diff --git a/builtin/fsck.c b/builtin/fsck.c
index 055dfdcf9e..f01b81eebf 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -644,14 +644,8 @@ int cmd_fsck(int argc, const char **argv, const char *prefix)
 		fsck_object_dir(get_object_directory());
 
 		prepare_alt_odb();
-		for (alt = alt_odb_list; alt; alt = alt->next) {
-			/* directory name, minus trailing slash */
-			size_t namelen = alt->name - alt->base - 1;
-			struct strbuf name = STRBUF_INIT;
-			strbuf_add(&name, alt->base, namelen);
-			fsck_object_dir(name.buf);
-			strbuf_release(&name);
-		}
+		for (alt = alt_odb_list; alt; alt = alt->next)
+			fsck_object_dir(alt->path);
 	}
 
 	if (check_full) {
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index e3fdc0aa78..fd72c90442 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -492,20 +492,16 @@ static int add_possible_reference_from_superproject(
 {
 	struct submodule_alternate_setup *sas = sas_cb;
 
-	/* directory name, minus trailing slash */
-	size_t namelen = alt->name - alt->base - 1;
-	struct strbuf name = STRBUF_INIT;
-	strbuf_add(&name, alt->base, namelen);
-
 	/*
 	 * If the alternate object store is another repository, try the
 	 * standard layout with .git/modules/<name>/objects
 	 */
-	if (ends_with(name.buf, ".git/objects")) {
+	if (ends_with(alt->path, ".git/objects")) {
 		char *sm_alternate;
 		struct strbuf sb = STRBUF_INIT;
 		struct strbuf err = STRBUF_INIT;
-		strbuf_add(&sb, name.buf, name.len - strlen("objects"));
+		strbuf_add(&sb, alt->path, strlen(alt->path) - strlen("objects"));
+
 		/*
 		 * We need to end the new path with '/' to mark it as a dir,
 		 * otherwise a submodule name containing '/' will be broken
@@ -533,7 +529,6 @@ static int add_possible_reference_from_superproject(
 		strbuf_release(&sb);
 	}
 
-	strbuf_release(&name);
 	return 0;
 }
 
diff --git a/cache.h b/cache.h
index ece2c7c9b8..555ba713de 100644
--- a/cache.h
+++ b/cache.h
@@ -1383,8 +1383,11 @@ extern void remove_scheduled_dirs(void);
 
 extern struct alternate_object_database {
 	struct alternate_object_database *next;
+
 	char *name;
-	char base[FLEX_ARRAY]; /* more */
+	char *scratch;
+
+	char path[FLEX_ARRAY];
 } *alt_odb_list;
 extern void prepare_alt_odb(void);
 extern void read_info_alternates(const char * relative_base, int depth);
diff --git a/sha1_file.c b/sha1_file.c
index b284cea8fb..011532a709 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -208,7 +208,7 @@ static const char *alt_sha1_path(struct alternate_object_database *alt,
 				 const unsigned char *sha1)
 {
 	fill_sha1_path(alt->name, sha1);
-	return alt->base;
+	return alt->scratch;
 }
 
 /*
@@ -261,8 +261,7 @@ static int alt_odb_usable(struct strbuf *path, const char *normalized_objdir)
 	 * thing twice, or object directory itself.
 	 */
 	for (alt = alt_odb_list; alt; alt = alt->next) {
-		if (path->len == alt->name - alt->base - 1 &&
-		    !memcmp(path->buf, alt->base, path->len))
+		if (!strcmp(path->buf, alt->path))
 			return 0;
 	}
 	if (!fspathcmp(path->buf, normalized_objdir))
@@ -401,13 +400,14 @@ struct alternate_object_database *alloc_alt_odb(const char *dir)
 	size_t entlen;
 
 	entlen = st_add(dirlen, 43); /* '/' + 2 hex + '/' + 38 hex + NUL */
-	ent = xmalloc(st_add(sizeof(*ent), entlen));
-	memcpy(ent->base, dir, dirlen);
+	FLEX_ALLOC_STR(ent, path, dir);
+	ent->scratch = xmalloc(entlen);
+	xsnprintf(ent->scratch, entlen, "%s/", dir);
 
-	ent->name = ent->base + dirlen + 1;
-	ent->base[dirlen] = '/';
-	ent->base[dirlen + 3] = '/';
-	ent->base[entlen-1] = 0;
+	ent->name = ent->scratch + dirlen + 1;
+	ent->scratch[dirlen] = '/';
+	ent->scratch[dirlen + 3] = '/';
+	ent->scratch[entlen-1] = 0;
 
 	return ent;
 }
@@ -1485,11 +1485,8 @@ void prepare_packed_git(void)
 		return;
 	prepare_packed_git_one(get_object_directory(), 1);
 	prepare_alt_odb();
-	for (alt = alt_odb_list; alt; alt = alt->next) {
-		alt->name[-1] = 0;
-		prepare_packed_git_one(alt->base, 0);
-		alt->name[-1] = '/';
-	}
+	for (alt = alt_odb_list; alt; alt = alt->next)
+		prepare_packed_git_one(alt->path, 0);
 	rearrange_packed_git();
 	prepare_packed_git_mru();
 	prepare_packed_git_run_once = 1;
@@ -3692,8 +3689,7 @@ static int loose_from_alt_odb(struct alternate_object_database *alt,
 	struct strbuf buf = STRBUF_INIT;
 	int r;
 
-	/* copy base not including trailing '/' */
-	strbuf_add(&buf, alt->base, alt->name - alt->base - 1);
+	strbuf_addstr(&buf, alt->path);
 	r = for_each_loose_file_in_objdir_buf(&buf,
 					      data->cb, NULL, NULL,
 					      data->data);
diff --git a/sha1_name.c b/sha1_name.c
index 98152a68ba..770ea4fe80 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -94,12 +94,13 @@ static void find_short_object_filename(int len, const char *hex_pfx, struct disa
 	for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
 		struct dirent *de;
 		DIR *dir;
+
 		/*
 		 * every alt_odb struct has 42 extra bytes after the base
 		 * for exactly this purpose
 		 */
 		xsnprintf(alt->name, 42, "%.2s/", hex_pfx);
-		dir = opendir(alt->base);
+		dir = opendir(alt->scratch);
 		if (!dir)
 			continue;
 
diff --git a/transport.c b/transport.c
index 94d6dc3725..4bc4eeae54 100644
--- a/transport.c
+++ b/transport.c
@@ -1084,9 +1084,7 @@ static int refs_from_alternate_cb(struct alternate_object_database *e,
 	const struct ref *extra;
 	struct alternate_refs_data *cb = data;
 
-	e->name[-1] = '\0';
-	other = xstrdup(real_path(e->base));
-	e->name[-1] = '/';
+	other = xstrdup(real_path(e->path));
 	len = strlen(other);
 
 	while (other[len-1] == '/')