diff --git a/Modules/_ctypes/libffi/src/x86/ffi_darwin.c b/Modules/_ctypes/libffi/src/x86/ffi_darwin.c
index 71ac587..6726afa 100644
--- a/Modules/_ctypes/libffi/src/x86/ffi_darwin.c
+++ b/Modules/_ctypes/libffi/src/x86/ffi_darwin.c
@@ -146,7 +146,9 @@
     case FFI_TYPE_SINT64:
     case FFI_TYPE_FLOAT:
     case FFI_TYPE_DOUBLE:
+#if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
     case FFI_TYPE_LONGDOUBLE:
+#endif
       cif->flags = (unsigned) cif->rtype->type;
       break;