diff --git a/lib/glob.c b/lib/glob.c
index 69311568ad3d..7aca76c25bcb 100644
--- a/lib/glob.c
+++ b/lib/glob.c
@@ -47,7 +47,7 @@ bool __pure glob_match(char const *pat, char const *str)
 	 * (no exception for /), it can be easily proved that there's
 	 * never a need to backtrack multiple levels.
 	 */
-	char const *back_pat = NULL, *back_str;
+	char const *back_pat = NULL, *back_str = NULL;
 
 	/*
 	 * Loop over each token (character or class) in pat, matching