diff --git a/Documentation/RelNotes/2.54.0.adoc b/Documentation/RelNotes/2.54.0.adoc
index 005a98e0ff1a39..d7c67cbb078aeb 100644
--- a/Documentation/RelNotes/2.54.0.adoc
+++ b/Documentation/RelNotes/2.54.0.adoc
@@ -85,6 +85,9 @@ UI, Workflows & Features
    and various other branches listed on status.compareBranches
    configuration.
 
+ * "git repo structure" command learns to report maximum values on
+   various aspects of objects it inspects.
+
 
 Performance, Internal Implementation, Development Support etc.
 --------------------------------------------------------------
@@ -187,6 +190,9 @@ Performance, Internal Implementation, Development Support etc.
  * The object source API is getting restructured to allow plugging new
    backends.
 
+ * Reduce dependence on the global the_hash_algo and the_repository
+   variables of wt-status code path.
+
 
 Fixes since v2.53
 -----------------
@@ -301,6 +307,22 @@ Fixes since v2.53
  * "git for-each-repo" started from a secondary worktree did not work
    as expected, which has been corrected.
    (merge e87493b9b4 ds/for-each-repo-w-worktree later to maint).
+
+ * The construct 'test "$(command)" = expectation' loses the exit
+   status from the command, which has been fixed by breaking up the
+   statement into pieces.
+   (merge d3edca979a fp/t3310-unhide-git-failures later to maint).
+
+ * While discovering a ".git" directory, the code treats any stat()
+   failure as a sign that a filesystem entity .git does not exist
+   there, and ignores ".git" that is not a "gitdir" file or a
+   directory.  The code has been tightened to notice and report
+   filesystem corruption better.
+   (merge 1dd27bfbfd ty/setup-error-tightening later to maint).
+
+ * Plug a few leaks where mmap'ed memory regions are not unmapped.
+   (merge a8a69bbb64 jk/unleak-mmap later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge d79fff4a11 jk/remote-tracking-ref-leakfix later to maint).
    (merge 7a747f972d dd/t5403-modernise later to maint).
@@ -338,3 +360,5 @@ Fixes since v2.53
    (merge a56fa1ca05 lp/doc-gitprotocol-pack-fixes later to maint).
    (merge 0d6bb8b541 ss/t3700-modernize later to maint).
    (merge 63c00a677b ss/t9123-setup-inside-test-expect-success later to maint).
+   (merge beca0ca4be os/doc-git-custom-commands later to maint).
+   (merge 4c223571be ty/patch-ids-document-lazy-eval later to maint).
diff --git a/Documentation/git-repo.adoc b/Documentation/git-repo.adoc
index 5e2968b707eacd..42262c198347e5 100644
--- a/Documentation/git-repo.adoc
+++ b/Documentation/git-repo.adoc
@@ -64,6 +64,7 @@ supported:
 * Reachable object counts categorized by type
 * Total inflated size of reachable objects by type
 * Total disk size of reachable objects by type
+* Largest reachable objects in the repository by type
 +
 The output format can be chosen through the flag `--format`. Three formats are
 supported:
diff --git a/Documentation/git.adoc b/Documentation/git.adoc
index 2b3d1d2d0c599d..8a5cdd3b3d22c5 100644
--- a/Documentation/git.adoc
+++ b/Documentation/git.adoc
@@ -235,7 +235,10 @@ GIT COMMANDS
 ------------
 
 We divide Git into high level ("porcelain") commands and low level
-("plumbing") commands.
+("plumbing") commands.  For defining command aliases, see
+linkgit:git-config[1] and look for descriptions of `alias.*`.
+For installing custom "git" subcommands, see the description for
+the 'PATH' environment variable in this manual.
 
 High-level commands (porcelain)
 -------------------------------
diff --git a/Makefile b/Makefile
index 58fb895f4e2f23..c619b5405b5300 100644
--- a/Makefile
+++ b/Makefile
@@ -1605,6 +1605,7 @@ BASIC_CFLAGS += -DSHA1DC_FORCE_ALIGNED_ACCESS
 endif
 ifneq ($(filter leak,$(SANITIZERS)),)
 BASIC_CFLAGS += -O0
+NO_MMAP = CatchMapLeaks
 SANITIZE_LEAK = YesCompiledWithIt
 endif
 ifneq ($(filter address,$(SANITIZERS)),)
diff --git a/builtin/history.c b/builtin/history.c
index 1cf6c668cfd814..88822a184fa5bc 100644
--- a/builtin/history.c
+++ b/builtin/history.c
@@ -425,7 +425,7 @@ static int cmd_history_reword(int argc,
 	};
 	struct strbuf reflog_msg = STRBUF_INIT;
 	struct commit *original, *rewritten;
-	struct rev_info revs;
+	struct rev_info revs = { 0 };
 	int ret;
 
 	argc = parse_options(argc, argv, prefix, options, usage, 0);
diff --git a/builtin/repo.c b/builtin/repo.c
index fae1141cff2e31..55f9b9095c1f92 100644
--- a/builtin/repo.c
+++ b/builtin/repo.c
@@ -1,7 +1,9 @@
 #define USE_THE_REPOSITORY_VARIABLE
 
 #include "builtin.h"
+#include "commit.h"
 #include "environment.h"
+#include "hash.h"
 #include "hex.h"
 #include "odb.h"
 #include "parse-options.h"
@@ -14,6 +16,8 @@
 #include "strbuf.h"
 #include "string-list.h"
 #include "shallow.h"
+#include "tree.h"
+#include "tree-walk.h"
 #include "utf8.h"
 
 static const char *const repo_usage[] = {
@@ -230,6 +234,21 @@ static int cmd_repo_info(int argc, const char **argv, const char *prefix,
 		return print_fields(argc, argv, repo, format);
 }
 
+struct object_data {
+	struct object_id oid;
+	size_t value;
+};
+
+struct largest_objects {
+	struct object_data tag_size;
+	struct object_data commit_size;
+	struct object_data tree_size;
+	struct object_data blob_size;
+
+	struct object_data parent_count;
+	struct object_data tree_entries;
+};
+
 struct ref_stats {
 	size_t branches;
 	size_t remotes;
@@ -248,6 +267,7 @@ struct object_stats {
 	struct object_values type_counts;
 	struct object_values inflated_sizes;
 	struct object_values disk_sizes;
+	struct largest_objects largest;
 };
 
 struct repo_structure {
@@ -257,6 +277,7 @@ struct repo_structure {
 
 struct stats_table {
 	struct string_list rows;
+	struct string_list annotations;
 
 	int name_col_width;
 	int value_col_width;
@@ -269,6 +290,8 @@ struct stats_table {
 struct stats_table_entry {
 	char *value;
 	const char *unit;
+	size_t index;
+	struct object_id *oid;
 };
 
 static void stats_table_vaddf(struct stats_table *table,
@@ -291,6 +314,12 @@ static void stats_table_vaddf(struct stats_table *table,
 		table->name_col_width = name_width;
 	if (!entry)
 		return;
+	if (entry->oid) {
+		entry->index = table->annotations.nr + 1;
+		strbuf_addf(&buf, "[%" PRIuMAX "] %s", (uintmax_t)entry->index,
+			    oid_to_hex(entry->oid));
+		string_list_append_nodup(&table->annotations, strbuf_detach(&buf, NULL));
+	}
 	if (entry->value) {
 		int value_width = utf8_strwidth(entry->value);
 		if (value_width > table->value_col_width)
@@ -301,6 +330,8 @@ static void stats_table_vaddf(struct stats_table *table,
 		if (unit_width > table->unit_col_width)
 			table->unit_col_width = unit_width;
 	}
+
+	strbuf_release(&buf);
 }
 
 static void stats_table_addf(struct stats_table *table, const char *format, ...)
@@ -326,6 +357,27 @@ static void stats_table_count_addf(struct stats_table *table, size_t value,
 	va_end(ap);
 }
 
+static void stats_table_object_count_addf(struct stats_table *table,
+					  struct object_id *oid, size_t value,
+					  const char *format, ...)
+{
+	struct stats_table_entry *entry;
+	va_list ap;
+
+	CALLOC_ARRAY(entry, 1);
+	humanise_count(value, &entry->value, &entry->unit);
+
+	/*
+	 * A NULL OID should not have a table annotation.
+	 */
+	if (!is_null_oid(oid))
+		entry->oid = oid;
+
+	va_start(ap, format);
+	stats_table_vaddf(table, entry, format, ap);
+	va_end(ap);
+}
+
 static void stats_table_size_addf(struct stats_table *table, size_t value,
 				  const char *format, ...)
 {
@@ -340,6 +392,27 @@ static void stats_table_size_addf(struct stats_table *table, size_t value,
 	va_end(ap);
 }
 
+static void stats_table_object_size_addf(struct stats_table *table,
+					 struct object_id *oid, size_t value,
+					 const char *format, ...)
+{
+	struct stats_table_entry *entry;
+	va_list ap;
+
+	CALLOC_ARRAY(entry, 1);
+	humanise_bytes(value, &entry->value, &entry->unit, HUMANISE_COMPACT);
+
+	/*
+	 * A NULL OID should not have a table annotation.
+	 */
+	if (!is_null_oid(oid))
+		entry->oid = oid;
+
+	va_start(ap, format);
+	stats_table_vaddf(table, entry, format, ap);
+	va_end(ap);
+}
+
 static inline size_t get_total_reference_count(struct ref_stats *stats)
 {
 	return stats->branches + stats->remotes + stats->tags + stats->others;
@@ -404,8 +477,41 @@ static void stats_table_setup_structure(struct stats_table *table,
 			      "    * %s", _("Blobs"));
 	stats_table_size_addf(table, objects->disk_sizes.tags,
 			      "    * %s", _("Tags"));
+
+	stats_table_addf(table, "");
+	stats_table_addf(table, "* %s", _("Largest objects"));
+	stats_table_addf(table, "  * %s", _("Commits"));
+	stats_table_object_size_addf(table,
+				     &objects->largest.commit_size.oid,
+				     objects->largest.commit_size.value,
+				     "    * %s", _("Maximum size"));
+	stats_table_object_count_addf(table,
+				      &objects->largest.parent_count.oid,
+				      objects->largest.parent_count.value,
+				      "    * %s", _("Maximum parents"));
+	stats_table_addf(table, "  * %s", _("Trees"));
+	stats_table_object_size_addf(table,
+				     &objects->largest.tree_size.oid,
+				     objects->largest.tree_size.value,
+				     "    * %s", _("Maximum size"));
+	stats_table_object_count_addf(table,
+				      &objects->largest.tree_entries.oid,
+				      objects->largest.tree_entries.value,
+				      "    * %s", _("Maximum entries"));
+	stats_table_addf(table, "  * %s", _("Blobs"));
+	stats_table_object_size_addf(table,
+				     &objects->largest.blob_size.oid,
+				     objects->largest.blob_size.value,
+				     "    * %s", _("Maximum size"));
+	stats_table_addf(table, "  * %s", _("Tags"));
+	stats_table_object_size_addf(table,
+				     &objects->largest.tag_size.oid,
+				     objects->largest.tag_size.value,
+				     "    * %s", _("Maximum size"));
 }
 
+#define INDEX_WIDTH 4
+
 static void stats_table_print_structure(const struct stats_table *table)
 {
 	const char *name_col_title = _("Repository structure");
@@ -424,7 +530,8 @@ static void stats_table_print_structure(const struct stats_table *table)
 		value_col_width = title_value_width - unit_col_width;
 
 	strbuf_addstr(&buf, "| ");
-	strbuf_utf8_align(&buf, ALIGN_LEFT, name_col_width, name_col_title);
+	strbuf_utf8_align(&buf, ALIGN_LEFT, name_col_width + INDEX_WIDTH,
+			  name_col_title);
 	strbuf_addstr(&buf, " | ");
 	strbuf_utf8_align(&buf, ALIGN_LEFT,
 			  value_col_width + unit_col_width + 1, value_col_title);
@@ -432,7 +539,7 @@ static void stats_table_print_structure(const struct stats_table *table)
 	printf("%s\n", buf.buf);
 
 	printf("| ");
-	for (int i = 0; i < name_col_width; i++)
+	for (int i = 0; i < name_col_width + INDEX_WIDTH; i++)
 		putchar('-');
 	printf(" | ");
 	for (int i = 0; i < value_col_width + unit_col_width + 1; i++)
@@ -453,6 +560,13 @@ static void stats_table_print_structure(const struct stats_table *table)
 		strbuf_reset(&buf);
 		strbuf_addstr(&buf, "| ");
 		strbuf_utf8_align(&buf, ALIGN_LEFT, name_col_width, item->string);
+
+		if (entry && entry->oid)
+			strbuf_addf(&buf, " [%" PRIuMAX "]",
+				    (uintmax_t)entry->index);
+		else
+			strbuf_addchars(&buf, ' ', INDEX_WIDTH);
+
 		strbuf_addstr(&buf, " | ");
 		strbuf_utf8_align(&buf, ALIGN_RIGHT, value_col_width, value);
 		strbuf_addch(&buf, ' ');
@@ -461,6 +575,12 @@ static void stats_table_print_structure(const struct stats_table *table)
 		printf("%s\n", buf.buf);
 	}
 
+	if (table->annotations.nr) {
+		printf("\n");
+		for_each_string_list_item(item, &table->annotations)
+			printf("%s\n", item->string);
+	}
+
 	strbuf_release(&buf);
 }
 
@@ -476,46 +596,76 @@ static void stats_table_clear(struct stats_table *table)
 	}
 
 	string_list_clear(&table->rows, 1);
+	string_list_clear(&table->annotations, 1);
+}
+
+static inline void print_keyvalue(const char *key, char key_delim, size_t value,
+				  char value_delim)
+{
+	printf("%s%c%" PRIuMAX "%c", key, key_delim, (uintmax_t)value,
+	       value_delim);
+}
+
+static void print_object_data(const char *key, char key_delim,
+			      struct object_data *data, char value_delim)
+{
+	print_keyvalue(key, key_delim, data->value, value_delim);
+	printf("%s_oid%c%s%c", key, key_delim, oid_to_hex(&data->oid),
+	       value_delim);
 }
 
 static void structure_keyvalue_print(struct repo_structure *stats,
 				     char key_delim, char value_delim)
 {
-	printf("references.branches.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->refs.branches, value_delim);
-	printf("references.tags.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->refs.tags, value_delim);
-	printf("references.remotes.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->refs.remotes, value_delim);
-	printf("references.others.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->refs.others, value_delim);
-
-	printf("objects.commits.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.type_counts.commits, value_delim);
-	printf("objects.trees.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.type_counts.trees, value_delim);
-	printf("objects.blobs.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.type_counts.blobs, value_delim);
-	printf("objects.tags.count%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.type_counts.tags, value_delim);
-
-	printf("objects.commits.inflated_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.inflated_sizes.commits, value_delim);
-	printf("objects.trees.inflated_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.inflated_sizes.trees, value_delim);
-	printf("objects.blobs.inflated_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.inflated_sizes.blobs, value_delim);
-	printf("objects.tags.inflated_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.inflated_sizes.tags, value_delim);
-
-	printf("objects.commits.disk_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.disk_sizes.commits, value_delim);
-	printf("objects.trees.disk_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.disk_sizes.trees, value_delim);
-	printf("objects.blobs.disk_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.disk_sizes.blobs, value_delim);
-	printf("objects.tags.disk_size%c%" PRIuMAX "%c", key_delim,
-	       (uintmax_t)stats->objects.disk_sizes.tags, value_delim);
+	print_keyvalue("references.branches.count", key_delim,
+		       stats->refs.branches, value_delim);
+	print_keyvalue("references.tags.count", key_delim,
+		       stats->refs.tags, value_delim);
+	print_keyvalue("references.remotes.count", key_delim,
+		       stats->refs.remotes, value_delim);
+	print_keyvalue("references.others.count", key_delim,
+		       stats->refs.others, value_delim);
+
+	print_keyvalue("objects.commits.count", key_delim,
+		       stats->objects.type_counts.commits, value_delim);
+	print_keyvalue("objects.trees.count", key_delim,
+		       stats->objects.type_counts.trees, value_delim);
+	print_keyvalue("objects.blobs.count", key_delim,
+		       stats->objects.type_counts.blobs, value_delim);
+	print_keyvalue("objects.tags.count", key_delim,
+		       stats->objects.type_counts.tags, value_delim);
+
+	print_keyvalue("objects.commits.inflated_size", key_delim,
+		       stats->objects.inflated_sizes.commits, value_delim);
+	print_keyvalue("objects.trees.inflated_size", key_delim,
+		       stats->objects.inflated_sizes.trees, value_delim);
+	print_keyvalue("objects.blobs.inflated_size", key_delim,
+		       stats->objects.inflated_sizes.blobs, value_delim);
+	print_keyvalue("objects.tags.inflated_size", key_delim,
+		       stats->objects.inflated_sizes.tags, value_delim);
+
+	print_keyvalue("objects.commits.disk_size", key_delim,
+		       stats->objects.disk_sizes.commits, value_delim);
+	print_keyvalue("objects.trees.disk_size", key_delim,
+		       stats->objects.disk_sizes.trees, value_delim);
+	print_keyvalue("objects.blobs.disk_size", key_delim,
+		       stats->objects.disk_sizes.blobs, value_delim);
+	print_keyvalue("objects.tags.disk_size", key_delim,
+		       stats->objects.disk_sizes.tags, value_delim);
+
+	print_object_data("objects.commits.max_size", key_delim,
+			  &stats->objects.largest.commit_size, value_delim);
+	print_object_data("objects.trees.max_size", key_delim,
+			  &stats->objects.largest.tree_size, value_delim);
+	print_object_data("objects.blobs.max_size", key_delim,
+			  &stats->objects.largest.blob_size, value_delim);
+	print_object_data("objects.tags.max_size", key_delim,
+			  &stats->objects.largest.tag_size, value_delim);
+
+	print_object_data("objects.commits.max_parents", key_delim,
+			  &stats->objects.largest.parent_count, value_delim);
+	print_object_data("objects.trees.max_entries", key_delim,
+			  &stats->objects.largest.tree_entries, value_delim);
 
 	fflush(stdout);
 }
@@ -585,55 +735,97 @@ struct count_objects_data {
 	struct progress *progress;
 };
 
+static void check_largest(struct object_data *data, struct object_id *oid,
+			  size_t value)
+{
+	if (value > data->value || is_null_oid(&data->oid)) {
+		oidcpy(&data->oid, oid);
+		data->value = value;
+	}
+}
+
+static size_t count_tree_entries(struct object *obj)
+{
+	struct tree *t = object_as_type(obj, OBJ_TREE, 0);
+	struct name_entry entry;
+	struct tree_desc desc;
+	size_t count = 0;
+
+	init_tree_desc(&desc, &t->object.oid, t->buffer, t->size);
+	while (tree_entry(&desc, &entry))
+		count++;
+
+	return count;
+}
+
 static int count_objects(const char *path UNUSED, struct oid_array *oids,
 			 enum object_type type, void *cb_data)
 {
 	struct count_objects_data *data = cb_data;
 	struct object_stats *stats = data->stats;
-	size_t inflated_total = 0;
-	size_t disk_total = 0;
 	size_t object_count;
 
 	for (size_t i = 0; i < oids->nr; i++) {
 		struct object_info oi = OBJECT_INFO_INIT;
 		unsigned long inflated;
+		struct commit *commit;
+		struct object *obj;
+		void *content;
 		off_t disk;
+		int eaten;
 
 		oi.sizep = &inflated;
 		oi.disk_sizep = &disk;
+		oi.contentp = &content;
 
 		if (odb_read_object_info_extended(data->odb, &oids->oid[i], &oi,
 						  OBJECT_INFO_SKIP_FETCH_OBJECT |
 						  OBJECT_INFO_QUICK) < 0)
 			continue;
 
-		inflated_total += inflated;
-		disk_total += disk;
-	}
+		obj = parse_object_buffer(the_repository, &oids->oid[i], type,
+					  inflated, content, &eaten);
+
+		switch (type) {
+		case OBJ_TAG:
+			stats->type_counts.tags++;
+			stats->inflated_sizes.tags += inflated;
+			stats->disk_sizes.tags += disk;
+			check_largest(&stats->largest.tag_size, &oids->oid[i],
+				      inflated);
+			break;
+		case OBJ_COMMIT:
+			commit = object_as_type(obj, OBJ_COMMIT, 0);
+			stats->type_counts.commits++;
+			stats->inflated_sizes.commits += inflated;
+			stats->disk_sizes.commits += disk;
+			check_largest(&stats->largest.commit_size, &oids->oid[i],
+				      inflated);
+			check_largest(&stats->largest.parent_count, &oids->oid[i],
+				      commit_list_count(commit->parents));
+			break;
+		case OBJ_TREE:
+			stats->type_counts.trees++;
+			stats->inflated_sizes.trees += inflated;
+			stats->disk_sizes.trees += disk;
+			check_largest(&stats->largest.tree_size, &oids->oid[i],
+				      inflated);
+			check_largest(&stats->largest.tree_entries, &oids->oid[i],
+				      count_tree_entries(obj));
+			break;
+		case OBJ_BLOB:
+			stats->type_counts.blobs++;
+			stats->inflated_sizes.blobs += inflated;
+			stats->disk_sizes.blobs += disk;
+			check_largest(&stats->largest.blob_size, &oids->oid[i],
+				      inflated);
+			break;
+		default:
+			BUG("invalid object type");
+		}
 
-	switch (type) {
-	case OBJ_TAG:
-		stats->type_counts.tags += oids->nr;
-		stats->inflated_sizes.tags += inflated_total;
-		stats->disk_sizes.tags += disk_total;
-		break;
-	case OBJ_COMMIT:
-		stats->type_counts.commits += oids->nr;
-		stats->inflated_sizes.commits += inflated_total;
-		stats->disk_sizes.commits += disk_total;
-		break;
-	case OBJ_TREE:
-		stats->type_counts.trees += oids->nr;
-		stats->inflated_sizes.trees += inflated_total;
-		stats->disk_sizes.trees += disk_total;
-		break;
-	case OBJ_BLOB:
-		stats->type_counts.blobs += oids->nr;
-		stats->inflated_sizes.blobs += inflated_total;
-		stats->disk_sizes.blobs += disk_total;
-		break;
-	default:
-		BUG("invalid object type");
+		if (!eaten)
+			free(content);
 	}
 
 	object_count = get_total_object_values(&stats->type_counts);
@@ -669,6 +861,7 @@ static int cmd_repo_structure(int argc, const char **argv, const char *prefix,
 {
 	struct stats_table table = {
 		.rows = STRING_LIST_INIT_DUP,
+		.annotations = STRING_LIST_INIT_DUP,
 	};
 	enum output_format format = FORMAT_TABLE;
 	struct repo_structure stats = { 0 };
diff --git a/connected.c b/connected.c
index 79403108dd8f57..6718503649da8a 100644
--- a/connected.c
+++ b/connected.c
@@ -45,20 +45,6 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 		return err;
 	}
 
-	if (transport && transport->smart_options &&
-	    transport->smart_options->self_contained_and_connected &&
-	    transport->pack_lockfiles.nr == 1 &&
-	    strip_suffix(transport->pack_lockfiles.items[0].string,
-			 ".keep", &base_len)) {
-		struct strbuf idx_file = STRBUF_INIT;
-		strbuf_add(&idx_file, transport->pack_lockfiles.items[0].string,
-			   base_len);
-		strbuf_addstr(&idx_file, ".idx");
-		new_pack = add_packed_git(the_repository, idx_file.buf,
-					  idx_file.len, 1);
-		strbuf_release(&idx_file);
-	}
-
 	if (repo_has_promisor_remote(the_repository)) {
 		/*
 		 * For partial clones, we don't want to have to do a regular
@@ -90,7 +76,6 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 promisor_pack_found:
 			;
 		} while ((oid = fn(cb_data)) != NULL);
-		free(new_pack);
 		return 0;
 	}
 
@@ -127,15 +112,27 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 	else
 		rev_list.no_stderr = opt->quiet;
 
-	if (start_command(&rev_list)) {
-		free(new_pack);
+	if (start_command(&rev_list))
 		return error(_("Could not run 'git rev-list'"));
-	}
 
 	sigchain_push(SIGPIPE, SIG_IGN);
 
 	rev_list_in = xfdopen(rev_list.in, "w");
 
+	if (transport && transport->smart_options &&
+	    transport->smart_options->self_contained_and_connected &&
+	    transport->pack_lockfiles.nr == 1 &&
+	    strip_suffix(transport->pack_lockfiles.items[0].string,
+			 ".keep", &base_len)) {
+		struct strbuf idx_file = STRBUF_INIT;
+		strbuf_add(&idx_file, transport->pack_lockfiles.items[0].string,
+			   base_len);
+		strbuf_addstr(&idx_file, ".idx");
+		new_pack = add_packed_git(the_repository, idx_file.buf,
+					  idx_file.len, 1);
+		strbuf_release(&idx_file);
+	}
+
 	do {
 		/*
 		 * If index-pack already checked that:
@@ -162,6 +159,9 @@ int check_connected(oid_iterate_fn fn, void *cb_data,
 		err = error_errno(_("failed to close rev-list's stdin"));
 
 	sigchain_pop(SIGPIPE);
-	free(new_pack);
+	if (new_pack) {
+		close_pack(new_pack);
+		free(new_pack);
+	}
 	return finish_command(&rev_list) || err;
 }
diff --git a/meson.build b/meson.build
index 1036eafc3c0d0c..9e9ba9b82b80ea 100644
--- a/meson.build
+++ b/meson.build
@@ -1438,7 +1438,7 @@ else
     'getpagesize' : [],
   }
 
-  if get_option('b_sanitize').contains('address')
+  if get_option('b_sanitize').contains('address') or get_option('b_sanitize').contains('leak')
     libgit_c_args += '-DNO_MMAP'
     libgit_sources += 'compat/mmap.c'
   else
diff --git a/object-file.c b/object-file.c
index a3ff7f586c91f3..c62e5496e0795d 100644
--- a/object-file.c
+++ b/object-file.c
@@ -2211,7 +2211,7 @@ int odb_source_loose_read_object_stream(struct odb_read_stream **out,
 	return 0;
 error:
 	git_inflate_end(&st->z);
-	munmap(st->mapped, st->mapsize);
+	munmap(mapped, mapsize);
 	free(st);
 	return -1;
 }
diff --git a/pack-revindex.c b/pack-revindex.c
index 56cd803a6798d5..1fe0afe89907c5 100644
--- a/pack-revindex.c
+++ b/pack-revindex.c
@@ -277,6 +277,10 @@ int load_pack_revindex_from_disk(struct packed_git *p)
 {
 	char *revindex_name;
 	int ret;
+
+	if (p->revindex_data)
+		return 0;
+
 	if (open_pack_index(p))
 		return -1;
 
diff --git a/patch-ids.c b/patch-ids.c
index a5683b462c6e76..1fbc88cbec874e 100644
--- a/patch-ids.c
+++ b/patch-ids.c
@@ -41,7 +41,14 @@ static int patch_id_neq(const void *cmpfn_data,
 			const struct hashmap_entry *entry_or_key,
 			const void *keydata UNUSED)
 {
-	/* NEEDSWORK: const correctness? */
+	/*
+	 * We drop the 'const' modifier here intentionally.
+	 *
+	 * Even though eptr and entry_or_key are const, we want to
+	 * lazily compute their .patch_id members; see b3dfeebb (rebase:
+	 * avoid computing unnecessary patch IDs, 2016-07-29). So we cast
+	 * the constness away with container_of().
+	 */
 	struct diff_options *opt = (void *)cmpfn_data;
 	struct patch_id *a, *b;
 
diff --git a/setup.c b/setup.c
index 393b970ae4f96d..7ec4427368a2a7 100644
--- a/setup.c
+++ b/setup.c
@@ -920,8 +920,10 @@ int verify_repository_format(const struct repository_format *format,
 void read_gitfile_error_die(int error_code, const char *path, const char *dir)
 {
 	switch (error_code) {
-	case READ_GITFILE_ERR_STAT_FAILED:
 	case READ_GITFILE_ERR_NOT_A_FILE:
+	case READ_GITFILE_ERR_STAT_FAILED:
+	case READ_GITFILE_ERR_MISSING:
+	case READ_GITFILE_ERR_IS_A_DIR:
 		/* non-fatal; follow return path */
 		break;
 	case READ_GITFILE_ERR_OPEN_FAILED:
@@ -964,8 +966,14 @@ const char *read_gitfile_gently(const char *path, int *return_error_code)
 	static struct strbuf realpath = STRBUF_INIT;
 
 	if (stat(path, &st)) {
-		/* NEEDSWORK: discern between ENOENT vs other errors */
-		error_code = READ_GITFILE_ERR_STAT_FAILED;
+		if (errno == ENOENT || errno == ENOTDIR)
+			error_code = READ_GITFILE_ERR_MISSING;
+		else
+			error_code = READ_GITFILE_ERR_STAT_FAILED;
+		goto cleanup_return;
+	}
+	if (S_ISDIR(st.st_mode)) {
+		error_code = READ_GITFILE_ERR_IS_A_DIR;
 		goto cleanup_return;
 	}
 	if (!S_ISREG(st.st_mode)) {
@@ -1601,20 +1609,37 @@ static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
 		if (offset > min_offset)
 			strbuf_addch(dir, '/');
 		strbuf_addstr(dir, DEFAULT_GIT_DIR_ENVIRONMENT);
-		gitdirenv = read_gitfile_gently(dir->buf, die_on_error ?
-						NULL : &error_code);
+		gitdirenv = read_gitfile_gently(dir->buf, &error_code);
 		if (!gitdirenv) {
-			if (die_on_error ||
-			    error_code == READ_GITFILE_ERR_NOT_A_FILE) {
-				/* NEEDSWORK: fail if .git is not file nor dir */
+			switch (error_code) {
+			case READ_GITFILE_ERR_MISSING:
+				/* no .git in this directory, move on */
+				break;
+			case READ_GITFILE_ERR_IS_A_DIR:
 				if (is_git_directory(dir->buf)) {
 					gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 					gitdir_path = xstrdup(dir->buf);
 				}
-			} else if (error_code != READ_GITFILE_ERR_STAT_FAILED)
-				return GIT_DIR_INVALID_GITFILE;
-		} else
+				break;
+			case READ_GITFILE_ERR_STAT_FAILED:
+				if (die_on_error)
+					die(_("error reading '%s'"), dir->buf);
+				else
+					return GIT_DIR_INVALID_GITFILE;
+			case READ_GITFILE_ERR_NOT_A_FILE:
+				if (die_on_error)
+					die(_("not a regular file: '%s'"), dir->buf);
+				else
+					return GIT_DIR_INVALID_GITFILE;
+			default:
+				if (die_on_error)
+					read_gitfile_error_die(error_code, dir->buf, NULL);
+				else
+					return GIT_DIR_INVALID_GITFILE;
+			}
+		} else {
 			gitfile = xstrdup(dir->buf);
+		}
 		/*
 		 * Earlier, we tentatively added DEFAULT_GIT_DIR_ENVIRONMENT
 		 * to check that directory for a repository.
diff --git a/setup.h b/setup.h
index bcb16b0b4a6662..80bc6e5f078af8 100644
--- a/setup.h
+++ b/setup.h
@@ -36,6 +36,8 @@ int is_nonbare_repository_dir(struct strbuf *path);
 #define READ_GITFILE_ERR_NO_PATH 6
 #define READ_GITFILE_ERR_NOT_A_REPO 7
 #define READ_GITFILE_ERR_TOO_LARGE 8
+#define READ_GITFILE_ERR_MISSING 9
+#define READ_GITFILE_ERR_IS_A_DIR 10
 void read_gitfile_error_die(int error_code, const char *path, const char *dir);
 const char *read_gitfile_gently(const char *path, int *return_error_code);
 #define read_gitfile(path) read_gitfile_gently((path), NULL)
diff --git a/submodule.c b/submodule.c
index 4f9aaa2c75679b..cd879a5cfe73ec 100644
--- a/submodule.c
+++ b/submodule.c
@@ -2559,7 +2559,7 @@ void absorb_git_dir_into_superproject(const char *path,
 		const struct submodule *sub;
 		struct strbuf sub_gitdir = STRBUF_INIT;
 
-		if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
+		if (err_code == READ_GITFILE_ERR_MISSING) {
 			/* unpopulated as expected */
 			strbuf_release(&gitdir);
 			return;
diff --git a/t/meson.build b/t/meson.build
index f66a73f8a07d93..9b2fa4dee807d6 100644
--- a/t/meson.build
+++ b/t/meson.build
@@ -81,6 +81,7 @@ integration_tests = [
   't0006-date.sh',
   't0007-git-var.sh',
   't0008-ignores.sh',
+  't0009-git-dir-validation.sh',
   't0010-racy-git.sh',
   't0012-help.sh',
   't0013-sha1dc.sh',
diff --git a/t/t0009-git-dir-validation.sh b/t/t0009-git-dir-validation.sh
new file mode 100755
index 00000000000000..33d21ed9ea1061
--- /dev/null
+++ b/t/t0009-git-dir-validation.sh
@@ -0,0 +1,77 @@
+#!/bin/sh
+
+test_description='setup: validation of .git file/directory types
+
+Verify that setup_git_directory() correctly handles:
+1. Valid .git directories (including symlinks to them).
+2. Invalid .git files (FIFOs, sockets) by erroring out.
+3. Invalid .git files (garbage) by erroring out.
+'
+
+. ./test-lib.sh
+
+test_expect_success 'setup: create parent git repository' '
+	git init parent &&
+	test_commit -C parent "root-commit"
+'
+
+test_expect_success SYMLINKS 'setup: .git as a symlink to a directory is valid' '
+	test_when_finished "rm -rf parent/link-to-dir" &&
+	mkdir -p parent/link-to-dir &&
+	(
+		cd parent/link-to-dir &&
+		git init real-repo &&
+		ln -s real-repo/.git .git &&
+		git rev-parse --git-dir >actual &&
+		echo .git >expect &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success PIPE 'setup: .git as a FIFO (named pipe) is rejected' '
+	test_when_finished "rm -rf parent/fifo-trap" &&
+	mkdir -p parent/fifo-trap &&
+	(
+		cd parent/fifo-trap &&
+		mkfifo .git &&
+		test_must_fail git rev-parse --git-dir 2>stderr &&
+		grep "not a regular file" stderr
+	)
+'
+
+test_expect_success SYMLINKS,PIPE 'setup: .git as a symlink to a FIFO is rejected' '
+	test_when_finished "rm -rf parent/symlink-fifo-trap" &&
+	mkdir -p parent/symlink-fifo-trap &&
+	(
+		cd parent/symlink-fifo-trap &&
+		mkfifo target-fifo &&
+		ln -s target-fifo .git &&
+		test_must_fail git rev-parse --git-dir 2>stderr &&
+		grep "not a regular file" stderr
+	)
+'
+
+test_expect_success 'setup: .git with garbage content is rejected' '
+	test_when_finished "rm -rf parent/garbage-trap" &&
+	mkdir -p parent/garbage-trap &&
+	(
+		cd parent/garbage-trap &&
+		echo "garbage" >.git &&
+		test_must_fail git rev-parse --git-dir 2>stderr &&
+		grep "invalid gitfile format" stderr
+	)
+'
+
+test_expect_success 'setup: .git as an empty directory is ignored' '
+	test_when_finished "rm -rf parent/empty-dir" &&
+	mkdir -p parent/empty-dir &&
+	(
+		cd parent/empty-dir &&
+		git rev-parse --git-dir >expect &&
+		mkdir .git &&
+		git rev-parse --git-dir >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_done
diff --git a/t/t1901-repo-structure.sh b/t/t1901-repo-structure.sh
index a67b38ab178125..98921ce1cbb66f 100755
--- a/t/t1901-repo-structure.sh
+++ b/t/t1901-repo-structure.sh
@@ -27,31 +27,43 @@ test_expect_success 'empty repository' '
 	(
 		cd repo &&
 		cat >expect <<-\EOF &&
-		| Repository structure | Value  |
-		| -------------------- | ------ |
-		| * References         |        |
-		|   * Count            |    0   |
-		|     * Branches       |    0   |
-		|     * Tags           |    0   |
-		|     * Remotes        |    0   |
-		|     * Others         |    0   |
-		|                      |        |
-		| * Reachable objects  |        |
-		|   * Count            |    0   |
-		|     * Commits        |    0   |
-		|     * Trees          |    0   |
-		|     * Blobs          |    0   |
-		|     * Tags           |    0   |
-		|   * Inflated size    |    0 B |
-		|     * Commits        |    0 B |
-		|     * Trees          |    0 B |
-		|     * Blobs          |    0 B |
-		|     * Tags           |    0 B |
-		|   * Disk size        |    0 B |
-		|     * Commits        |    0 B |
-		|     * Trees          |    0 B |
-		|     * Blobs          |    0 B |
-		|     * Tags           |    0 B |
+		| Repository structure      | Value  |
+		| ------------------------- | ------ |
+		| * References              |        |
+		|   * Count                 |    0   |
+		|     * Branches            |    0   |
+		|     * Tags                |    0   |
+		|     * Remotes             |    0   |
+		|     * Others              |    0   |
+		|                           |        |
+		| * Reachable objects       |        |
+		|   * Count                 |    0   |
+		|     * Commits             |    0   |
+		|     * Trees               |    0   |
+		|     * Blobs               |    0   |
+		|     * Tags                |    0   |
+		|   * Inflated size         |    0 B |
+		|     * Commits             |    0 B |
+		|     * Trees               |    0 B |
+		|     * Blobs               |    0 B |
+		|     * Tags                |    0 B |
+		|   * Disk size             |    0 B |
+		|     * Commits             |    0 B |
+		|     * Trees               |    0 B |
+		|     * Blobs               |    0 B |
+		|     * Tags                |    0 B |
+		|                           |        |
+		| * Largest objects         |        |
+		|   * Commits               |        |
+		|     * Maximum size        |    0 B |
+		|     * Maximum parents     |    0   |
+		|   * Trees                 |        |
+		|     * Maximum size        |    0 B |
+		|     * Maximum entries     |    0   |
+		|   * Blobs                 |        |
+		|     * Maximum size        |    0 B |
+		|   * Tags                  |        |
+		|     * Maximum size        |    0 B |
 		EOF
 
 		git repo structure >out 2>err &&
@@ -79,31 +91,50 @@ test_expect_success SHA1 'repository with references and objects' '
 		# git-rev-list(1) --disk-usage=human option printing the full
 		# "byte/bytes" unit string instead of just "B".
 		cat >expect <<-EOF &&
-		| Repository structure | Value      |
-		| -------------------- | ---------- |
-		| * References         |            |
-		|   * Count            |      4     |
-		|     * Branches       |      1     |
-		|     * Tags           |      1     |
-		|     * Remotes        |      1     |
-		|     * Others         |      1     |
-		|                      |            |
-		| * Reachable objects  |            |
-		|   * Count            |   3.02 k   |
-		|     * Commits        |   1.01 k   |
-		|     * Trees          |   1.01 k   |
-		|     * Blobs          |   1.01 k   |
-		|     * Tags           |      1     |
-		|   * Inflated size    |  16.03 MiB |
-		|     * Commits        | 217.92 KiB |
-		|     * Trees          |  15.81 MiB |
-		|     * Blobs          |  11.68 KiB |
-		|     * Tags           |    132 B   |
-		|   * Disk size        | $(object_type_disk_usage all true) |
-		|     * Commits        | $(object_type_disk_usage commit true) |
-		|     * Trees          | $(object_type_disk_usage tree true) |
-		|     * Blobs          |  $(object_type_disk_usage blob true) |
-		|     * Tags           |    $(object_type_disk_usage tag) B   |
+		| Repository structure      | Value      |
+		| ------------------------- | ---------- |
+		| * References              |            |
+		|   * Count                 |      4     |
+		|     * Branches            |      1     |
+		|     * Tags                |      1     |
+		|     * Remotes             |      1     |
+		|     * Others              |      1     |
+		|                           |            |
+		| * Reachable objects       |            |
+		|   * Count                 |   3.02 k   |
+		|     * Commits             |   1.01 k   |
+		|     * Trees               |   1.01 k   |
+		|     * Blobs               |   1.01 k   |
+		|     * Tags                |      1     |
+		|   * Inflated size         |  16.03 MiB |
+		|     * Commits             | 217.92 KiB |
+		|     * Trees               |  15.81 MiB |
+		|     * Blobs               |  11.68 KiB |
+		|     * Tags                |    132 B   |
+		|   * Disk size             | $(object_type_disk_usage all true) |
+		|     * Commits             | $(object_type_disk_usage commit true) |
+		|     * Trees               | $(object_type_disk_usage tree true) |
+		|     * Blobs               |  $(object_type_disk_usage blob true) |
+		|     * Tags                |    $(object_type_disk_usage tag) B   |
+		|                           |            |
+		| * Largest objects         |            |
+		|   * Commits               |            |
+		|     * Maximum size    [1] |    223 B   |
+		|     * Maximum parents [2] |      1     |
+		|   * Trees                 |            |
+		|     * Maximum size    [3] |  32.29 KiB |
+		|     * Maximum entries [4] |   1.01 k   |
+		|   * Blobs                 |            |
+		|     * Maximum size    [5] |     13 B   |
+		|   * Tags                  |            |
+		|     * Maximum size    [6] |    132 B   |
+
+		[1] 0dc91eb18580102a3a216c8bfecedeba2b9f9b9a
+		[2] 0dc91eb18580102a3a216c8bfecedeba2b9f9b9a
+		[3] 60665251ab71dbd8c18d9bf2174f4ee0d58aa06c
+		[4] 60665251ab71dbd8c18d9bf2174f4ee0d58aa06c
+		[5] 97d808e45116bf02103490294d3d46dad7a2ac62
+		[6] 4dae4f5954f5e6feb3577cfb1b181daa3fd3afd2
 		EOF
 
 		git repo structure >out 2>err &&
@@ -138,6 +169,18 @@ test_expect_success SHA1 'lines and nul format' '
 		objects.trees.disk_size=$(object_type_disk_usage tree)
 		objects.blobs.disk_size=$(object_type_disk_usage blob)
 		objects.tags.disk_size=$(object_type_disk_usage tag)
+		objects.commits.max_size=221
+		objects.commits.max_size_oid=de3508174b5c2ace6993da67cae9be9069e2df39
+		objects.trees.max_size=1335
+		objects.trees.max_size_oid=09931deea9d81ec21300d3e13c74412f32eacec5
+		objects.blobs.max_size=11
+		objects.blobs.max_size_oid=eaeeedced46482bd4281fda5a5f05ce24854151f
+		objects.tags.max_size=132
+		objects.tags.max_size_oid=1ee0f2b16ea37d895dbe9dbd76cd2ac70446176c
+		objects.commits.max_parents=1
+		objects.commits.max_parents_oid=de3508174b5c2ace6993da67cae9be9069e2df39
+		objects.trees.max_entries=42
+		objects.trees.max_entries_oid=09931deea9d81ec21300d3e13c74412f32eacec5
 		EOF
 
 		git repo structure --format=lines >out 2>err &&
diff --git a/t/t3310-notes-merge-manual-resolve.sh b/t/t3310-notes-merge-manual-resolve.sh
index f0054b0a39c541..0bb366fdb8fce1 100755
--- a/t/t3310-notes-merge-manual-resolve.sh
+++ b/t/t3310-notes-merge-manual-resolve.sh
@@ -227,7 +227,8 @@ test_expect_success 'merge z into m (== y) with default ("manual") resolver => C
 	# Verify that current notes tree (pre-merge) has not changed (m == y)
 	verify_notes y &&
 	verify_notes m &&
-	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)"
+	git rev-parse refs/notes/m >actual &&
+	test_cmp pre_merge_y actual
 '
 
 cat <<EOF | sort >expect_notes_z
@@ -375,8 +376,10 @@ EOF
 	git notes merge --commit &&
 	notes_merge_files_gone &&
 	# Merge commit has pre-merge y and pre-merge z as parents
-	test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
-	test "$(git rev-parse refs/notes/m^2)" = "$(cat pre_merge_z)" &&
+	git rev-parse refs/notes/m^1 >actual &&
+	test_cmp pre_merge_y actual &&
+	git rev-parse refs/notes/m^2 >actual &&
+	test_cmp pre_merge_z actual &&
 	# Merge commit mentions the notes refs merged
 	git log -1 --format=%B refs/notes/m > merge_commit_msg &&
 	grep -q refs/notes/m merge_commit_msg &&
@@ -428,14 +431,16 @@ test_expect_success 'redo merge of z into m (== y) with default ("manual") resol
 	# Verify that current notes tree (pre-merge) has not changed (m == y)
 	verify_notes y &&
 	verify_notes m &&
-	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)"
+	git rev-parse refs/notes/m >actual &&
+	test_cmp pre_merge_y actual
 '
 
 test_expect_success 'abort notes merge' '
 	git notes merge --abort &&
 	notes_merge_files_gone &&
 	# m has not moved (still == y)
-	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)" &&
+	git rev-parse refs/notes/m >actual &&
+	test_cmp pre_merge_y actual &&
 	# Verify that other notes refs has not changed (w, x, y and z)
 	verify_notes w &&
 	verify_notes x &&
@@ -460,7 +465,8 @@ test_expect_success 'redo merge of z into m (== y) with default ("manual") resol
 	# Verify that current notes tree (pre-merge) has not changed (m == y)
 	verify_notes y &&
 	verify_notes m &&
-	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)"
+	git rev-parse refs/notes/m >actual &&
+	test_cmp pre_merge_y actual
 '
 
 cat <<EOF | sort >expect_notes_m
@@ -500,8 +506,10 @@ EOF
 	git notes merge --commit &&
 	notes_merge_files_gone &&
 	# Merge commit has pre-merge y and pre-merge z as parents
-	test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
-	test "$(git rev-parse refs/notes/m^2)" = "$(cat pre_merge_z)" &&
+	git rev-parse refs/notes/m^1 >actual &&
+	test_cmp pre_merge_y actual &&
+	git rev-parse refs/notes/m^2 >actual &&
+	test_cmp pre_merge_z actual &&
 	# Merge commit mentions the notes refs merged
 	git log -1 --format=%B refs/notes/m > merge_commit_msg &&
 	grep -q refs/notes/m merge_commit_msg &&
@@ -539,7 +547,8 @@ test_expect_success 'redo merge of z into m (== y) with default ("manual") resol
 	# Verify that current notes tree (pre-merge) has not changed (m == y)
 	verify_notes y &&
 	verify_notes m &&
-	test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)"
+	git rev-parse refs/notes/m >actual &&
+	test_cmp pre_merge_y actual
 '
 
 cp expect_notes_w expect_notes_m
@@ -548,7 +557,7 @@ cp expect_log_w expect_log_m
 test_expect_success 'reset notes ref m to somewhere else (w)' '
 	git update-ref refs/notes/m refs/notes/w &&
 	verify_notes m &&
-	test "$(git rev-parse refs/notes/m)" = "$(git rev-parse refs/notes/w)"
+	test_cmp_rev refs/notes/m refs/notes/w
 '
 
 test_expect_success 'fail to finalize conflicting merge if underlying ref has moved in the meantime (m != NOTES_MERGE_PARTIAL^1)' '
@@ -569,13 +578,15 @@ EOF
 	test_path_is_file .git/NOTES_MERGE_WORKTREE/$commit_sha3 &&
 	test_path_is_file .git/NOTES_MERGE_WORKTREE/$commit_sha4 &&
 	# Refs are unchanged
-	test "$(git rev-parse refs/notes/m)" = "$(git rev-parse refs/notes/w)" &&
-	test "$(git rev-parse refs/notes/y)" = "$(git rev-parse NOTES_MERGE_PARTIAL^1)" &&
-	test "$(git rev-parse refs/notes/m)" != "$(git rev-parse NOTES_MERGE_PARTIAL^1)" &&
+	test_cmp_rev refs/notes/m refs/notes/w &&
+	test_cmp_rev refs/notes/y NOTES_MERGE_PARTIAL^1 &&
+	test_cmp_rev ! refs/notes/m NOTES_MERGE_PARTIAL^1 &&
 	# Mention refs/notes/m, and its current and expected value in output
 	test_grep -q "refs/notes/m" output &&
-	test_grep -q "$(git rev-parse refs/notes/m)" output &&
-	test_grep -q "$(git rev-parse NOTES_MERGE_PARTIAL^1)" output &&
+	oid=$(git rev-parse refs/notes/m) &&
+	test_grep -q "$oid" output &&
+	oid=$(git rev-parse NOTES_MERGE_PARTIAL^1) &&
+	test_grep -q "$oid" output &&
 	# Verify that other notes refs has not changed (w, x, y and z)
 	verify_notes w &&
 	verify_notes x &&
@@ -587,7 +598,7 @@ test_expect_success 'resolve situation by aborting the notes merge' '
 	git notes merge --abort &&
 	notes_merge_files_gone &&
 	# m has not moved (still == w)
-	test "$(git rev-parse refs/notes/m)" = "$(git rev-parse refs/notes/w)" &&
+	test_cmp_rev refs/notes/m refs/notes/w &&
 	# Verify that other notes refs has not changed (w, x, y and z)
 	verify_notes w &&
 	verify_notes x &&
@@ -606,8 +617,8 @@ test_expect_success 'switch cwd before committing notes merge' '
 	test_must_fail git notes merge refs/notes/other &&
 	(
 		cd .git/NOTES_MERGE_WORKTREE &&
-		echo "foo" > $(git rev-parse HEAD) &&
-		echo "bar" >> $(git rev-parse HEAD) &&
+		oid=$(git rev-parse HEAD) &&
+		test_write_lines foo bar >"$oid" &&
 		git notes merge --commit
 	) &&
 	git notes show HEAD > actual_notes &&
diff --git a/worktree.c b/worktree.c
index e9ff6e6ef2eb58..6552e300536cc6 100644
--- a/worktree.c
+++ b/worktree.c
@@ -673,7 +673,8 @@ static void repair_gitfile(struct worktree *wt,
 		}
 	}
 
-	if (err == READ_GITFILE_ERR_NOT_A_FILE)
+	if (err == READ_GITFILE_ERR_NOT_A_FILE ||
+		err == READ_GITFILE_ERR_IS_A_DIR)
 		fn(1, wt->path, _(".git is not a file"), cb_data);
 	else if (err)
 		repair = _(".git file broken");
@@ -853,7 +854,8 @@ void repair_worktree_at_path(const char *path,
 			strbuf_addstr(&backlink, dotgit_contents);
 			strbuf_realpath_forgiving(&backlink, backlink.buf, 0);
 		}
-	} else if (err == READ_GITFILE_ERR_NOT_A_FILE) {
+	} else if (err == READ_GITFILE_ERR_NOT_A_FILE ||
+			err == READ_GITFILE_ERR_IS_A_DIR) {
 		fn(1, dotgit.buf, _("unable to locate repository; .git is not a file"), cb_data);
 		goto done;
 	} else if (err == READ_GITFILE_ERR_NOT_A_REPO) {
diff --git a/wt-status.c b/wt-status.c
index 543000311fd615..479ccc3304bc33 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -150,11 +150,11 @@ void wt_status_prepare(struct repository *r, struct wt_status *s)
 	s->show_untracked_files = SHOW_NORMAL_UNTRACKED_FILES;
 	s->use_color = GIT_COLOR_UNKNOWN;
 	s->relative_paths = 1;
-	s->branch = refs_resolve_refdup(get_main_ref_store(the_repository),
+	s->branch = refs_resolve_refdup(get_main_ref_store(r),
 					"HEAD", 0, NULL, NULL);
 	s->reference = "HEAD";
 	s->fp = stdout;
-	s->index_file = repo_get_index_file(the_repository);
+	s->index_file = repo_get_index_file(r);
 	s->change.strdup_strings = 1;
 	s->untracked.strdup_strings = 1;
 	s->ignored.strdup_strings = 1;
@@ -670,7 +670,7 @@ static void wt_status_collect_changes_index(struct wt_status *s)
 
 	repo_init_revisions(s->repo, &rev, NULL);
 	memset(&opt, 0, sizeof(opt));
-	opt.def = s->is_initial ? empty_tree_oid_hex(the_repository->hash_algo) : s->reference;
+	opt.def = s->is_initial ? empty_tree_oid_hex(s->repo->hash_algo) : s->reference;
 	setup_revisions(0, NULL, &rev, &opt);
 
 	rev.diffopt.flags.override_submodule_config = 1;
@@ -1008,17 +1008,17 @@ static int stash_count_refs(const char *refname UNUSED,
 	return 0;
 }
 
-static int count_stash_entries(void)
+static int count_stash_entries(struct repository *r)
 {
 	int n = 0;
-	refs_for_each_reflog_ent(get_main_ref_store(the_repository),
+	refs_for_each_reflog_ent(get_main_ref_store(r),
 				 "refs/stash", stash_count_refs, &n);
 	return n;
 }
 
 static void wt_longstatus_print_stash_summary(struct wt_status *s)
 {
-	int stash_count = count_stash_entries();
+	int stash_count = count_stash_entries(s->repo);
 
 	if (stash_count > 0)
 		status_printf_ln(s, GIT_COLOR_NORMAL,
@@ -1170,7 +1170,7 @@ static void wt_longstatus_print_verbose(struct wt_status *s)
 	rev.diffopt.ita_invisible_in_index = 1;
 
 	memset(&opt, 0, sizeof(opt));
-	opt.def = s->is_initial ? empty_tree_oid_hex(the_repository->hash_algo) : s->reference;
+	opt.def = s->is_initial ? empty_tree_oid_hex(s->repo->hash_algo) : s->reference;
 	setup_revisions(0, NULL, &rev, &opt);
 
 	rev.diffopt.output_format |= DIFF_FORMAT_PATCH;
@@ -1311,10 +1311,10 @@ static void show_am_in_progress(struct wt_status *s,
 	wt_longstatus_print_trailer(s);
 }
 
-static char *read_line_from_git_path(const char *filename)
+static char *read_line_from_git_path(struct repository *r, const char *filename)
 {
 	struct strbuf buf = STRBUF_INIT;
-	FILE *fp = fopen_or_warn(repo_git_path_append(the_repository, &buf,
+	FILE *fp = fopen_or_warn(repo_git_path_append(r, &buf,
 						      "%s", filename), "r");
 
 	if (!fp) {
@@ -1341,16 +1341,16 @@ static int split_commit_in_progress(struct wt_status *s)
 	    !s->branch || strcmp(s->branch, "HEAD"))
 		return 0;
 
-	if (refs_read_ref_full(get_main_ref_store(the_repository), "HEAD", RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+	if (refs_read_ref_full(get_main_ref_store(s->repo), "HEAD", RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
 			       &head_oid, &head_flags) ||
-	    refs_read_ref_full(get_main_ref_store(the_repository), "ORIG_HEAD", RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
+	    refs_read_ref_full(get_main_ref_store(s->repo), "ORIG_HEAD", RESOLVE_REF_READING | RESOLVE_REF_NO_RECURSE,
 			       &orig_head_oid, &orig_head_flags))
 		return 0;
 	if (head_flags & REF_ISSYMREF || orig_head_flags & REF_ISSYMREF)
 		return 0;
 
-	rebase_amend = read_line_from_git_path("rebase-merge/amend");
-	rebase_orig_head = read_line_from_git_path("rebase-merge/orig-head");
+	rebase_amend = read_line_from_git_path(s->repo, "rebase-merge/amend");
+	rebase_orig_head = read_line_from_git_path(s->repo, "rebase-merge/orig-head");
 
 	if (!rebase_amend || !rebase_orig_head)
 		; /* fall through, no split in progress */
@@ -1374,7 +1374,7 @@ static int split_commit_in_progress(struct wt_status *s)
  * The function assumes that the line does not contain useless spaces
  * before or after the command.
  */
-static void abbrev_oid_in_line(struct strbuf *line)
+static void abbrev_oid_in_line(struct repository *r, struct strbuf *line)
 {
 	struct string_list split = STRING_LIST_INIT_DUP;
 	struct object_id oid;
@@ -1386,7 +1386,7 @@ static void abbrev_oid_in_line(struct strbuf *line)
 		return;
 
 	if ((2 <= string_list_split(&split, line->buf, " ", 2)) &&
-	    !repo_get_oid(the_repository, split.items[1].string, &oid)) {
+	    !repo_get_oid(r, split.items[1].string, &oid)) {
 		strbuf_reset(line);
 		strbuf_addf(line, "%s ", split.items[0].string);
 		strbuf_add_unique_abbrev(line, &oid, DEFAULT_ABBREV);
@@ -1396,10 +1396,10 @@ static void abbrev_oid_in_line(struct strbuf *line)
 	string_list_clear(&split, 0);
 }
 
-static int read_rebase_todolist(const char *fname, struct string_list *lines)
+static int read_rebase_todolist(struct repository *r, const char *fname, struct string_list *lines)
 {
 	struct strbuf buf = STRBUF_INIT;
-	FILE *f = fopen(repo_git_path_append(the_repository, &buf, "%s", fname), "r");
+	FILE *f = fopen(repo_git_path_append(r, &buf, "%s", fname), "r");
 	int ret;
 
 	if (!f) {
@@ -1408,7 +1408,7 @@ static int read_rebase_todolist(const char *fname, struct string_list *lines)
 			goto out;
 		}
 		die_errno("Could not open file %s for reading",
-			  repo_git_path_replace(the_repository, &buf, "%s", fname));
+			  repo_git_path_replace(r, &buf, "%s", fname));
 	}
 	while (!strbuf_getline_lf(&buf, f)) {
 		if (starts_with(buf.buf, comment_line_str))
@@ -1416,7 +1416,7 @@ static int read_rebase_todolist(const char *fname, struct string_list *lines)
 		strbuf_trim(&buf);
 		if (!buf.len)
 			continue;
-		abbrev_oid_in_line(&buf);
+		abbrev_oid_in_line(r, &buf);
 		string_list_append(lines, buf.buf);
 	}
 	fclose(f);
@@ -1437,8 +1437,8 @@ static void show_rebase_information(struct wt_status *s,
 		struct string_list have_done = STRING_LIST_INIT_DUP;
 		struct string_list yet_to_do = STRING_LIST_INIT_DUP;
 
-		read_rebase_todolist("rebase-merge/done", &have_done);
-		if (read_rebase_todolist("rebase-merge/git-rebase-todo",
+		read_rebase_todolist(s->repo, "rebase-merge/done", &have_done);
+		if (read_rebase_todolist(s->repo, "rebase-merge/git-rebase-todo",
 					 &yet_to_do))
 			status_printf_ln(s, color,
 				_("git-rebase-todo is missing."));
@@ -1456,7 +1456,7 @@ static void show_rebase_information(struct wt_status *s,
 				i++)
 				status_printf_ln(s, color, "   %s", have_done.items[i].string);
 			if (have_done.nr > nr_lines_to_show && s->hints) {
-				char *path = repo_git_path(the_repository, "rebase-merge/done");
+				char *path = repo_git_path(s->repo, "rebase-merge/done");
 				status_printf_ln(s, color,
 					_("  (see more in file %s)"), path);
 				free(path);
@@ -1558,7 +1558,7 @@ static void show_cherry_pick_in_progress(struct wt_status *s,
 	else
 		status_printf_ln(s, color,
 			_("You are currently cherry-picking commit %s."),
-			repo_find_unique_abbrev(the_repository, &s->state.cherry_pick_head_oid,
+			repo_find_unique_abbrev(s->repo, &s->state.cherry_pick_head_oid,
 						DEFAULT_ABBREV));
 
 	if (s->hints) {
@@ -1588,7 +1588,7 @@ static void show_revert_in_progress(struct wt_status *s,
 	else
 		status_printf_ln(s, color,
 			_("You are currently reverting commit %s."),
-			repo_find_unique_abbrev(the_repository, &s->state.revert_head_oid,
+			repo_find_unique_abbrev(s->repo, &s->state.revert_head_oid,
 						DEFAULT_ABBREV));
 	if (s->hints) {
 		if (has_unmerged(s))
@@ -1715,7 +1715,7 @@ static void wt_status_get_detached_from(struct repository *r,
 	char *ref = NULL;
 
 	strbuf_init(&cb.buf, 0);
-	if (refs_for_each_reflog_ent_reverse(get_main_ref_store(the_repository), "HEAD", grab_1st_switch, &cb) <= 0) {
+	if (refs_for_each_reflog_ent_reverse(get_main_ref_store(r), "HEAD", grab_1st_switch, &cb) <= 0) {
 		strbuf_release(&cb.buf);
 		return;
 	}
@@ -1848,10 +1848,10 @@ void wt_status_get_state(struct repository *r,
 	if (!sequencer_get_last_command(r, &action)) {
 		if (action == REPLAY_PICK && !state->cherry_pick_in_progress) {
 			state->cherry_pick_in_progress = 1;
-			oidcpy(&state->cherry_pick_head_oid, null_oid(the_hash_algo));
+			oidcpy(&state->cherry_pick_head_oid, null_oid(r->hash_algo));
 		} else if (action == REPLAY_REVERT && !state->revert_in_progress) {
 			state->revert_in_progress = 1;
-			oidcpy(&state->revert_head_oid, null_oid(the_hash_algo));
+			oidcpy(&state->revert_head_oid, null_oid(r->hash_algo));
 		}
 	}
 	if (get_detached_from)
@@ -2134,7 +2134,7 @@ static void wt_shortstatus_print_tracking(struct wt_status *s)
 		upstream_is_gone = 1;
 	}
 
-	short_base = refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),
+	short_base = refs_shorten_unambiguous_ref(get_main_ref_store(s->repo),
 						  base, 0);
 	color_fprintf(s->fp, header_color, "...");
 	color_fprintf(s->fp, branch_color_remote, "%s", short_base);
@@ -2268,7 +2268,7 @@ static void wt_porcelain_v2_print_tracking(struct wt_status *s)
 		ab_info = stat_tracking_info(branch, &nr_ahead, &nr_behind,
 					     &base, 0, s->ahead_behind_flags);
 		if (base) {
-			base = refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),
+			base = refs_shorten_unambiguous_ref(get_main_ref_store(s->repo),
 							    base, 0);
 			fprintf(s->fp, "# branch.upstream %s%c", base, eol);
 			free((char *)base);
@@ -2294,7 +2294,7 @@ static void wt_porcelain_v2_print_tracking(struct wt_status *s)
  */
 static void wt_porcelain_v2_print_stash(struct wt_status *s)
 {
-	int stash_count = count_stash_entries();
+	int stash_count = count_stash_entries(s->repo);
 	char eol = s->null_termination ? '\0' : '\n';
 
 	if (stash_count > 0)
@@ -2665,7 +2665,7 @@ int has_uncommitted_changes(struct repository *r,
 		 * We have no head (or it's corrupt); use the empty tree,
 		 * which will complain if the index is non-empty.
 		 */
-		struct tree *tree = lookup_tree(r, the_hash_algo->empty_tree);
+		struct tree *tree = lookup_tree(r, r->hash_algo->empty_tree);
 		add_pending_object(&rev_info, &tree->object, "");
 	}