diff --git a/Documentation/git-pack-refs.txt b/Documentation/git-pack-refs.txt
index f131677..154081f 100644
--- a/Documentation/git-pack-refs.txt
+++ b/Documentation/git-pack-refs.txt
@@ -33,8 +33,8 @@
 `$GIT_DIR/refs` directory hierarchy.
 
 A recommended practice to deal with a repository with too many
-refs is to pack its refs with `--all --prune` once, and
-occasionally run `git pack-refs --prune`.  Tags are by
+refs is to pack its refs with `--all` once, and
+occasionally run `git pack-refs`.  Tags are by
 definition stationary and are not expected to change.  Branch
 heads will be packed with the initial `pack-refs --all`, but
 only the currently active branch heads will become unpacked,
diff --git a/Documentation/git-prune.txt b/Documentation/git-prune.txt
index 80d01b0..bf82410 100644
--- a/Documentation/git-prune.txt
+++ b/Documentation/git-prune.txt
@@ -59,7 +59,7 @@
 `.git/objects/info/alternates`:
 
 ------------
-$ git prune $(cd ../another && $(git rev-parse --all))
+$ git prune $(cd ../another && git rev-parse --all)
 ------------
 
 Notes
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 0e64b41..163ce6c 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -150,7 +150,9 @@
 		if (!data->mark_query)
 			strbuf_addstr(sb, sha1_to_hex(data->sha1));
 	} else if (is_atom("objecttype", atom, len)) {
-		if (!data->mark_query)
+		if (data->mark_query)
+			data->info.typep = &data->type;
+		else
 			strbuf_addstr(sb, typename(data->type));
 	} else if (is_atom("objectsize", atom, len)) {
 		if (data->mark_query)
@@ -229,8 +231,7 @@
 		return 0;
 	}
 
-	data->type = sha1_object_info_extended(data->sha1, &data->info);
-	if (data->type <= 0) {
+	if (sha1_object_info_extended(data->sha1, &data->info) < 0) {
 		printf("%s missing\n", obj_name);
 		fflush(stdout);
 		return 0;
@@ -266,6 +267,15 @@
 	strbuf_expand(&buf, opt->format, expand_format, &data);
 	data.mark_query = 0;
 
+	/*
+	 * We are going to call get_sha1 on a potentially very large number of
+	 * objects. In most large cases, these will be actual object sha1s. The
+	 * cost to double-check that each one is not also a ref (just so we can
+	 * warn) ends up dwarfing the actual cost of the object lookups
+	 * themselves. We can work around it by just turning off the warning.
+	 */
+	warn_on_object_refname_ambiguity = 0;
+
 	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
 		char *p;
 		int error;
diff --git a/builtin/commit.c b/builtin/commit.c
index 65cf2a7..003bd7d 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -534,7 +534,6 @@
 					(lb - strlen(" ") -
 					 (a + strlen("\nauthor "))));
 		email = xmemdupz(lb + strlen("<"), rb - (lb + strlen("<")));
-		date = xmemdupz(rb + strlen("> "), eol - (rb + strlen("> ")));
 		len = eol - (rb + strlen("> "));
 		date = xmalloc(len + 2);
 		*date = '@';
diff --git a/cache.h b/cache.h
index 4c606ce..3a69638 100644
--- a/cache.h
+++ b/cache.h
@@ -577,6 +577,7 @@
 extern int prefer_symlink_refs;
 extern int log_all_ref_updates;
 extern int warn_ambiguous_refs;
+extern int warn_on_object_refname_ambiguity;
 extern int shared_repository;
 extern const char *apply_default_whitespace;
 extern const char *apply_default_ignorewhitespace;
@@ -1131,6 +1132,7 @@
 
 struct object_info {
 	/* Request */
+	enum object_type *typep;
 	unsigned long *sizep;
 	unsigned long *disk_sizep;
 
diff --git a/compat/unsetenv.c b/compat/unsetenv.c
index 4ea1856..bf5fd70 100644
--- a/compat/unsetenv.c
+++ b/compat/unsetenv.c
@@ -2,6 +2,9 @@
 
 void gitunsetenv (const char *name)
 {
+#if !defined(__MINGW32__)
+     extern char **environ;
+#endif
      int src, dst;
      size_t nmln;
 
diff --git a/config.mak.uname b/config.mak.uname
index 7ac541e..b45b910 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -159,16 +159,17 @@
 		NO_SYMLINK_HEAD = YesPlease
 		NO_IPV6 = YesPlease
 		OLD_ICONV = UnfortunatelyYes
+		NO_THREAD_SAFE_PREAD = YesPlease
+		# There are conflicting reports about this.
+		# On some boxes NO_MMAP is needed, and not so elsewhere.
+		# Try commenting this out if you suspect MMAP is more efficient
+		NO_MMAP = YesPlease
+	else
+		NO_REGEX = UnfortunatelyYes
 	endif
-	NO_THREAD_SAFE_PREAD = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	NO_FAST_WORKING_DIRECTORY = UnfortunatelyYes
-	NO_TRUSTABLE_FILEMODE = UnfortunatelyYes
 	NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease
-	# There are conflicting reports about this.
-	# On some boxes NO_MMAP is needed, and not so elsewhere.
-	# Try commenting this out if you suspect MMAP is more efficient
-	NO_MMAP = YesPlease
 	X = .exe
 	COMPAT_OBJS += compat/cygwin.o
 	UNRELIABLE_FSTAT = UnfortunatelyYes
diff --git a/contrib/contacts/git-contacts b/contrib/contacts/git-contacts
new file mode 100755
index 0000000..d80f7d1
--- /dev/null
+++ b/contrib/contacts/git-contacts
@@ -0,0 +1,188 @@
+#!/usr/bin/perl
+
+# List people who might be interested in a patch.  Useful as the argument to
+# git-send-email --cc-cmd option, and in other situations.
+#
+# Usage: git contacts <file | rev-list option> ...
+
+use strict;
+use warnings;
+use IPC::Open2;
+
+my $since = '5-years-ago';
+my $min_percent = 10;
+my $labels_rx = qr/Signed-off-by|Reviewed-by|Acked-by|Cc/i;
+my %seen;
+
+sub format_contact {
+	my ($name, $email) = @_;
+	return "$name <$email>";
+}
+
+sub parse_commit {
+	my ($commit, $data) = @_;
+	my $contacts = $commit->{contacts};
+	my $inbody = 0;
+	for (split(/^/m, $data)) {
+		if (not $inbody) {
+			if (/^author ([^<>]+) <(\S+)> .+$/) {
+				$contacts->{format_contact($1, $2)} = 1;
+			} elsif (/^$/) {
+				$inbody = 1;
+			}
+		} elsif (/^$labels_rx:\s+([^<>]+)\s+<(\S+?)>$/o) {
+			$contacts->{format_contact($1, $2)} = 1;
+		}
+	}
+}
+
+sub import_commits {
+	my ($commits) = @_;
+	return unless %$commits;
+	my $pid = open2 my $reader, my $writer, qw(git cat-file --batch);
+	for my $id (keys(%$commits)) {
+		print $writer "$id\n";
+		my $line = <$reader>;
+		if ($line =~ /^([0-9a-f]{40}) commit (\d+)/) {
+			my ($cid, $len) = ($1, $2);
+			die "expected $id but got $cid\n" unless $id eq $cid;
+			my $data;
+			# cat-file emits newline after data, so read len+1
+			read $reader, $data, $len + 1;
+			parse_commit($commits->{$id}, $data);
+		}
+	}
+	close $reader;
+	close $writer;
+	waitpid($pid, 0);
+	die "git-cat-file error: $?\n" if $?;
+}
+
+sub get_blame {
+	my ($commits, $source, $start, $len, $from) = @_;
+	$len = 1 unless defined($len);
+	return if $len == 0;
+	open my $f, '-|',
+		qw(git blame --porcelain -C), '-L', "$start,+$len",
+		'--since', $since, "$from^", '--', $source or die;
+	while (<$f>) {
+		if (/^([0-9a-f]{40}) \d+ \d+ \d+$/) {
+			my $id = $1;
+			$commits->{$id} = { id => $id, contacts => {} }
+				unless $seen{$id};
+			$seen{$id} = 1;
+		}
+	}
+	close $f;
+}
+
+sub scan_patches {
+	my ($commits, $id, $f) = @_;
+	my $source;
+	while (<$f>) {
+		if (/^From ([0-9a-f]{40}) Mon Sep 17 00:00:00 2001$/) {
+			$id = $1;
+			$seen{$id} = 1;
+		}
+		next unless $id;
+		if (m{^--- (?:a/(.+)|/dev/null)$}) {
+			$source = $1;
+		} elsif (/^--- /) {
+			die "Cannot parse hunk source: $_\n";
+		} elsif (/^@@ -(\d+)(?:,(\d+))?/ && $source) {
+			get_blame($commits, $source, $1, $2, $id);
+		}
+	}
+}
+
+sub scan_patch_file {
+	my ($commits, $file) = @_;
+	open my $f, '<', $file or die "read failure: $file: $!\n";
+	scan_patches($commits, undef, $f);
+	close $f;
+}
+
+sub parse_rev_args {
+	my @args = @_;
+	open my $f, '-|',
+		qw(git rev-parse --revs-only --default HEAD --symbolic), @args
+		or die;
+	my @revs;
+	while (<$f>) {
+		chomp;
+		push @revs, $_;
+	}
+	close $f;
+	return @revs if scalar(@revs) != 1;
+	return "^$revs[0]", 'HEAD' unless $revs[0] =~ /^-/;
+	return $revs[0], 'HEAD';
+}
+
+sub scan_rev_args {
+	my ($commits, $args) = @_;
+	my @revs = parse_rev_args(@$args);
+	open my $f, '-|', qw(git rev-list --reverse), @revs or die;
+	while (<$f>) {
+		chomp;
+		my $id = $_;
+		$seen{$id} = 1;
+		open my $g, '-|', qw(git show -C --oneline), $id or die;
+		scan_patches($commits, $id, $g);
+		close $g;
+	}
+	close $f;
+}
+
+sub mailmap_contacts {
+	my ($contacts) = @_;
+	my %mapped;
+	my $pid = open2 my $reader, my $writer, qw(git check-mailmap --stdin);
+	for my $contact (keys(%$contacts)) {
+		print $writer "$contact\n";
+		my $canonical = <$reader>;
+		chomp $canonical;
+		$mapped{$canonical} += $contacts->{$contact};
+	}
+	close $reader;
+	close $writer;
+	waitpid($pid, 0);
+	die "git-check-mailmap error: $?\n" if $?;
+	return \%mapped;
+}
+
+if (!@ARGV) {
+	die "No input revisions or patch files\n";
+}
+
+my (@files, @rev_args);
+for (@ARGV) {
+	if (-e) {
+		push @files, $_;
+	} else {
+		push @rev_args, $_;
+	}
+}
+
+my %commits;
+for (@files) {
+	scan_patch_file(\%commits, $_);
+}
+if (@rev_args) {
+	scan_rev_args(\%commits, \@rev_args)
+}
+import_commits(\%commits);
+
+my $contacts = {};
+for my $commit (values %commits) {
+	for my $contact (keys %{$commit->{contacts}}) {
+		$contacts->{$contact}++;
+	}
+}
+$contacts = mailmap_contacts($contacts);
+
+my $ncommits = scalar(keys %commits);
+for my $contact (keys %$contacts) {
+	my $percent = $contacts->{$contact} * 100 / $ncommits;
+	next if $percent < $min_percent;
+	print "$contact\n";
+}
diff --git a/contrib/contacts/git-contacts.txt b/contrib/contacts/git-contacts.txt
new file mode 100644
index 0000000..dd914d1
--- /dev/null
+++ b/contrib/contacts/git-contacts.txt
@@ -0,0 +1,94 @@
+git-contacts(1)
+===============
+
+NAME
+----
+git-contacts - List people who might be interested in a set of changes
+
+
+SYNOPSIS
+--------
+[verse]
+'git contacts' (<patch>|<range>|<rev>)...
+
+
+DESCRIPTION
+-----------
+
+Given a set of changes, specified as patch files or revisions, determine people
+who might be interested in those changes.  This is done by consulting the
+history of each patch or revision hunk to find people mentioned by commits
+which touched the lines of files under consideration.
+
+Input consists of one or more patch files or revision arguments.  A revision
+argument can be a range or a single `<rev>` which is interpreted as
+`<rev>..HEAD`, thus the same revision arguments are accepted as for
+linkgit:git-format-patch[1]. Patch files and revision arguments can be combined
+in the same invocation.
+
+This command can be useful for determining the list of people with whom to
+discuss proposed changes, or for finding the list of recipients to Cc: when
+submitting a patch series via `git send-email`. For the latter case, `git
+contacts` can be used as the argument to `git send-email`'s `--cc-cmd` option.
+
+
+DISCUSSION
+----------
+
+`git blame` is invoked for each hunk in a patch file or revision.  For each
+commit mentioned by `git blame`, the commit message is consulted for people who
+authored, reviewed, signed, acknowledged, or were Cc:'d.  Once the list of
+participants is known, each person's relevance is computed by considering how
+many commits mentioned that person compared with the total number of commits
+under consideration.  The final output consists only of participants who exceed
+a minimum threshold of participation.
+
+
+OUTPUT
+------
+
+For each person of interest, a single line is output, terminated by a newline.
+If the person's name is known, ``Name $$<user@host>$$'' is printed; otherwise
+only ``$$<user@host>$$'' is printed.
+
+
+EXAMPLES
+--------
+
+* Consult patch files:
++
+------------
+$ git contacts feature/*.patch
+------------
+
+* Revision range:
++
+------------
+$ git contacts R1..R2
+------------
+
+* From a single revision to `HEAD`:
++
+------------
+$ git contacts origin
+------------
+
+* Helper for `git send-email`:
++
+------------
+$ git send-email --cc-cmd='git contacts' feature/*.patch
+------------
+
+
+LIMITATIONS
+-----------
+
+Several conditions controlling a person's significance are currently
+hard-coded, such as minimum participation level (10%), blame date-limiting (5
+years), and `-C` level for detecting moved and copied lines (a single `-C`). In
+the future, these conditions may become configurable.
+
+
+GIT
+---
+Part of the linkgit:git[1] suite
diff --git a/daemon.c b/daemon.c
index 973ec38..34916c5 100644
--- a/daemon.c
+++ b/daemon.c
@@ -760,7 +760,7 @@
 		snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d",
 		    ntohs(sin_addr->sin_port));
 #ifndef NO_IPV6
-	} else if (addr && addr->sa_family == AF_INET6) {
+	} else if (addr->sa_family == AF_INET6) {
 		struct sockaddr_in6 *sin6_addr = (void *) addr;
 
 		char *buf = addrbuf + 12;
diff --git a/diff.c b/diff.c
index 76c6d8d..266112c 100644
--- a/diff.c
+++ b/diff.c
@@ -1683,9 +1683,7 @@
 		del = deleted;
 
 		if (graph_width <= max_change) {
-			int total = add + del;
-
-			total = scale_linear(add + del, graph_width, max_change);
+			int total = scale_linear(add + del, graph_width, max_change);
 			if (total < 2 && add && del)
 				/* width >= 2 due to the sanity check */
 				total = 2;
diff --git a/environment.c b/environment.c
index 0cb67b2..5398c36 100644
--- a/environment.c
+++ b/environment.c
@@ -22,6 +22,7 @@
 int is_bare_repository_cfg = -1; /* unspecified */
 int log_all_ref_updates = -1; /* unspecified */
 int warn_ambiguous_refs = 1;
+int warn_on_object_refname_ambiguity = 1;
 int repository_format_version;
 const char *git_commit_encoding;
 const char *git_log_output_encoding;
diff --git a/line-log.c b/line-log.c
index 8cc29a0..c2d01dc 100644
--- a/line-log.c
+++ b/line-log.c
@@ -110,12 +110,14 @@
 static void sort_and_merge_range_set(struct range_set *rs)
 {
 	int i;
-	int o = 1; /* output cursor */
+	int o = 0; /* output cursor */
 
 	qsort(rs->ranges, rs->nr, sizeof(struct range), range_cmp);
 
-	for (i = 1; i < rs->nr; i++) {
-		if (rs->ranges[i].start <= rs->ranges[o-1].end) {
+	for (i = 0; i < rs->nr; i++) {
+		if (rs->ranges[i].start == rs->ranges[i].end)
+			continue;
+		if (o > 0 && rs->ranges[i].start <= rs->ranges[o-1].end) {
 			if (rs->ranges[o-1].end < rs->ranges[i].end)
 				rs->ranges[o-1].end = rs->ranges[i].end;
 		} else {
@@ -297,6 +299,7 @@
 	p = xcalloc(1, sizeof(struct line_log_data));
 	p->path = path;
 	range_set_append(&p->ranges, begin, end);
+	sort_and_merge_range_set(&p->ranges);
 	if (ip) {
 		p->next = ip->next;
 		ip->next = p;
diff --git a/refs.c b/refs.c
index 4302206..a3f2302 100644
--- a/refs.c
+++ b/refs.c
@@ -2174,11 +2174,14 @@
 {
 	struct packed_ref_cache *packed_ref_cache;
 
-	/* Discard the old cache because it might be invalid: */
-	clear_packed_ref_cache(&ref_cache);
 	if (hold_lock_file_for_update(&packlock, git_path("packed-refs"), flags) < 0)
 		return -1;
-	/* Read the current packed-refs while holding the lock: */
+	/*
+	 * Get the current packed-refs while holding the lock.  If the
+	 * packed-refs file has been modified since we last read it,
+	 * this will automatically invalidate the cache and re-read
+	 * the packed-refs file.
+	 */
 	packed_ref_cache = get_packed_ref_cache(&ref_cache);
 	packed_ref_cache->lock = &packlock;
 	/* Increment the reference count to prevent it from being freed: */
diff --git a/sha1_file.c b/sha1_file.c
index 4c2365f..8e27db1 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1306,6 +1306,26 @@
 	}
 }
 
+static int stat_sha1_file(const unsigned char *sha1, struct stat *st)
+{
+	char *name = sha1_file_name(sha1);
+	struct alternate_object_database *alt;
+
+	if (!lstat(name, st))
+		return 0;
+
+	prepare_alt_odb();
+	errno = ENOENT;
+	for (alt = alt_odb_list; alt; alt = alt->next) {
+		name = alt->name;
+		fill_sha1_path(name, sha1);
+		if (!lstat(alt->base, st))
+			return 0;
+	}
+
+	return -1;
+}
+
 static int open_sha1_file(const unsigned char *sha1)
 {
 	int fd;
@@ -1693,52 +1713,21 @@
 	return type;
 }
 
-
 #define POI_STACK_PREALLOC 64
 
-static int packed_object_info(struct packed_git *p, off_t obj_offset,
-			      unsigned long *sizep, int *rtype,
-			      unsigned long *disk_sizep)
+static enum object_type packed_to_object_type(struct packed_git *p,
+					      off_t obj_offset,
+					      enum object_type type,
+					      struct pack_window **w_curs,
+					      off_t curpos)
 {
-	struct pack_window *w_curs = NULL;
-	unsigned long size;
-	off_t curpos = obj_offset;
-	enum object_type type;
 	off_t small_poi_stack[POI_STACK_PREALLOC];
 	off_t *poi_stack = small_poi_stack;
 	int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC;
 
-	type = unpack_object_header(p, &w_curs, &curpos, &size);
-
-	if (rtype)
-		*rtype = type; /* representation type */
-
-	if (sizep) {
-		if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
-			off_t tmp_pos = curpos;
-			off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
-							   type, obj_offset);
-			if (!base_offset) {
-				type = OBJ_BAD;
-				goto out;
-			}
-			*sizep = get_size_from_delta(p, &w_curs, tmp_pos);
-			if (*sizep == 0) {
-				type = OBJ_BAD;
-				goto out;
-			}
-		} else {
-			*sizep = size;
-		}
-	}
-
-	if (disk_sizep) {
-		struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
-		*disk_sizep = revidx[1].offset - obj_offset;
-	}
-
 	while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
 		off_t base_offset;
+		unsigned long size;
 		/* Push the object we're going to leave behind */
 		if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) {
 			poi_stack_alloc = alloc_nr(poi_stack_nr);
@@ -1749,11 +1738,11 @@
 		}
 		poi_stack[poi_stack_nr++] = obj_offset;
 		/* If parsing the base offset fails, just unwind */
-		base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
+		base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
 		if (!base_offset)
 			goto unwind;
 		curpos = obj_offset = base_offset;
-		type = unpack_object_header(p, &w_curs, &curpos, &size);
+		type = unpack_object_header(p, w_curs, &curpos, &size);
 		if (type <= OBJ_NONE) {
 			/* If getting the base itself fails, we first
 			 * retry the base, otherwise unwind */
@@ -1780,7 +1769,6 @@
 out:
 	if (poi_stack != small_poi_stack)
 		free(poi_stack);
-	unuse_pack(&w_curs);
 	return type;
 
 unwind:
@@ -1794,6 +1782,57 @@
 	goto out;
 }
 
+static int packed_object_info(struct packed_git *p, off_t obj_offset,
+			      struct object_info *oi)
+{
+	struct pack_window *w_curs = NULL;
+	unsigned long size;
+	off_t curpos = obj_offset;
+	enum object_type type;
+
+	/*
+	 * We always get the representation type, but only convert it to
+	 * a "real" type later if the caller is interested.
+	 */
+	type = unpack_object_header(p, &w_curs, &curpos, &size);
+
+	if (oi->sizep) {
+		if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
+			off_t tmp_pos = curpos;
+			off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
+							   type, obj_offset);
+			if (!base_offset) {
+				type = OBJ_BAD;
+				goto out;
+			}
+			*oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos);
+			if (*oi->sizep == 0) {
+				type = OBJ_BAD;
+				goto out;
+			}
+		} else {
+			*oi->sizep = size;
+		}
+	}
+
+	if (oi->disk_sizep) {
+		struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
+		*oi->disk_sizep = revidx[1].offset - obj_offset;
+	}
+
+	if (oi->typep) {
+		*oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
+		if (*oi->typep < 0) {
+			type = OBJ_BAD;
+			goto out;
+		}
+	}
+
+out:
+	unuse_pack(&w_curs);
+	return type;
+}
+
 static void *unpack_compressed_entry(struct packed_git *p,
 				    struct pack_window **w_curs,
 				    off_t curpos,
@@ -2363,8 +2402,8 @@
 
 }
 
-static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep,
-				  unsigned long *disk_sizep)
+static int sha1_loose_object_info(const unsigned char *sha1,
+				  struct object_info *oi)
 {
 	int status;
 	unsigned long mapsize, size;
@@ -2372,21 +2411,37 @@
 	git_zstream stream;
 	char hdr[32];
 
+	/*
+	 * If we don't care about type or size, then we don't
+	 * need to look inside the object at all.
+	 */
+	if (!oi->typep && !oi->sizep) {
+		if (oi->disk_sizep) {
+			struct stat st;
+			if (stat_sha1_file(sha1, &st) < 0)
+				return -1;
+			*oi->disk_sizep = st.st_size;
+		}
+		return 0;
+	}
+
 	map = map_sha1_file(sha1, &mapsize);
 	if (!map)
 		return -1;
-	if (disk_sizep)
-		*disk_sizep = mapsize;
+	if (oi->disk_sizep)
+		*oi->disk_sizep = mapsize;
 	if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
 		status = error("unable to unpack %s header",
 			       sha1_to_hex(sha1));
 	else if ((status = parse_sha1_header(hdr, &size)) < 0)
 		status = error("unable to parse %s header", sha1_to_hex(sha1));
-	else if (sizep)
-		*sizep = size;
+	else if (oi->sizep)
+		*oi->sizep = size;
 	git_inflate_end(&stream);
 	munmap(map, mapsize);
-	return status;
+	if (oi->typep)
+		*oi->typep = status;
+	return 0;
 }
 
 /* returns enum object_type or negative */
@@ -2394,37 +2449,37 @@
 {
 	struct cached_object *co;
 	struct pack_entry e;
-	int status, rtype;
+	int rtype;
 
 	co = find_cached_object(sha1);
 	if (co) {
+		if (oi->typep)
+			*(oi->typep) = co->type;
 		if (oi->sizep)
 			*(oi->sizep) = co->size;
 		if (oi->disk_sizep)
 			*(oi->disk_sizep) = 0;
 		oi->whence = OI_CACHED;
-		return co->type;
+		return 0;
 	}
 
 	if (!find_pack_entry(sha1, &e)) {
 		/* Most likely it's a loose object. */
-		status = sha1_loose_object_info(sha1, oi->sizep, oi->disk_sizep);
-		if (status >= 0) {
+		if (!sha1_loose_object_info(sha1, oi)) {
 			oi->whence = OI_LOOSE;
-			return status;
+			return 0;
 		}
 
 		/* Not a loose object; someone else may have just packed it. */
 		reprepare_packed_git();
 		if (!find_pack_entry(sha1, &e))
-			return status;
+			return -1;
 	}
 
-	status = packed_object_info(e.p, e.offset, oi->sizep, &rtype,
-				    oi->disk_sizep);
-	if (status < 0) {
+	rtype = packed_object_info(e.p, e.offset, oi);
+	if (rtype < 0) {
 		mark_bad_packed_object(e.p, sha1);
-		status = sha1_object_info_extended(sha1, oi);
+		return sha1_object_info_extended(sha1, oi);
 	} else if (in_delta_base_cache(e.p, e.offset)) {
 		oi->whence = OI_DBCACHED;
 	} else {
@@ -2435,15 +2490,19 @@
 					 rtype == OBJ_OFS_DELTA);
 	}
 
-	return status;
+	return 0;
 }
 
 int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
 {
-	struct object_info oi = {0};
+	enum object_type type;
+	struct object_info oi = {NULL};
 
+	oi.typep = &type;
 	oi.sizep = sizep;
-	return sha1_object_info_extended(sha1, &oi);
+	if (sha1_object_info_extended(sha1, &oi) < 0)
+		return -1;
+	return type;
 }
 
 static void *read_packed_sha1(const unsigned char *sha1,
diff --git a/sha1_name.c b/sha1_name.c
index 6f7d4d1..1d210e3 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -452,13 +452,15 @@
 	int at, reflog_len, nth_prior = 0;
 
 	if (len == 40 && !get_sha1_hex(str, sha1)) {
-		refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
-		if (refs_found > 0 && warn_ambiguous_refs) {
-			warning(warn_msg, len, str);
-			if (advice_object_name_warning)
-				fprintf(stderr, "%s\n", _(object_name_msg));
+		if (warn_on_object_refname_ambiguity) {
+			refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
+			if (refs_found > 0 && warn_ambiguous_refs) {
+				warning(warn_msg, len, str);
+				if (advice_object_name_warning)
+					fprintf(stderr, "%s\n", _(object_name_msg));
+			}
+			free(real_ref);
 		}
-		free(real_ref);
 		return 0;
 	}
 
diff --git a/streaming.c b/streaming.c
index cac282f..debe904 100644
--- a/streaming.c
+++ b/streaming.c
@@ -111,11 +111,11 @@
 	unsigned long size;
 	int status;
 
+	oi->typep = type;
 	oi->sizep = &size;
 	status = sha1_object_info_extended(sha1, oi);
 	if (status < 0)
 		return stream_error;
-	*type = status;
 
 	switch (oi->whence) {
 	case OI_LOOSE:
@@ -135,7 +135,7 @@
 				 struct stream_filter *filter)
 {
 	struct git_istream *st;
-	struct object_info oi = {0};
+	struct object_info oi = {NULL};
 	const unsigned char *real = lookup_replace_object(sha1);
 	enum input_source src = istream_source(real, type, &oi);
 
@@ -149,7 +149,7 @@
 			return NULL;
 		}
 	}
-	if (st && filter) {
+	if (filter) {
 		/* Add "&& !is_null_stream_filter(filter)" for performance */
 		struct git_istream *nst = attach_stream_filter(st, filter);
 		if (!nst)
diff --git a/t/t3032-merge-recursive-options.sh b/t/t3032-merge-recursive-options.sh
index 2b17311..5fd7bbb 100755
--- a/t/t3032-merge-recursive-options.sh
+++ b/t/t3032-merge-recursive-options.sh
@@ -14,7 +14,7 @@
 . ./test-lib.sh
 
 test_have_prereq SED_STRIPS_CR && SED_OPTIONS=-b
-test_have_prereq MINGW && export GREP_OPTIONS=-U
+test_have_prereq GREP_STRIPS_CR && export GREP_OPTIONS=-U
 
 test_expect_success 'setup' '
 	conflict_hunks () {
diff --git a/t/t4211-line-log.sh b/t/t4211-line-log.sh
index 7776f93..7665d67 100755
--- a/t/t4211-line-log.sh
+++ b/t/t4211-line-log.sh
@@ -64,4 +64,17 @@
 test_bad_opts "-L :b.c" "argument.*not of the form"
 test_bad_opts "-L :foo:b.c" "no match"
 
+# There is a separate bug when an empty -L range is the first -L encountered,
+# thus to demonstrate this particular bug, the empty -L range must follow a
+# non-empty -L range.
+test_expect_success '-L {empty-range} (any -L)' '
+	n=$(expr $(wc -l <b.c) + 1) &&
+	git log -L1,1:b.c -L$n:b.c
+'
+
+test_expect_success '-L {empty-range} (first -L)' '
+	n=$(expr $(wc -l <b.c) + 1) &&
+	git log -L$n:b.c
+'
+
 test_done
diff --git a/t/t5560-http-backend-noserver.sh b/t/t5560-http-backend-noserver.sh
index ef98d95..9be9ae3 100755
--- a/t/t5560-http-backend-noserver.sh
+++ b/t/t5560-http-backend-noserver.sh
@@ -5,7 +5,7 @@
 
 HTTPD_DOCUMENT_ROOT_PATH="$TRASH_DIRECTORY"
 
-test_have_prereq MINGW && export GREP_OPTIONS=-U
+test_have_prereq GREP_STRIPS_CR && export GREP_OPTIONS=-U
 
 run_backend() {
 	echo "$2" |
diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh
index 3ff5fb8..10aa028 100755
--- a/t/t7600-merge.sh
+++ b/t/t7600-merge.sh
@@ -502,7 +502,7 @@
 	test_must_fail git merge --no-ff --ff-only c2
 '
 
-test_expect_success 'option --ff-only overwrites merge.ff=only config' '
+test_expect_success 'option --no-ff overrides merge.ff=only config' '
 	git reset --hard c0 &&
 	test_config merge.ff only &&
 	git merge --no-ff c1
diff --git a/t/test-lib.sh b/t/test-lib.sh
index b4902831..1aa27bd 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -825,6 +825,7 @@
 	test_set_prereq MINGW
 	test_set_prereq NOT_CYGWIN
 	test_set_prereq SED_STRIPS_CR
+	test_set_prereq GREP_STRIPS_CR
 	;;
 *CYGWIN*)
 	test_set_prereq POSIXPERM
@@ -832,6 +833,7 @@
 	test_set_prereq NOT_MINGW
 	test_set_prereq CYGWIN
 	test_set_prereq SED_STRIPS_CR
+	test_set_prereq GREP_STRIPS_CR
 	;;
 *)
 	test_set_prereq POSIXPERM
diff --git a/templates/hooks--pre-commit.sample b/templates/hooks--pre-commit.sample
index 18c4829..586e3bf 100755
--- a/templates/hooks--pre-commit.sample
+++ b/templates/hooks--pre-commit.sample
@@ -15,13 +15,13 @@
 	against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
 fi
 
-# If you want to allow non-ascii filenames set this variable to true.
+# If you want to allow non-ASCII filenames set this variable to true.
 allownonascii=$(git config hooks.allownonascii)
 
 # Redirect output to stderr.
 exec 1>&2
 
-# Cross platform projects tend to avoid non-ascii filenames; prevent
+# Cross platform projects tend to avoid non-ASCII filenames; prevent
 # them from being added to the repository. We exploit the fact that the
 # printable range starts at the space character and ends with tilde.
 if [ "$allownonascii" != "true" ] &&
@@ -31,18 +31,17 @@
 	test $(git diff --cached --name-only --diff-filter=A -z $against |
 	  LC_ALL=C tr -d '[ -~]\0' | wc -c) != 0
 then
-	echo "Error: Attempt to add a non-ascii file name."
-	echo
-	echo "This can cause problems if you want to work"
-	echo "with people on other platforms."
-	echo
-	echo "To be portable it is advisable to rename the file ..."
-	echo
-	echo "If you know what you are doing you can disable this"
-	echo "check using:"
-	echo
-	echo "  git config hooks.allownonascii true"
-	echo
+	cat <<\EOF
+Error: Attempt to add a non-ASCII file name.
+
+This can cause problems if you want to work with people on other platforms.
+
+To be portable it is advisable to rename the file.
+
+If you know what you are doing you can disable this check using:
+
+  git config hooks.allownonascii true
+EOF
 	exit 1
 fi
 
diff --git a/tree-walk.c b/tree-walk.c
index 6e30ef9..c626135 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -323,7 +323,6 @@
 
 int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
 {
-	int ret = 0;
 	int error = 0;
 	struct name_entry *entry = xmalloc(n*sizeof(*entry));
 	int i;
@@ -341,6 +340,7 @@
 		strbuf_setlen(&base, info->pathlen);
 	}
 	for (;;) {
+		int trees_used;
 		unsigned long mask, dirmask;
 		const char *first = NULL;
 		int first_len = 0;
@@ -404,15 +404,14 @@
 		if (interesting < 0)
 			break;
 		if (interesting) {
-			ret = info->fn(n, mask, dirmask, entry, info);
-			if (ret < 0) {
-				error = ret;
+			trees_used = info->fn(n, mask, dirmask, entry, info);
+			if (trees_used < 0) {
+				error = trees_used;
 				if (!info->show_all_errors)
 					break;
 			}
-			mask &= ret;
+			mask &= trees_used;
 		}
-		ret = 0;
 		for (i = 0; i < n; i++)
 			if (mask & (1ul << i))
 				update_extended_entry(tx + i, entry + i);