diff --git a/compat/basename.c b/compat/basename.c
index 3ba9227f8f..96bd9533b4 100644
--- a/compat/basename.c
+++ b/compat/basename.c
@@ -29,20 +29,15 @@ char *gitbasename (char *path)
 
 char *gitdirname(char *path)
 {
-	char *p = path, *after_slash = NULL, c;
+	static struct strbuf buf = STRBUF_INIT;
+	char *p = path, *slash = NULL, c;
 	int dos_drive_prefix;
 
 	if (!p)
 		return ".";
 
-	if ((dos_drive_prefix = skip_dos_drive_prefix(&p)) && !*p) {
-		static struct strbuf buf = STRBUF_INIT;
-
-dot:
-		strbuf_reset(&buf);
-		strbuf_addf(&buf, "%.*s.", dos_drive_prefix, path);
-		return buf.buf;
-	}
+	if ((dos_drive_prefix = skip_dos_drive_prefix(&p)) && !*p)
+		goto dot;
 
 	/*
 	 * POSIX.1-2001 says dirname("/") should return "/", and dirname("//")
@@ -51,7 +46,7 @@ dot:
 	if (is_dir_sep(*p)) {
 		if (!p[1] || (is_dir_sep(p[1]) && !p[2]))
 			return path;
-		after_slash = ++p;
+		slash = ++p;
 	}
 	while ((c = *(p++)))
 		if (is_dir_sep(c)) {
@@ -61,11 +56,16 @@ dot:
 			while (is_dir_sep(*p))
 				p++;
 			if (*p)
-				after_slash = tentative;
+				slash = tentative;
 		}
 
-	if (!after_slash)
-		goto dot;
-	*after_slash = '\0';
-	return path;
+	if (slash) {
+		*slash = '\0';
+		return path;
+	}
+
+dot:
+	strbuf_reset(&buf);
+	strbuf_addf(&buf, "%.*s.", dos_drive_prefix, path);
+	return buf.buf;
 }