diff --git a/reactos/ntoskrnl/ke/i386/ctxswitch.S b/reactos/ntoskrnl/ke/i386/ctxswitch.S
index 3a35a3aa60d..7bd712eb634 100644
--- a/reactos/ntoskrnl/ke/i386/ctxswitch.S
+++ b/reactos/ntoskrnl/ke/i386/ctxswitch.S
@@ -18,6 +18,7 @@ EXTERN @KiSwapContextExit@8:PROC
 EXTERN @KiRetireDpcList@4:PROC
 EXTERN @KiEnterV86Mode@4:PROC
 EXTERN @KiExitV86Mode@4:PROC
+EXTERN _KeI386FxsrPresent:DWORD
 
 /* FUNCTIONS ****************************************************************/
 .code