &&
+	! [branch@{0}] (0 seconds ago) commit: three
+	 ! [branch@{1}] (60 seconds ago) commit: two
+	  ! [branch@{2}] (2 minutes ago) reset: moving to HEAD^
+	   ! [branch@{3}] (2 minutes ago) commit: one
+	----
+	+    [branch@{0}] three
+	++   [branch@{1}] two
+	   + [branch@{3}] one
+	++++ [branch@{2}] base
+	EOF
+	# the output always contains relative timestamps; use
+	# a known time to get deterministic results
+	GIT_TEST_DATE_NOW=$test_tick \
+	git show-branch --reflog branch >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--reflog handles missing reflog' '
+	git reflog expire --expire=now branch &&
+	git show-branch --reflog branch >actual &&
+	test_must_be_empty actual
+'
+
 test_done

diff --git a/t/t4042-diff-textconv-caching.sh b/t/t4042-diff-textconv-caching.sh
index bf33aed..8ebfa3c 100755
--- a/t/t4042-diff-textconv-caching.sh
+++ b/t/t4042-diff-textconv-caching.sh

@@ -118,4 +118,26 @@
 	git log --no-walk -p refs/notes/textconv/magic HEAD
 '
 
+test_expect_success 'caching is silently ignored outside repo' '
+	mkdir -p non-repo &&
+	echo one >non-repo/one &&
+	echo two >non-repo/two &&
+	echo "* diff=test" >attr &&
+	test_expect_code 1 \
+	nongit git -c core.attributesFile="$PWD/attr" \
+		   -c diff.test.textconv="tr a-z A-Z <" \
+		   -c diff.test.cachetextconv=true \
+		   diff --no-index one two >actual &&
+	cat >expect <<-\EOF &&
+	diff --git a/one b/two
+	index 5626abf..f719efd 100644
+	--- a/one
+	+++ b/two
+	@@ -1 +1 @@
+	-ONE
+	+TWO
+	EOF
+	test_cmp expect actual
+'
+
 test_done

diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh
index 12ac436..29e9974 100755
--- a/t/t4301-merge-tree-write-tree.sh
+++ b/t/t4301-merge-tree-write-tree.sh

@@ -945,4 +945,49 @@
 	test_cmp expect actual
 '
 
+test_expect_success '--merge-base with tree OIDs' '
+	git merge-tree --merge-base=side1^ side1 side3 >with-commits &&
+	git merge-tree --merge-base=side1^^{tree} side1^{tree} side3^{tree} >with-trees &&
+	test_cmp with-commits with-trees
+'
+
+test_expect_success 'error out on missing tree objects' '
+	git init --bare missing-tree.git &&
+	git rev-list side3 >list &&
+	git rev-parse side3^: >>list &&
+	git pack-objects missing-tree.git/objects/pack/side3-tree-is-missing <list &&
+	side3=$(git rev-parse side3) &&
+	test_must_fail git --git-dir=missing-tree.git merge-tree $side3^ $side3 >actual 2>err &&
+	test_grep "Could not read $(git rev-parse $side3:)" err &&
+	test_must_be_empty actual
+'
+
+test_expect_success 'error out on missing blob objects' '
+	echo 1 | git hash-object -w --stdin >blob1 &&
+	echo 2 | git hash-object -w --stdin >blob2 &&
+	echo 3 | git hash-object -w --stdin >blob3 &&
+	printf "100644 blob $(cat blob1)\tblob\n" | git mktree >tree1 &&
+	printf "100644 blob $(cat blob2)\tblob\n" | git mktree >tree2 &&
+	printf "100644 blob $(cat blob3)\tblob\n" | git mktree >tree3 &&
+	git init --bare missing-blob.git &&
+	cat blob1 blob3 tree1 tree2 tree3 |
+	git pack-objects missing-blob.git/objects/pack/side1-whatever-is-missing &&
+	test_must_fail git --git-dir=missing-blob.git >actual 2>err \
+		merge-tree --merge-base=$(cat tree1) $(cat tree2) $(cat tree3) &&
+	test_grep "unable to read blob object $(cat blob2)" err &&
+	test_must_be_empty actual
+'
+
+test_expect_success 'error out on missing commits as well' '
+	git init --bare missing-commit.git &&
+	git rev-list --objects side1 side3 >list-including-initial &&
+	grep -v ^$(git rev-parse side1^) <list-including-initial >list &&
+	git pack-objects missing-commit.git/objects/pack/missing-initial <list &&
+	side1=$(git rev-parse side1) &&
+	side3=$(git rev-parse side3) &&
+	test_must_fail git --git-dir=missing-commit.git \
+		merge-tree --allow-unrelated-histories $side1 $side3 >actual &&
+	test_must_be_empty actual
+'
+
 test_done

diff --git a/t/t5555-http-smart-common.sh b/t/t5555-http-smart-common.sh
index b1cfe8b..3dcb334 100755
--- a/t/t5555-http-smart-common.sh
+++ b/t/t5555-http-smart-common.sh

@@ -131,7 +131,6 @@
 	fetch=shallow wait-for-done
 	server-option
 	object-format=$(test_oid algo)
-	object-info
 	0000
 	EOF
 

diff --git a/t/t5701-git-serve.sh b/t/t5701-git-serve.sh
index 3591bc2..c48830d 100755
--- a/t/t5701-git-serve.sh
+++ b/t/t5701-git-serve.sh

@@ -20,7 +20,6 @@
 	fetch=shallow wait-for-done
 	server-option
 	object-format=$(test_oid algo)
-	object-info
 	EOF
 	cat >expect.trailer <<-EOF &&
 	0000
@@ -323,6 +322,8 @@
 # Test the basics of object-info
 #
 test_expect_success 'basics of object-info' '
+	test_config transfer.advertiseObjectInfo true &&
+
 	test-tool pkt-line pack >in <<-EOF &&
 	command=object-info
 	object-format=$(test_oid algo)
@@ -380,4 +381,25 @@
 	test_must_be_empty out
 '
 
+test_expect_success 'object-info missing from capabilities when disabled' '
+	test_config transfer.advertiseObjectInfo false &&
+
+	GIT_TEST_SIDEBAND_ALL=0 test-tool serve-v2 \
+		--advertise-capabilities >out &&
+	test-tool pkt-line unpack <out >actual &&
+
+	! grep object.info actual
+'
+
+test_expect_success 'object-info commands rejected when disabled' '
+	test_config transfer.advertiseObjectInfo false &&
+
+	test-tool pkt-line pack >in <<-EOF &&
+	command=object-info
+	EOF
+
+	test_must_fail test-tool serve-v2 --stateless-rpc <in 2>err &&
+	grep invalid.command err
+'
+
 test_done

diff --git a/t/t5702-protocol-v2.sh b/t/t5702-protocol-v2.sh
index 6ef4971..1ef540f 100755
--- a/t/t5702-protocol-v2.sh
+++ b/t/t5702-protocol-v2.sh

@@ -778,6 +778,25 @@
 	! grep ^GIT_PROTOCOL env.trace
 '
 
+test_expect_success 'reject client packfile-uris if not advertised' '
+	{
+		packetize command=fetch &&
+		packetize object-format=$(test_oid algo) &&
+		printf 0001 &&
+		packetize packfile-uris https &&
+		packetize done &&
+		printf 0000
+	} >input &&
+	test_must_fail env GIT_PROTOCOL=version=2 \
+		git upload-pack client <input &&
+	test_must_fail env GIT_PROTOCOL=version=2 \
+		git -c uploadpack.blobpackfileuri \
+		upload-pack client <input &&
+	GIT_PROTOCOL=version=2 \
+		git -c uploadpack.blobpackfileuri=anything \
+		upload-pack client <input
+'
+
 # Test protocol v2 with 'http://' transport
 #
 . "$TEST_DIRECTORY"/lib-httpd.sh

diff --git a/t/t5801/git-remote-testgit b/t/t5801/git-remote-testgit
index 1544d6d..bcfb358 100755
--- a/t/t5801/git-remote-testgit
+++ b/t/t5801/git-remote-testgit

@@ -12,6 +12,11 @@
 
 dir="$GIT_DIR/testgit/$alias"
 
+if ! git rev-parse --is-inside-git-dir
+then
+	exit 1
+fi
+
 h_refspec="refs/heads/*:refs/testgit/$alias/heads/*"
 t_refspec="refs/tags/*:refs/testgit/$alias/tags/*"
 

diff --git a/t/t6022-rev-list-missing.sh b/t/t6022-rev-list-missing.sh
index 2116727..127180e 100755
--- a/t/t6022-rev-list-missing.sh
+++ b/t/t6022-rev-list-missing.sh

@@ -10,7 +10,10 @@
 test_expect_success 'create repository and alternate directory' '
 	test_commit 1 &&
 	test_commit 2 &&
-	test_commit 3
+	test_commit 3 &&
+	git tag -m "tag message" annot_tag HEAD~1 &&
+	git tag regul_tag HEAD~1 &&
+	git branch a_branch HEAD~1
 '
 
 # We manually corrupt the repository, which means that the commit-graph may
@@ -46,9 +49,10 @@
 			git rev-list --objects --no-object-names \
 				HEAD ^$obj >expect.raw &&
 
-			# Blobs are shared by all commits, so evethough a commit/tree
+			# Blobs are shared by all commits, so even though a commit/tree
 			# might be skipped, its blob must be accounted for.
-			if [ $obj != "HEAD:1.t" ]; then
+			if test $obj != "HEAD:1.t"
+			then
 				echo $(git rev-parse HEAD:1.t) >>expect.raw &&
 				echo $(git rev-parse HEAD:2.t) >>expect.raw
 			fi &&
@@ -77,4 +81,69 @@
 	done
 done
 
+for missing_tip in "annot_tag" "regul_tag" "a_branch" "HEAD~1" "HEAD~1^{tree}" "HEAD:1.t"
+do
+	# We want to check that things work when both
+	#   - all the tips passed are missing (case existing_tip = ""), and
+	#   - there is one missing tip and one existing tip (case existing_tip = "HEAD")
+	for existing_tip in "" "HEAD"
+	do
+		for action in "allow-any" "print"
+		do
+			test_expect_success "--missing=$action with tip '$missing_tip' missing and tip '$existing_tip'" '
+				# Before the object is made missing, we use rev-list to
+				# get the expected oids.
+				if test "$existing_tip" = "HEAD"
+				then
+					git rev-list --objects --no-object-names \
+						HEAD ^$missing_tip >expect.raw
+				else
+					>expect.raw
+				fi &&
+
+				# Blobs are shared by all commits, so even though a commit/tree
+				# might be skipped, its blob must be accounted for.
+				if test "$existing_tip" = "HEAD" && test $missing_tip != "HEAD:1.t"
+				then
+					echo $(git rev-parse HEAD:1.t) >>expect.raw &&
+					echo $(git rev-parse HEAD:2.t) >>expect.raw
+				fi &&
+
+				missing_oid="$(git rev-parse $missing_tip)" &&
+
+				if test "$missing_tip" = "annot_tag"
+				then
+					oid="$(git rev-parse $missing_tip^{commit})" &&
+					echo "$missing_oid" >>expect.raw
+				else
+					oid="$missing_oid"
+				fi &&
+
+				path=".git/objects/$(test_oid_to_path $oid)" &&
+
+				mv "$path" "$path.hidden" &&
+				test_when_finished "mv $path.hidden $path" &&
+
+				git rev-list --missing=$action --objects --no-object-names \
+				     $missing_oid $existing_tip >actual.raw &&
+
+				# When the action is to print, we should also add the missing
+				# oid to the expect list.
+				case $action in
+				allow-any)
+					;;
+				print)
+					grep ?$oid actual.raw &&
+					echo ?$oid >>expect.raw
+					;;
+				esac &&
+
+				sort actual.raw >actual &&
+				sort expect.raw >expect &&
+				test_cmp expect actual
+			'
+		done
+	done
+done
+
 test_done

diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index 561080b..cdc0270 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh

@@ -878,7 +878,7 @@
 
 echo "" > expected.ok
 cat > expected.missing-tree.default <<EOF
-fatal: unable to read tree $deleted
+fatal: unable to read tree ($deleted)
 EOF
 
 test_expect_success 'bisect fails if tree is broken on start commit' '

diff --git a/t/t6302-for-each-ref-filter.sh b/t/t6302-for-each-ref-filter.sh
index 82f3d1e..948f1bb 100755
--- a/t/t6302-for-each-ref-filter.sh
+++ b/t/t6302-for-each-ref-filter.sh

@@ -31,6 +31,37 @@
 	git update-ref refs/odd/spot main
 '
 
+test_expect_success '--include-root-refs pattern prints pseudorefs' '
+	cat >expect <<-\EOF &&
+	HEAD
+	ORIG_HEAD
+	refs/heads/main
+	refs/heads/side
+	refs/odd/spot
+	refs/tags/annotated-tag
+	refs/tags/doubly-annotated-tag
+	refs/tags/doubly-signed-tag
+	refs/tags/four
+	refs/tags/one
+	refs/tags/signed-tag
+	refs/tags/three
+	refs/tags/two
+	EOF
+	git update-ref ORIG_HEAD main &&
+	git for-each-ref --format="%(refname)" --include-root-refs >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success '--include-root-refs with other patterns' '
+	cat >expect <<-\EOF &&
+	HEAD
+	ORIG_HEAD
+	EOF
+	git update-ref ORIG_HEAD main &&
+	git for-each-ref --format="%(refname)" --include-root-refs "*HEAD" >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'filtering with --points-at' '
 	cat >expect <<-\EOF &&
 	refs/heads/main

diff --git a/t/t6437-submodule-merge.sh b/t/t6437-submodule-merge.sh
index 7065052..7a3f1cb 100755
--- a/t/t6437-submodule-merge.sh
+++ b/t/t6437-submodule-merge.sh

@@ -113,7 +113,7 @@
 	 git checkout -b test-nonforward-a b &&
 	  if test "$GIT_TEST_MERGE_ALGORITHM" = ort
 	  then
-		test_must_fail git merge c >actual &&
+		test_must_fail git merge c 2>actual &&
 		sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
 		grep "$sub_expect" actual
 	  else
@@ -154,9 +154,9 @@
 	  git rev-parse --short sub-d > ../expect) &&
 	  if test "$GIT_TEST_MERGE_ALGORITHM" = ort
 	  then
-		test_must_fail git merge c >actual &&
+		test_must_fail git merge c >actual 2>sub-actual &&
 		sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
-		grep "$sub_expect" actual
+		grep "$sub_expect" sub-actual
 	  else
 		test_must_fail git merge c 2> actual
 	  fi &&
@@ -181,9 +181,9 @@
 	 ) &&
 	 if test "$GIT_TEST_MERGE_ALGORITHM" = ort
 	 then
-		test_must_fail git merge c >actual &&
+		test_must_fail git merge c >actual 2>sub-actual &&
 		sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
-		grep "$sub_expect" actual
+		grep "$sub_expect" sub-actual
 	 else
 		test_must_fail git merge c 2> actual
 	 fi &&
@@ -227,7 +227,7 @@
 	git commit -a -m "f" &&
 
 	git checkout -b test-backward e &&
-	test_must_fail git merge f >actual &&
+	test_must_fail git merge f 2>actual &&
 	if test "$GIT_TEST_MERGE_ALGORITHM" = ort
     then
 		sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-d)" &&
@@ -535,7 +535,7 @@
 	git checkout -b b init &&
 	git add sub &&
 	git commit -m "b" &&
-	test_must_fail git merge a >actual &&
+	test_must_fail git merge a 2>actual &&
 	if test "$GIT_TEST_MERGE_ALGORITHM" = ort
     then
 		sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short HEAD^1)" &&

diff --git a/t/t7402-submodule-rebase.sh b/t/t7402-submodule-rebase.sh
index 2b3c363..aa2fdc3 100755
--- a/t/t7402-submodule-rebase.sh
+++ b/t/t7402-submodule-rebase.sh

@@ -116,7 +116,7 @@
 	test_tick &&
 	git commit -m fourth &&
 
-	test_must_fail git rebase --onto HEAD^^ HEAD^ HEAD^0 >actual_output &&
+	test_must_fail git rebase --onto HEAD^^ HEAD^ HEAD^0 2>actual_output &&
 	git ls-files -s submodule >actual &&
 	(
 		cd submodule &&

diff --git a/t/t7502-commit-porcelain.sh b/t/t7502-commit-porcelain.sh
index a87c211..b37e201 100755
--- a/t/t7502-commit-porcelain.sh
+++ b/t/t7502-commit-porcelain.sh

@@ -736,6 +736,11 @@
 	  .git/COMMIT_EDITMSG
 '
 
+test_expect_success 'message does not have multiple scissors lines' '
+	git commit --cleanup=scissors -v --allow-empty -e -m foo &&
+	test $(grep -c -e "--- >8 ---" .git/COMMIT_EDITMSG) -eq 1
+'
+
 test_expect_success AUTOIDENT 'message shows committer when it is automatic' '
 
 	echo >>negative &&

diff --git a/t/unit-tests/t-ctype.c b/t/unit-tests/t-ctype.c
index f315489..d6ac1fe 100644
--- a/t/unit-tests/t-ctype.c
+++ b/t/unit-tests/t-ctype.c

@@ -1,30 +1,19 @@
 #include "test-lib.h"
 
-static int is_in(const char *s, int ch)
-{
-	/*
-	 * We can't find NUL using strchr. Accept it as the first
-	 * character in the spec -- there are no empty classes.
-	 */
-	if (ch == '\0')
-		return ch == *s;
-	if (*s == '\0')
-		s++;
-	return !!strchr(s, ch);
-}
-
-/* Macro to test a character type */
-#define TEST_CTYPE_FUNC(func, string) \
-static void test_ctype_##func(void) { \
-	for (int i = 0; i < 256; i++) { \
-		if (!check_int(func(i), ==, is_in(string, i))) \
-			test_msg("       i: 0x%02x", i); \
+#define TEST_CHAR_CLASS(class, string) do { \
+	size_t len = ARRAY_SIZE(string) - 1 + \
+		BUILD_ASSERT_OR_ZERO(ARRAY_SIZE(string) > 0) + \
+		BUILD_ASSERT_OR_ZERO(sizeof(string[0]) == sizeof(char)); \
+	int skip = test__run_begin(); \
+	if (!skip) { \
+		for (int i = 0; i < 256; i++) { \
+			if (!check_int(class(i), ==, !!memchr(string, i, len)))\
+				test_msg("      i: 0x%02x", i); \
+		} \
+		check(!class(EOF)); \
 	} \
-	if (!check(!func(EOF))) \
-			test_msg("      i: 0x%02x (EOF)", EOF); \
-}
-
-#define TEST_CHAR_CLASS(class) TEST(test_ctype_##class(), #class " works")
+	test__run_end(!skip, TEST_LOCATION(), #class " works"); \
+} while (0)
 
 #define DIGIT "0123456789"
 #define LOWER "abcdefghijklmnopqrstuvwxyz"
@@ -44,37 +33,21 @@ static void test_ctype_##func(void) { \
 	"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" \
 	"\x7f"
 
-TEST_CTYPE_FUNC(isdigit, DIGIT)
-TEST_CTYPE_FUNC(isspace, " \n\r\t")
-TEST_CTYPE_FUNC(isalpha, LOWER UPPER)
-TEST_CTYPE_FUNC(isalnum, LOWER UPPER DIGIT)
-TEST_CTYPE_FUNC(is_glob_special, "*?[\\")
-TEST_CTYPE_FUNC(is_regex_special, "$()*+.?[\\^{|")
-TEST_CTYPE_FUNC(is_pathspec_magic, "!\"#%&',-/:;<=>@_`~")
-TEST_CTYPE_FUNC(isascii, ASCII)
-TEST_CTYPE_FUNC(islower, LOWER)
-TEST_CTYPE_FUNC(isupper, UPPER)
-TEST_CTYPE_FUNC(iscntrl, CNTRL)
-TEST_CTYPE_FUNC(ispunct, PUNCT)
-TEST_CTYPE_FUNC(isxdigit, DIGIT "abcdefABCDEF")
-TEST_CTYPE_FUNC(isprint, LOWER UPPER DIGIT PUNCT " ")
-
 int cmd_main(int argc, const char **argv) {
-	/* Run all character type tests */
-	TEST_CHAR_CLASS(isspace);
-	TEST_CHAR_CLASS(isdigit);
-	TEST_CHAR_CLASS(isalpha);
-	TEST_CHAR_CLASS(isalnum);
-	TEST_CHAR_CLASS(is_glob_special);
-	TEST_CHAR_CLASS(is_regex_special);
-	TEST_CHAR_CLASS(is_pathspec_magic);
-	TEST_CHAR_CLASS(isascii);
-	TEST_CHAR_CLASS(islower);
-	TEST_CHAR_CLASS(isupper);
-	TEST_CHAR_CLASS(iscntrl);
-	TEST_CHAR_CLASS(ispunct);
-	TEST_CHAR_CLASS(isxdigit);
-	TEST_CHAR_CLASS(isprint);
+	TEST_CHAR_CLASS(isspace, " \n\r\t");
+	TEST_CHAR_CLASS(isdigit, DIGIT);
+	TEST_CHAR_CLASS(isalpha, LOWER UPPER);
+	TEST_CHAR_CLASS(isalnum, LOWER UPPER DIGIT);
+	TEST_CHAR_CLASS(is_glob_special, "*?[\\");
+	TEST_CHAR_CLASS(is_regex_special, "$()*+.?[\\^{|");
+	TEST_CHAR_CLASS(is_pathspec_magic, "!\"#%&',-/:;<=>@_`~");
+	TEST_CHAR_CLASS(isascii, ASCII);
+	TEST_CHAR_CLASS(islower, LOWER);
+	TEST_CHAR_CLASS(isupper, UPPER);
+	TEST_CHAR_CLASS(iscntrl, CNTRL);
+	TEST_CHAR_CLASS(ispunct, PUNCT);
+	TEST_CHAR_CLASS(isxdigit, DIGIT "abcdefABCDEF");
+	TEST_CHAR_CLASS(isprint, LOWER UPPER DIGIT PUNCT " ");
 
 	return test_done();
 }

diff --git a/tree-walk.c b/tree-walk.c
index b517792..690fa65 100644
--- a/tree-walk.c
+++ b/tree-walk.c

@@ -100,7 +100,7 @@ void *fill_tree_descriptor(struct repository *r,
 	if (oid) {
 		buf = read_object_with_reference(r, oid, OBJ_TREE, &size, NULL);
 		if (!buf)
-			die("unable to read tree %s", oid_to_hex(oid));
+			die(_("unable to read tree (%s)"), oid_to_hex(oid));
 	}
 	init_tree_desc(desc, buf, size);
 	return buf;

diff --git a/upload-pack.c b/upload-pack.c
index 2537aff..902144b 100644
--- a/upload-pack.c
+++ b/upload-pack.c

@@ -28,6 +28,7 @@
 #include "shallow.h"
 #include "write-or-die.h"
 #include "json-writer.h"
+#include "strmap.h"
 
 /* Remember to update object flag allocation in object.h */
 #define THEY_HAVE	(1u << 11)
@@ -61,12 +62,11 @@ struct upload_pack_data {
 	struct string_list symref;				/* v0 only */
 	struct object_array want_obj;
 	struct object_array have_obj;
-	struct oid_array haves;					/* v2 only */
-	struct string_list wanted_refs;				/* v2 only */
+	struct strmap wanted_refs;				/* v2 only */
 	struct strvec hidden_refs;
 
 	struct object_array shallows;
-	struct string_list deepen_not;
+	struct oidset deepen_not;
 	struct object_array extra_edge_obj;
 	int depth;
 	timestamp_t deepen_since;
@@ -113,6 +113,8 @@ struct upload_pack_data {
 	unsigned done : 1;					/* v2 only */
 	unsigned allow_ref_in_want : 1;				/* v2 only */
 	unsigned allow_sideband_all : 1;			/* v2 only */
+	unsigned seen_haves : 1;				/* v2 only */
+	unsigned allow_packfile_uris : 1;			/* v2 only */
 	unsigned advertise_sid : 1;
 	unsigned sent_capabilities : 1;
 };
@@ -120,13 +122,12 @@ struct upload_pack_data {
 static void upload_pack_data_init(struct upload_pack_data *data)
 {
 	struct string_list symref = STRING_LIST_INIT_DUP;
-	struct string_list wanted_refs = STRING_LIST_INIT_DUP;
+	struct strmap wanted_refs = STRMAP_INIT;
 	struct strvec hidden_refs = STRVEC_INIT;
 	struct object_array want_obj = OBJECT_ARRAY_INIT;
 	struct object_array have_obj = OBJECT_ARRAY_INIT;
-	struct oid_array haves = OID_ARRAY_INIT;
 	struct object_array shallows = OBJECT_ARRAY_INIT;
-	struct string_list deepen_not = STRING_LIST_INIT_DUP;
+	struct oidset deepen_not = OID_ARRAY_INIT;
 	struct string_list uri_protocols = STRING_LIST_INIT_DUP;
 	struct object_array extra_edge_obj = OBJECT_ARRAY_INIT;
 	struct string_list allowed_filters = STRING_LIST_INIT_DUP;
@@ -137,7 +138,6 @@ static void upload_pack_data_init(struct upload_pack_data *data)
 	data->hidden_refs = hidden_refs;
 	data->want_obj = want_obj;
 	data->have_obj = have_obj;
-	data->haves = haves;
 	data->shallows = shallows;
 	data->deepen_not = deepen_not;
 	data->uri_protocols = uri_protocols;
@@ -155,13 +155,12 @@ static void upload_pack_data_init(struct upload_pack_data *data)
 static void upload_pack_data_clear(struct upload_pack_data *data)
 {
 	string_list_clear(&data->symref, 1);
-	string_list_clear(&data->wanted_refs, 1);
+	strmap_clear(&data->wanted_refs, 1);
 	strvec_clear(&data->hidden_refs);
 	object_array_clear(&data->want_obj);
 	object_array_clear(&data->have_obj);
-	oid_array_clear(&data->haves);
 	object_array_clear(&data->shallows);
-	string_list_clear(&data->deepen_not, 0);
+	oidset_clear(&data->deepen_not);
 	object_array_clear(&data->extra_edge_obj);
 	list_objects_filter_release(&data->filter_options);
 	string_list_clear(&data->allowed_filters, 0);
@@ -463,7 +462,7 @@ static void create_pack_file(struct upload_pack_data *pack_data,
 
  fail:
 	free(output_state);
-	send_client_data(3, abort_msg, sizeof(abort_msg),
+	send_client_data(3, abort_msg, strlen(abort_msg),
 			 pack_data->use_sideband);
 	die("git upload-pack: %s", abort_msg);
 }
@@ -471,7 +470,9 @@ static void create_pack_file(struct upload_pack_data *pack_data,
 static int do_got_oid(struct upload_pack_data *data, const struct object_id *oid)
 {
 	int we_knew_they_have = 0;
-	struct object *o = parse_object(the_repository, oid);
+	struct object *o = parse_object_with_flags(the_repository, oid,
+						   PARSE_OBJECT_SKIP_HASH_CHECK |
+						   PARSE_OBJECT_DISCARD_TREE);
 
 	if (!o)
 		die("oops (%s)", oid_to_hex(oid));
@@ -528,8 +529,6 @@ static int get_common_commits(struct upload_pack_data *data,
 	int got_other = 0;
 	int sent_ready = 0;
 
-	save_commit_buffer = 0;
-
 	for (;;) {
 		const char *arg;
 
@@ -926,12 +925,13 @@ static int send_shallow_list(struct upload_pack_data *data)
 		strvec_push(&av, "rev-list");
 		if (data->deepen_since)
 			strvec_pushf(&av, "--max-age=%"PRItime, data->deepen_since);
-		if (data->deepen_not.nr) {
+		if (oidset_size(&data->deepen_not)) {
+			const struct object_id *oid;
+			struct oidset_iter iter;
 			strvec_push(&av, "--not");
-			for (i = 0; i < data->deepen_not.nr; i++) {
-				struct string_list_item *s = data->deepen_not.items + i;
-				strvec_push(&av, s->string);
-			}
+			oidset_iter_init(&data->deepen_not, &iter);
+			while ((oid = oidset_iter_next(&iter)))
+				strvec_push(&av, oid_to_hex(oid));
 			strvec_push(&av, "--not");
 		}
 		for (i = 0; i < data->want_obj.nr; i++) {
@@ -1007,7 +1007,7 @@ static int process_deepen_since(const char *line, timestamp_t *deepen_since, int
 	return 0;
 }
 
-static int process_deepen_not(const char *line, struct string_list *deepen_not, int *deepen_rev_list)
+static int process_deepen_not(const char *line, struct oidset *deepen_not, int *deepen_rev_list)
 {
 	const char *arg;
 	if (skip_prefix(line, "deepen-not ", &arg)) {
@@ -1015,7 +1015,7 @@ static int process_deepen_not(const char *line, struct string_list *deepen_not,
 		struct object_id oid;
 		if (expand_ref(the_repository, arg, strlen(arg), &oid, &ref) != 1)
 			die("git upload-pack: ambiguous deepen-not: %s", line);
-		string_list_append(deepen_not, ref);
+		oidset_insert(deepen_not, &oid);
 		free(ref);
 		*deepen_rev_list = 1;
 		return 1;
@@ -1151,7 +1151,9 @@ static void receive_needs(struct upload_pack_data *data,
 			free(client_sid);
 		}
 
-		o = parse_object(the_repository, &oid_buf);
+		o = parse_object_with_flags(the_repository, &oid_buf,
+					    PARSE_OBJECT_SKIP_HASH_CHECK |
+					    PARSE_OBJECT_DISCARD_TREE);
 		if (!o) {
 			packet_writer_error(&data->writer,
 					    "upload-pack: not our ref %s",
@@ -1362,6 +1364,9 @@ static int upload_pack_config(const char *var, const char *value,
 		data->allow_ref_in_want = git_config_bool(var, value);
 	} else if (!strcmp("uploadpack.allowsidebandall", var)) {
 		data->allow_sideband_all = git_config_bool(var, value);
+	} else if (!strcmp("uploadpack.blobpackfileuri", var)) {
+		if (value)
+			data->allow_packfile_uris = 1;
 	} else if (!strcmp("core.precomposeunicode", var)) {
 		precomposed_unicode = git_config_bool(var, value);
 	} else if (!strcmp("transfer.advertisesid", var)) {
@@ -1385,10 +1390,13 @@ static int upload_pack_protected_config(const char *var, const char *value,
 	return 0;
 }
 
-static void get_upload_pack_config(struct upload_pack_data *data)
+static void get_upload_pack_config(struct repository *r,
+				   struct upload_pack_data *data)
 {
-	git_config(upload_pack_config, data);
+	repo_config(r, upload_pack_config, data);
 	git_protected_config(upload_pack_protected_config, data);
+
+	data->allow_sideband_all |= git_env_bool("GIT_TEST_SIDEBAND_ALL", 0);
 }
 
 void upload_pack(const int advertise_refs, const int stateless_rpc,
@@ -1398,7 +1406,7 @@ void upload_pack(const int advertise_refs, const int stateless_rpc,
 	struct upload_pack_data data;
 
 	upload_pack_data_init(&data);
-	get_upload_pack_config(&data);
+	get_upload_pack_config(the_repository, &data);
 
 	data.stateless_rpc = stateless_rpc;
 	data.timeout = timeout;
@@ -1468,7 +1476,8 @@ static int parse_want(struct packet_writer *writer, const char *line,
 			    "expected to get oid, not '%s'", line);
 
 		o = parse_object_with_flags(the_repository, &oid,
-					    PARSE_OBJECT_SKIP_HASH_CHECK);
+					    PARSE_OBJECT_SKIP_HASH_CHECK |
+					    PARSE_OBJECT_DISCARD_TREE);
 
 		if (!o) {
 			packet_writer_error(writer,
@@ -1490,14 +1499,13 @@ static int parse_want(struct packet_writer *writer, const char *line,
 }
 
 static int parse_want_ref(struct packet_writer *writer, const char *line,
-			  struct string_list *wanted_refs,
+			  struct strmap *wanted_refs,
 			  struct strvec *hidden_refs,
 			  struct object_array *want_obj)
 {
 	const char *refname_nons;
 	if (skip_prefix(line, "want-ref ", &refname_nons)) {
 		struct object_id oid;
-		struct string_list_item *item;
 		struct object *o = NULL;
 		struct strbuf refname = STRBUF_INIT;
 
@@ -1509,8 +1517,11 @@ static int parse_want_ref(struct packet_writer *writer, const char *line,
 		}
 		strbuf_release(&refname);
 
-		item = string_list_append(wanted_refs, refname_nons);
-		item->util = oiddup(&oid);
+		if (strmap_put(wanted_refs, refname_nons, oiddup(&oid))) {
+			packet_writer_error(writer, "duplicate want-ref %s",
+					    refname_nons);
+			die("duplicate want-ref %s", refname_nons);
+		}
 
 		if (!starts_with(refname_nons, "refs/tags/")) {
 			struct commit *commit = lookup_commit_in_graph(the_repository, &oid);
@@ -1532,15 +1543,14 @@ static int parse_want_ref(struct packet_writer *writer, const char *line,
 	return 0;
 }
 
-static int parse_have(const char *line, struct oid_array *haves)
+static int parse_have(const char *line, struct upload_pack_data *data)
 {
 	const char *arg;
 	if (skip_prefix(line, "have ", &arg)) {
 		struct object_id oid;
 
-		if (get_oid_hex(arg, &oid))
-			die("git upload-pack: expected SHA1 object, got '%s'", arg);
-		oid_array_append(haves, &oid);
+		got_oid(data, arg, &oid);
+		data->seen_haves = 1;
 		return 1;
 	}
 
@@ -1552,13 +1562,13 @@ static void trace2_fetch_info(struct upload_pack_data *data)
 	struct json_writer jw = JSON_WRITER_INIT;
 
 	jw_object_begin(&jw, 0);
-	jw_object_intmax(&jw, "haves", data->haves.nr);
+	jw_object_intmax(&jw, "haves", data->have_obj.nr);
 	jw_object_intmax(&jw, "wants", data->want_obj.nr);
-	jw_object_intmax(&jw, "want-refs", data->wanted_refs.nr);
+	jw_object_intmax(&jw, "want-refs", strmap_get_size(&data->wanted_refs));
 	jw_object_intmax(&jw, "depth", data->depth);
 	jw_object_intmax(&jw, "shallows", data->shallows.nr);
 	jw_object_bool(&jw, "deepen-since", data->deepen_since);
-	jw_object_intmax(&jw, "deepen-not", data->deepen_not.nr);
+	jw_object_intmax(&jw, "deepen-not", oidset_size(&data->deepen_not));
 	jw_object_bool(&jw, "deepen-relative", data->deepen_relative);
 	if (data->filter_options.choice)
 		jw_object_string(&jw, "filter", list_object_filter_config_name(data->filter_options.choice));
@@ -1586,7 +1596,7 @@ static void process_args(struct packet_reader *request,
 				   &data->hidden_refs, &data->want_obj))
 			continue;
 		/* process have line */
-		if (parse_have(arg, &data->haves))
+		if (parse_have(arg, data))
 			continue;
 
 		/* process args like thin-pack */
@@ -1638,14 +1648,17 @@ static void process_args(struct packet_reader *request,
 			continue;
 		}
 
-		if ((git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
-		     data->allow_sideband_all) &&
+		if (data->allow_sideband_all &&
 		    !strcmp(arg, "sideband-all")) {
 			data->writer.use_sideband = 1;
 			continue;
 		}
 
-		if (skip_prefix(arg, "packfile-uris ", &p)) {
+		if (data->allow_packfile_uris &&
+		    skip_prefix(arg, "packfile-uris ", &p)) {
+			if (data->uri_protocols.nr)
+				send_err_and_die(data,
+						 "multiple packfile-uris lines forbidden");
 			string_list_split(&data->uri_protocols, p, ',', -1);
 			continue;
 		}
@@ -1664,27 +1677,7 @@ static void process_args(struct packet_reader *request,
 		trace2_fetch_info(data);
 }
 
-static int process_haves(struct upload_pack_data *data, struct oid_array *common)
-{
-	int i;
-
-	/* Process haves */
-	for (i = 0; i < data->haves.nr; i++) {
-		const struct object_id *oid = &data->haves.oid[i];
-
-		if (!repo_has_object_file_with_flags(the_repository, oid,
-						     OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT))
-			continue;
-
-		oid_array_append(common, oid);
-
-		do_got_oid(data, oid);
-	}
-
-	return 0;
-}
-
-static int send_acks(struct upload_pack_data *data, struct oid_array *acks)
+static int send_acks(struct upload_pack_data *data, struct object_array *acks)
 {
 	int i;
 
@@ -1696,7 +1689,7 @@ static int send_acks(struct upload_pack_data *data, struct oid_array *acks)
 
 	for (i = 0; i < acks->nr; i++) {
 		packet_writer_write(&data->writer, "ACK %s\n",
-				    oid_to_hex(&acks->oid[i]));
+				    oid_to_hex(&acks->objects[i].item->oid));
 	}
 
 	if (!data->wait_for_done && ok_to_give_up(data)) {
@@ -1710,13 +1703,11 @@ static int send_acks(struct upload_pack_data *data, struct oid_array *acks)
 
 static int process_haves_and_send_acks(struct upload_pack_data *data)
 {
-	struct oid_array common = OID_ARRAY_INIT;
 	int ret = 0;
 
-	process_haves(data, &common);
 	if (data->done) {
 		ret = 1;
-	} else if (send_acks(data, &common)) {
+	} else if (send_acks(data, &data->have_obj)) {
 		packet_writer_delim(&data->writer);
 		ret = 1;
 	} else {
@@ -1725,24 +1716,23 @@ static int process_haves_and_send_acks(struct upload_pack_data *data)
 		ret = 0;
 	}
 
-	oid_array_clear(&data->haves);
-	oid_array_clear(&common);
 	return ret;
 }
 
 static void send_wanted_ref_info(struct upload_pack_data *data)
 {
-	const struct string_list_item *item;
+	struct hashmap_iter iter;
+	const struct strmap_entry *e;
 
-	if (!data->wanted_refs.nr)
+	if (strmap_empty(&data->wanted_refs))
 		return;
 
 	packet_writer_write(&data->writer, "wanted-refs\n");
 
-	for_each_string_list_item(item, &data->wanted_refs) {
+	strmap_for_each_entry(&data->wanted_refs, &iter, e) {
 		packet_writer_write(&data->writer, "%s %s\n",
-				    oid_to_hex(item->util),
-				    item->string);
+				    oid_to_hex(e->value),
+				    e->key);
 	}
 
 	packet_writer_delim(&data->writer);
@@ -1771,7 +1761,7 @@ enum fetch_state {
 	FETCH_DONE,
 };
 
-int upload_pack_v2(struct repository *r UNUSED, struct packet_reader *request)
+int upload_pack_v2(struct repository *r, struct packet_reader *request)
 {
 	enum fetch_state state = FETCH_PROCESS_ARGS;
 	struct upload_pack_data data;
@@ -1780,7 +1770,7 @@ int upload_pack_v2(struct repository *r UNUSED, struct packet_reader *request)
 
 	upload_pack_data_init(&data);
 	data.use_sideband = LARGE_PACKET_MAX;
-	get_upload_pack_config(&data);
+	get_upload_pack_config(r, &data);
 
 	while (state != FETCH_DONE) {
 		switch (state) {
@@ -1796,7 +1786,7 @@ int upload_pack_v2(struct repository *r UNUSED, struct packet_reader *request)
 				 * they didn't want anything.
 				 */
 				state = FETCH_DONE;
-			} else if (data.haves.nr) {
+			} else if (data.seen_haves) {
 				/*
 				 * Request had 'have' lines, so lets ACK them.
 				 */
@@ -1839,41 +1829,28 @@ int upload_pack_v2(struct repository *r UNUSED, struct packet_reader *request)
 int upload_pack_advertise(struct repository *r,
 			  struct strbuf *value)
 {
-	if (value) {
-		int allow_filter_value;
-		int allow_ref_in_want;
-		int allow_sideband_all_value;
-		char *str = NULL;
+	struct upload_pack_data data;
 
+	upload_pack_data_init(&data);
+	get_upload_pack_config(r, &data);
+
+	if (value) {
 		strbuf_addstr(value, "shallow wait-for-done");
 
-		if (!repo_config_get_bool(r,
-					 "uploadpack.allowfilter",
-					 &allow_filter_value) &&
-		    allow_filter_value)
+		if (data.allow_filter)
 			strbuf_addstr(value, " filter");
 
-		if (!repo_config_get_bool(r,
-					 "uploadpack.allowrefinwant",
-					 &allow_ref_in_want) &&
-		    allow_ref_in_want)
+		if (data.allow_ref_in_want)
 			strbuf_addstr(value, " ref-in-want");
 
-		if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
-		    (!repo_config_get_bool(r,
-					   "uploadpack.allowsidebandall",
-					   &allow_sideband_all_value) &&
-		     allow_sideband_all_value))
+		if (data.allow_sideband_all)
 			strbuf_addstr(value, " sideband-all");
 
-		if (!repo_config_get_string(r,
-					    "uploadpack.blobpackfileuri",
-					    &str) &&
-		    str) {
+		if (data.allow_packfile_uris)
 			strbuf_addstr(value, " packfile-uris");
-			free(str);
-		}
 	}
 
+	upload_pack_data_clear(&data);
+
 	return 1;
 }

diff --git a/userdiff.c b/userdiff.c
index 2b1dab2..92ef649 100644
--- a/userdiff.c
+++ b/userdiff.c

@@ -3,6 +3,7 @@
 #include "userdiff.h"
 #include "attr.h"
 #include "strbuf.h"
+#include "environment.h"
 
 static struct userdiff_driver *drivers;
 static int ndrivers;
@@ -459,7 +460,8 @@ struct userdiff_driver *userdiff_get_textconv(struct repository *r,
 	if (!driver->textconv)
 		return NULL;
 
-	if (driver->textconv_want_cache && !driver->textconv_cache) {
+	if (driver->textconv_want_cache && !driver->textconv_cache &&
+	    have_git_dir()) {
 		struct notes_cache *c = xmalloc(sizeof(*c));
 		struct strbuf name = STRBUF_INIT;
 

diff --git a/wt-status.c b/wt-status.c
index b5a2908..7108a92 100644
--- a/wt-status.c
+++ b/wt-status.c

@@ -1107,12 +1107,15 @@ void wt_status_append_cut_line(struct strbuf *buf)
 	strbuf_add_commented_lines(buf, explanation, strlen(explanation), comment_line_char);
 }
 
-void wt_status_add_cut_line(FILE *fp)
+void wt_status_add_cut_line(struct wt_status *s)
 {
 	struct strbuf buf = STRBUF_INIT;
 
+	if (s->added_cut_line)
+		return;
+	s->added_cut_line = 1;
 	wt_status_append_cut_line(&buf);
-	fputs(buf.buf, fp);
+	fputs(buf.buf, s->fp);
 	strbuf_release(&buf);
 }
 
@@ -1143,11 +1146,12 @@ static void wt_longstatus_print_verbose(struct wt_status *s)
 	 * file (and even the "auto" setting won't work, since it
 	 * will have checked isatty on stdout). But we then do want
 	 * to insert the scissor line here to reliably remove the
-	 * diff before committing.
+	 * diff before committing, if we didn't already include one
+	 * before.
 	 */
 	if (s->fp != stdout) {
 		rev.diffopt.use_color = 0;
-		wt_status_add_cut_line(s->fp);
+		wt_status_add_cut_line(s);
 	}
 	if (s->verbose > 1 && s->committable) {
 		/* print_updated() printed a header, so do we */

diff --git a/wt-status.h b/wt-status.h
index 819dcad..5e99ba4 100644
--- a/wt-status.h
+++ b/wt-status.h

@@ -130,6 +130,7 @@ struct wt_status {
 	int rename_score;
 	int rename_limit;
 	enum wt_status_format status_format;
+	unsigned char added_cut_line; /* boolean */
 	struct wt_status_state state;
 	struct object_id oid_commit; /* when not Initial */
 
@@ -147,7 +148,7 @@ struct wt_status {
 
 size_t wt_status_locate_end(const char *s, size_t len);
 void wt_status_append_cut_line(struct strbuf *buf);
-void wt_status_add_cut_line(FILE *fp);
+void wt_status_add_cut_line(struct wt_status *s);
 void wt_status_prepare(struct repository *r, struct wt_status *s);
 void wt_status_print(struct wt_status *s);
 void wt_status_collect(struct wt_status *s);