diff --git a/dll/win32/kernel32_vista/sync.c b/dll/win32/kernel32_vista/sync.c
index 17d394955da..1f13206445e 100644
--- a/dll/win32/kernel32_vista/sync.c
+++ b/dll/win32/kernel32_vista/sync.c
@@ -48,9 +48,6 @@ VOID
 NTAPI
 RtlReleaseSRWLockExclusive(IN OUT PRTL_SRWLOCK SRWLock);
 
-ULONG
-NTAPI
-RtlNtStatusToDosError(IN NTSTATUS Status);
 
 VOID
 WINAPI