Set pointer size to 8 instead of 4

src/Windows12/CodeGen.hs

@@ -91,7 +91,7 @@ size FloatType = return 8
 size StrType = size (PtrType CharType)
 size BoolType = return 1
 size CharType = return 1
-size (PtrType _) = return 4
+size (PtrType _) = return 8
 size (ArrayType t) = size (PtrType t)
 size (StructType name) = do
   fields <- getStructFields name