src/x86/win32.S: Define ffi_closure_FASTCALL in the MASM section, too
diff --git a/src/x86/win32.S b/src/x86/win32.S
index 699ea46..daf0e79 100644
--- a/src/x86/win32.S
+++ b/src/x86/win32.S
@@ -201,6 +201,15 @@ ffi_closure_THISCALL PROC NEAR
jmp ffi_closure_STDCALL
ffi_closure_THISCALL ENDP
+ffi_closure_FASTCALL PROC NEAR
+ ;; Insert the register argument on the stack as the first argument
+ xchg DWORD PTR [esp+4], edx
+ xchg DWORD PTR [esp], ecx
+ push edx
+ push ecx
+ jmp ffi_closure_STDCALL
+ffi_closure_FASTCALL ENDP
+
ffi_closure_SYSV PROC NEAR FORCEFRAME
;; the ffi_closure ctx is passed in eax by the trampoline.