diff --git a/src/extension.cpp b/src/extension.cpp
index 3011160..1270232 100644
--- a/src/extension.cpp
+++ b/src/extension.cpp
@@ -39,13 +39,8 @@ IForward *g_pPassFwd = NULL;
 
 int gSetCollisionSolverHookId, gShouldCollideHookId;
 
-#if defined(__linux__) && defined(__i386__)
-CDetour* PassServerEntityFilterFuncDetour;
-__attribute__((regparm(2))) bool (*PassServerEntityFilterFunc_Actual)(const IHandleEntity*, const IHandleEntity*);
-__attribute__((regparm(2))) bool PassServerEntityFilterFunc(const IHandleEntity* pTouch, const IHandleEntity* pPass)
-#else
-DETOUR_DECL_STATIC2( PassServerEntityFilterFunc, bool, const IHandleEntity *, pTouch, const IHandleEntity *, pPass )
-#endif
+
+DETOUR_CUSTOM_STATIC2( PassServerEntityFilterFunc, bool, const IHandleEntity *, pTouch, const IHandleEntity *, pPass )
 {
 	if ( g_pPassFwd->GetFunctionCount() == 0 )
 		return DETOUR_STATIC_CALL( PassServerEntityFilterFunc )( pTouch, pPass );
diff --git a/src/extension.h b/src/extension.h
index ff8e568..ce3faf6 100644
--- a/src/extension.h
+++ b/src/extension.h
@@ -107,5 +107,21 @@ inline const CBaseEntity *UTIL_EntityFromEntityHandle( const IHandleEntity *pCon
 	return pUnk->GetBaseEntity();
 }
 
+#define DETOUR_DECL_STATIC2_REGPARM(name, ret, p1type, p1name, p2type, p2name) \
+ret (*name##_Actual)(p1type, p2type) __attribute__((regparm(2))) = NULL; \
+ret name(p1type p1name, p2type p2name) __attribute__((regparm(2)))
+
+#define DETOUR_DECL_STATIC2_FASTCALL(name, ret, p1type, p1name, p2type, p2name) \
+ret (__fastcall *name##_Actual)(p1type, p2type) = NULL; \
+ret __fastcall name(p1type p1name, p2type p2name)
+
+
+#if SOURCE_ENGINE == SE_TF2 && defined(PLATFORM_LINUX) && defined(__i386__)
+	#define DETOUR_CUSTOM_STATIC2 DETOUR_DECL_STATIC2_REGPARM
+#elif SOURCE_ENGINE == SE_CSGO && defined(PLATFORM_WINDOWS)
+	#define DETOUR_CUSTOM_STATIC2 DETOUR_DECL_STATIC2_FASTCALL
+#else
+	#define DETOUR_CUSTOM_STATIC2 DETOUR_DECL_STATIC2
+#endif
 
 #endif // _INCLUDE_COLLISIONHOOK_EXTENSION_H_