diff --git a/dir.c b/dir.c
index 6172b3438d..0ea235f3d6 100644
--- a/dir.c
+++ b/dir.c
@@ -2364,7 +2364,7 @@ void write_untracked_extension(struct strbuf *out, struct untracked_cache *untra
 
 	varint_len = encode_varint(untracked->ident.len, varbuf);
 	strbuf_add(out, varbuf, varint_len);
-	strbuf_add(out, untracked->ident.buf, untracked->ident.len);
+	strbuf_addbuf(out, &untracked->ident);
 
 	strbuf_add(out, ouc, ouc_size(len));
 	free(ouc);
diff --git a/path.c b/path.c
index 259aeed846..17551c4834 100644
--- a/path.c
+++ b/path.c
@@ -483,7 +483,7 @@ static void do_submodule_path(struct strbuf *buf, const char *path,
 		strbuf_addstr(buf, git_dir);
 	}
 	strbuf_addch(buf, '/');
-	strbuf_addstr(&git_submodule_dir, buf->buf);
+	strbuf_addbuf(&git_submodule_dir, buf);
 
 	strbuf_vaddf(buf, fmt, args);
 
diff --git a/strbuf.c b/strbuf.c
index 1ba600bd78..f3bd5719c6 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -197,6 +197,13 @@ void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 	strbuf_setlen(sb, sb->len + len);
 }
 
+void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
+{
+	strbuf_grow(sb, sb2->len);
+	memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
+	strbuf_setlen(sb, sb->len + sb2->len);
+}
+
 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 {
 	strbuf_grow(sb, len);
diff --git a/strbuf.h b/strbuf.h
index 83c5c98530..ba8d5f1d46 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -263,11 +263,7 @@ static inline void strbuf_addstr(struct strbuf *sb, const char *s)
 /**
  * Copy the contents of another buffer at the end of the current one.
  */
-static inline void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
-{
-	strbuf_grow(sb, sb2->len);
-	strbuf_add(sb, sb2->buf, sb2->len);
-}
+extern void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2);
 
 /**
  * Copy part of the buffer from a given position till a given length to the
diff --git a/wt-status.c b/wt-status.c
index 4ce4e35ac3..617a284304 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -1062,7 +1062,7 @@ static void abbrev_sha1_in_line(struct strbuf *line)
 			strbuf_addf(split[1], "%s ", abbrev);
 			strbuf_reset(line);
 			for (i = 0; split[i]; i++)
-				strbuf_addf(line, "%s", split[i]->buf);
+				strbuf_addbuf(line, split[i]);
 		}
 	}
 	strbuf_list_free(split);