diff --git a/fstrim.c b/fstrim.c
index 895d44f..8a02c77 100644
--- a/fstrim.c
+++ b/fstrim.c
@@ -16,6 +16,7 @@
 
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <sys/ioctl.h>