diff --git a/src/common/engine/i_interface.cpp b/src/common/engine/i_interface.cpp
index 5460d8dd3..ab054b076 100644
--- a/src/common/engine/i_interface.cpp
+++ b/src/common/engine/i_interface.cpp
@@ -2,6 +2,7 @@
 #include "st_start.h"
 #include "gamestate.h"
 #include "startupinfo.h"
+#include "c_cvars.h"
 
 static_assert(sizeof(void*) == 8, "32 builds are not supported");
 
@@ -18,3 +19,7 @@ gamestate_t 	gamestate = GS_STARTUP;
 bool ToggleFullscreen;
 
 FStartupInfo GameStartupInfo;
+
+CVAR(Bool, queryiwad, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
+CVAR(String, defaultiwad, "", CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
+
diff --git a/src/d_iwad.cpp b/src/d_iwad.cpp
index 69be94244..bd25c267b 100644
--- a/src/d_iwad.cpp
+++ b/src/d_iwad.cpp
@@ -49,8 +49,8 @@
 #include "findfile.h"
 #include "i_interface.h"
 
-CVAR (Bool, queryiwad, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG);
-CVAR (String, defaultiwad, "", CVAR_ARCHIVE|CVAR_GLOBALCONFIG);
+EXTERN_CVAR(Bool, queryiwad);
+EXTERN_CVAR(Bool, defaultiwad);
 
 //==========================================================================
 //