diff --git a/src/g_shared/a_sharedglobal.h b/src/g_shared/a_sharedglobal.h
index b0accd3fb0..ad662d0370 100644
--- a/src/g_shared/a_sharedglobal.h
+++ b/src/g_shared/a_sharedglobal.h
@@ -18,7 +18,6 @@ bool P_MorphMonster (AActor *actor, const PClass *morphClass);
 bool P_UpdateMorphedMonster (AActor *actor);
 
 
-struct side_t;
 
 class DBaseDecal : public DThinker
 {
diff --git a/src/g_shared/r_interpolate.h b/src/r_interpolate.h
similarity index 100%
rename from src/g_shared/r_interpolate.h
rename to src/r_interpolate.h