diff --git a/src/slic3r/GUI/SysInfoDialog.cpp b/src/slic3r/GUI/SysInfoDialog.cpp
index b727264b6..6f8eeedcc 100644
--- a/src/slic3r/GUI/SysInfoDialog.cpp
+++ b/src/slic3r/GUI/SysInfoDialog.cpp
@@ -15,6 +15,7 @@
 #include "MainFrame.hpp"
 #include "wxExtensions.hpp"
 #include "../libslic3r/BlacklistedLibraryCheck.hpp"
+#include "format.hpp"
 
 #ifdef _WIN32
 	// The standard Windows includes.