diff --git a/fuse/guestmount.c b/fuse/guestmount.c
index 7c5e0af57b..379346f90e 100644
--- a/fuse/guestmount.c
+++ b/fuse/guestmount.c
@@ -28,6 +28,7 @@
 #include <unistd.h>
 #include <getopt.h>
 #include <signal.h>
+#include <locale.h>
 
 /* We're still using some of FUSE to handle command line options. */
 #include <fuse.h>