Bug: https://bugs.gentoo.org/896214
--- a/gphotofs.c
+++ b/gphotofs.c
@@ -26,6 +26,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/time.h>
+#include <locale.h>
 
 /*
  * Static variables set by command line arguments.