diff --git a/libraries/AP_Logger/AP_Logger_File.cpp b/libraries/AP_Logger/AP_Logger_File.cpp
index a03f6c320f..1b829dc770 100644
--- a/libraries/AP_Logger/AP_Logger_File.cpp
+++ b/libraries/AP_Logger/AP_Logger_File.cpp
@@ -17,6 +17,7 @@
 
 #include <AP_Common/AP_Common.h>
 #include <AP_InternalError/AP_InternalError.h>
+#include <AP_RTC/AP_RTC.h>
 
 #if HAL_OS_POSIX_IO
 #include <unistd.h>