f

nac3core: add bound check for list slice
nac3core: add location information to codegen context
2022-04-05 15:28:21 +08:00 · 2022-04-05 14:29:40 +08:00 · 2022-04-05 14:29:40 +08:00 · 2022-04-05 10:10:08 +08:00 · 2022-04-05 10:06:36 +08:00 · 2022-04-05 10:06:14 +08:00
49 changed files with 1597 additions and 371 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@ -249,9 +249,9 @@ dependencies = [

 [[package]]
 name = "getrandom"
-version = "0.2.5"
+version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d39cd93900197114fa1fcb7ae84ca742095eed9442088988ae74fa744e930e77"
+checksum = "9be70c98951c83b8d2f8f60d7065fa6d5146873094452a1008da8c2f1e4205ad"
 dependencies = [
 "cfg-if",
 "libc",
@ -278,9 +278,9 @@ dependencies = [

 [[package]]
 name = "indexmap"
-version = "1.8.0"
+version = "1.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "282a6247722caba404c065016bbfa522806e51714c34f5dfc3e4a3a46fcb4223"
+checksum = "0f647032dfaa1f8b6dc29bd3edb7bbef4861b8b8007ebb118d6db284fd59f6ee"
 dependencies = [
 "autocfg",
 "hashbrown",
@ -329,7 +329,7 @@ dependencies = [
 "libc",
 "llvm-sys",
 "once_cell",
- "parking_lot",
+ "parking_lot 0.11.2",
 "regex",
 ]

@ -457,10 +457,11 @@ dependencies = [

 [[package]]
 name = "lock_api"
-version = "0.4.6"
+version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "88943dd7ef4a2e5a4bfa2753aaab3013e34ce2533d1996fb18ef591e315e2b3b"
+checksum = "327fa5b6a6940e4699ec49a9beae1ea4845c6bab9314e4f84ac68742139d8c53"
 dependencies = [
+ "autocfg",
 "scopeguard",
 ]

@ -495,7 +496,7 @@ dependencies = [
 "inkwell",
 "nac3core",
 "nac3parser",
- "parking_lot",
+ "parking_lot 0.11.2",
 "pyo3",
 "tempfile",
 ]
@ -506,7 +507,7 @@ version = "0.1.0"
 dependencies = [
 "fxhash",
 "lazy_static",
- "parking_lot",
+ "parking_lot 0.11.2",
 "string-interner",
 ]

@ -520,7 +521,7 @@ dependencies = [
 "insta",
 "itertools",
 "nac3parser",
- "parking_lot",
+ "parking_lot 0.11.2",
 "rayon",
 "regex",
 "test-case",
@ -549,7 +550,7 @@ dependencies = [
 "inkwell",
 "nac3core",
 "nac3parser",
- "parking_lot",
+ "parking_lot 0.11.2",
 ]

 [[package]]
@ -582,7 +583,17 @@ checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
 dependencies = [
 "instant",
 "lock_api",
- "parking_lot_core",
+ "parking_lot_core 0.8.5",
+]
+
+[[package]]
+name = "parking_lot"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f5ec2493a61ac0506c0f4199f99070cbe83857b0337006a30f3e6719b8ef58"
+dependencies = [
+ "lock_api",
+ "parking_lot_core 0.9.2",
 ]

 [[package]]
@ -599,6 +610,19 @@ dependencies = [
 "winapi",
 ]

+[[package]]
+name = "parking_lot_core"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "995f667a6c822200b0433ac218e05582f0e2efa1b922a3fd2fbaadc5f87bab37"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "windows-sys",
+]
+
 [[package]]
 name = "paste"
 version = "0.1.18"
@ -732,7 +756,7 @@ dependencies = [
 "cfg-if",
 "indoc 0.3.6",
 "libc",
- "parking_lot",
+ "parking_lot 0.11.2",
 "paste",
 "pyo3-build-config",
 "pyo3-macros",
@ -773,9 +797,9 @@ dependencies = [

 [[package]]
 name = "quote"
-version = "1.0.16"
+version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b4af2ec4714533fcdf07e886f17025ace8b997b9ce51204ee69b6da831c3da57"
+checksum = "632d02bff7f874a36f33ea8bb416cd484b90cc66c1194b1a1110d067a7013f58"
 dependencies = [
 "proc-macro2",
 ]
@ -837,18 +861,18 @@ dependencies = [

 [[package]]
 name = "redox_syscall"
-version = "0.2.11"
+version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8380fe0152551244f0747b1bf41737e0f8a74f97a14ccefd1148187271634f3c"
+checksum = "62f25bc4c7e55e0b0b7a1d43fb893f4fa1361d0abe38b9ce4f323c2adfe6ef42"
 dependencies = [
 "bitflags",
 ]

 [[package]]
 name = "redox_users"
-version = "0.4.2"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7776223e2696f1aa4c6b0170e83212f47296a00424305117d013dfe86fb0fe55"
+checksum = "b033d837a7cf162d7993aded9304e30a83213c648b6e389db233191f891e5c2b"
 dependencies = [
 "getrandom",
 "redox_syscall",
@ -998,22 +1022,22 @@ dependencies = [

 [[package]]
 name = "string_cache"
-version = "0.8.3"
+version = "0.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "33994d0838dc2d152d17a62adf608a869b5e846b65b389af7f3dbc1de45c5b26"
+checksum = "213494b7a2b503146286049378ce02b482200519accc31872ee8be91fa820a08"
 dependencies = [
- "lazy_static",
 "new_debug_unreachable",
- "parking_lot",
+ "once_cell",
+ "parking_lot 0.12.0",
 "phf_shared 0.10.0",
 "precomputed-hash",
 ]

 [[package]]
 name = "syn"
-version = "1.0.89"
+version = "1.0.90"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea297be220d52398dcc07ce15a209fce436d361735ac1db700cab3b6cdfb9f54"
+checksum = "704df27628939572cd88d33f171cd6f896f4eaca85252c6e0a72d8d8287ee86f"
 dependencies = [
 "proc-macro2",
 "quote",
@ -1207,6 +1231,49 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

+[[package]]
+name = "windows-sys"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5acdd78cb4ba54c0045ac14f62d8f94a03d10047904ae2a40afa1e99d8f70825"
+dependencies = [
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "17cffbe740121affb56fad0fc0e421804adf0ae00891205213b5cecd30db881d"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2564fde759adb79129d9b4f54be42b32c89970c18ebf93124ca8870a498688ed"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9cd9d32ba70453522332c14d38814bceeb747d80b3958676007acadd7e166956"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfce6deae227ee8d356d19effc141a509cc503dfd1f850622ec4b0f84428e1f4"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.34.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d19538ccc21819d01deaf88d6a17eae6596a12e9aafdbb97916fb49896d89de9"
+
 [[package]]
 name = "yaml-rust"
 version = "0.4.5"
--- a/README.md
+++ b/README.md
@ -37,20 +37,22 @@ cd artiq
 python setup.py install
 ```

-Locate a recent build of ``nac3artiq-msys2`` from [Hydra](https://nixbld.m-labs.hk) and download ``nac3artiq.zip``. Then extract the contents in the appropriate location:
+Locate a recent build of ``nac3artiq-msys2-pkg`` from [Hydra](https://nixbld.m-labs.hk), download the package, and install it manually with pacman:
 ```
-pacman -S unzip
-wget https://nixbld.m-labs.hk/build/97899/download/1/nac3artiq.zip  # edit the build number
-unzip nac3artiq.zip -d C:/msys64/mingw64/lib/python3.9/site-packages
+wget https://nixbld.m-labs.hk/build/116315/download/1/mingw-w64-x86_64-nac3artiq-1.0-1-any.pkg.tar.zst  # edit the build number
+pacman -U mingw-w64-x86_64-nac3artiq-1.0-1-any.pkg.tar.zst
 ```

-Install additional NAC3 dependencies:
+Install ``lld-msys2`` manually:
 ```
-pacman -S mingw-w64-x86_64-lld
+wget https://nixbld.m-labs.hk/build/115527/download/1/ld.lld.exe
+mv ld.lld.exe C:/msys64/mingw64/bin
 ```

 And you should be good to go.

+Note: This build of NAC3 cannot be used with Anaconda Python nor the python.org binaries for Windows. Those Python versions are compiled with Visual Studio (MSVC) and their ABI is incompatible with the GNU ABI used in this build. We have no plans to support Visual Studio nor the MSVC ABI. If you need a MSVC build, please install the requisite bloated spyware from Microsoft and compile NAC3 yourself.
+
 ## For developers

 This repository contains:
--- a/flake.lock
+++ b/flake.lock
@ -2,11 +2,11 @@
  "nodes": {
    "nixpkgs": {
      "locked": {
-        "lastModified": 1647992509,
-        "narHash": "sha256-AG40Nt5OWz0LBs5p457emOuwLKOvTtcv/2fUdnEN3Ws=",
+        "lastModified": 1649024309,
+        "narHash": "sha256-AWbvj/NHZXVwAnHaVOFlxg7tcNerEKrKBmgGfztSHWM=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "d2caa9377539e3b5ff1272ac3aa2d15f3081069f",
+        "rev": "af0a9bc0e5341855518e9c1734d7ef913e5138b9",
        "type": "github"
      },
      "original": {
--- a/flake.nix
+++ b/flake.nix
@ -8,7 +8,7 @@
      pkgs = import nixpkgs { system = "x86_64-linux"; };
    in rec {
      packages.x86_64-linux = rec {
-        llvm-nac3 = pkgs.callPackage "${self}/llvm" {};
+        llvm-nac3 = pkgs.callPackage ./nix/llvm {};
        nac3artiq = pkgs.python3Packages.toPythonModule (
          pkgs.rustPlatform.buildRustPackage {
            name = "nac3artiq";
@ -48,7 +48,7 @@
        };

        # LLVM PGO support
-        llvm-nac3-instrumented = pkgs.callPackage "${self}/llvm" {
+        llvm-nac3-instrumented = pkgs.callPackage ./nix/llvm {
          stdenv = pkgs.llvmPackages_13.stdenv;
          extraCmakeFlags = [ "-DLLVM_BUILD_INSTRUMENTED=IR" ];
        };
@ -86,7 +86,7 @@
            llvm-profdata merge -o $out/llvm.profdata /build/llvm/build/profiles/*
            '';
        };
-        llvm-nac3-pgo = pkgs.callPackage "${self}/llvm" {
+        llvm-nac3-pgo = pkgs.callPackage ./nix/llvm {
          stdenv = pkgs.llvmPackages_13.stdenv;
          extraCmakeFlags = [ "-DLLVM_PROFDATA_FILE=${nac3artiq-profile}/llvm.profdata" ];
        };
@ -109,7 +109,7 @@
        );
      };

-      packages.x86_64-w64-mingw32 = import ./windows { inherit pkgs; };
+      packages.x86_64-w64-mingw32 = import ./nix/windows { inherit pkgs; };

      devShell.x86_64-linux = pkgs.mkShell {
        name = "nac3-dev-shell";
@ -129,7 +129,7 @@
        ];
      };
      devShells.x86_64-linux.msys2 = pkgs.mkShell {
-        name = "nac3-dev-shell";
+        name = "nac3-dev-shell-msys2";
        buildInputs = with pkgs; [
          curl
          pacman
@ -142,6 +142,8 @@
        inherit (packages.x86_64-linux) llvm-nac3 nac3artiq;
        llvm-nac3-msys2 = packages.x86_64-w64-mingw32.llvm-nac3;
        nac3artiq-msys2 = packages.x86_64-w64-mingw32.nac3artiq;
+        nac3artiq-msys2-pkg = packages.x86_64-w64-mingw32.nac3artiq-pkg;
+        lld-msys2 = packages.x86_64-w64-mingw32.lld;
      };
  };

--- a/nac3artiq/demo/embedding_map.py
+++ b/nac3artiq/demo/embedding_map.py
@ -5,6 +5,7 @@ class EmbeddingMap:
        self.string_map = {}
        self.string_reverse_map = {}
        self.function_map = {}
+        self.attributes_writeback = []

        # preallocate exception names
        self.preallocate_runtime_exception_names(["RuntimeError",
@ -16,7 +17,8 @@ class EmbeddingMap:
                                          "CacheError",
                                          "SPIError",
                                          "0:ZeroDivisionError",
-                                          "0:IndexError"])
+                                          "0:IndexError",
+                                          "0:UnwrapNoneError"])

    def preallocate_runtime_exception_names(self, names):
        for i, name in enumerate(names):
--- a/nac3artiq/demo/min_artiq.py
+++ b/nac3artiq/demo/min_artiq.py
@ -11,6 +11,7 @@ from embedding_map import EmbeddingMap

 __all__ = [
    "Kernel", "KernelInvariant", "virtual",
+    "Option", "Some", "none", "UnwrapNoneError",
    "round64", "floor64", "ceil64",
    "extern", "kernel", "portable", "nac3",
    "rpc", "ms", "us", "ns",
@ -32,6 +33,39 @@ class KernelInvariant(Generic[T]):
 class virtual(Generic[T]):
    pass

+class Option(Generic[T]):
+    _nac3_option: T
+
+    def __init__(self, v: T):
+        self._nac3_option = v
+
+    def is_none(self):
+        return self._nac3_option is None
+    
+    def is_some(self):
+        return not self.is_none()
+    
+    def unwrap(self):
+        if self.is_none():
+            raise UnwrapNoneError()
+        return self._nac3_option
+
+    def __repr__(self) -> str:
+        if self.is_none():
+            return "none"
+        else:
+            return "Some({})".format(repr(self._nac3_option))
+    
+    def __str__(self) -> str:
+        if self.is_none():
+            return "none"
+        else:
+            return "Some({})".format(str(self._nac3_option))
+
+def Some(v: T) -> Option[T]:
+    return Option(v)
+
+none = Option(None)

 def round64(x):
    return round(x)
@ -240,5 +274,10 @@ class KernelContextManager:
    def __exit__(self):
        pass

+@nac3
+class UnwrapNoneError(Exception):
+    """raised when unwrapping a none value"""
+    artiq_builtin = True
+
 parallel = KernelContextManager()
 sequential = KernelContextManager()
--- a/nac3artiq/src/codegen.rs
+++ b/nac3artiq/src/codegen.rs
@ -6,7 +6,7 @@ use nac3core::{
    },
    symbol_resolver::ValueEnum,
    toplevel::{DefinitionId, GenCall},
-    typecheck::typedef::{FunSignature, Type},
+    typecheck::typedef::{FunSignature, FuncArg, Type, TypeEnum}
 };

 use nac3parser::ast::{Expr, ExprKind, Located, Stmt, StmtKind, StrRef};
@ -15,7 +15,9 @@ use inkwell::{
    context::Context, module::Linkage, types::IntType, values::BasicValueEnum, AddressSpace,
 };

-use crate::timeline::TimeFns;
+use pyo3::{PyObject, PyResult, Python, types::{PyDict, PyList}};
+
+use crate::{symbol_resolver::InnerResolver, timeline::TimeFns};

 use std::{
    collections::hash_map::DefaultHasher,
@ -270,8 +272,6 @@ fn gen_rpc_tag<'ctx, 'a>(
                buffer.push(b'l');
                gen_rpc_tag(ctx, *ty, buffer)?;
            }
-            // we should return an error, this will be fixed after improving error message
-            // as this requires returning an error during codegen
            _ => return Err(format!("Unsupported type: {:?}", ctx.unifier.stringify(ty))),
        }
    }
@ -291,7 +291,7 @@ fn rpc_codegen_callback_fn<'ctx, 'a>(
    let int32 = ctx.ctx.i32_type();
    let tag_ptr_type = ctx.ctx.struct_type(&[ptr_type.into(), size_type.into()], false);

-    let service_id = int32.const_int(fun.1 .0 as u64, false);
+    let service_id = int32.const_int(fun.1.0 as u64, false);
    // -- setup rpc tags
    let mut tag = Vec::new();
    if obj.is_some() {
@ -361,7 +361,10 @@ fn rpc_codegen_callback_fn<'ctx, 'a>(
    }
    // default value handling
    for k in keys.into_iter() {
-        mapping.insert(k.name, ctx.gen_symbol_val(generator, &k.default_value.unwrap()).into());
+        mapping.insert(
+            k.name,
+            ctx.gen_symbol_val(generator, &k.default_value.unwrap(), k.ty).into()
+        );
    }
    // reorder the parameters
    let mut real_params = fun
@ -486,6 +489,81 @@ fn rpc_codegen_callback_fn<'ctx, 'a>(
    Ok(Some(result))
 }

+pub fn attributes_writeback<'ctx, 'a>(
+    ctx: &mut CodeGenContext<'ctx, 'a>,
+    generator: &mut dyn CodeGenerator,
+    inner_resolver: &InnerResolver,
+    host_attributes: PyObject,
+) -> Result<(), String> {
+    Python::with_gil(|py| -> PyResult<Result<(), String>> {
+        let host_attributes = host_attributes.cast_as::<PyList>(py)?;
+        let top_levels = ctx.top_level.definitions.read();
+        let globals = inner_resolver.global_value_ids.read();
+        let int32 = ctx.ctx.i32_type();
+        let zero = int32.const_zero();
+        let mut values = Vec::new();
+        let mut scratch_buffer = Vec::new();
+        for (_, val) in globals.iter() {
+            let val = val.as_ref(py);
+            let ty = inner_resolver.get_obj_type(py, val, &mut ctx.unifier, &top_levels, &ctx.primitives)?;
+            if let Err(ty) = ty {
+                return Ok(Err(ty))
+            }
+            let ty = ty.unwrap();
+            match &*ctx.unifier.get_ty(ty) {
+                TypeEnum::TObj { fields, .. } => {
+                    // we only care about primitive attributes
+                    // for non-primitive attributes, they should be in another global
+                    let mut attributes = Vec::new();
+                    let obj = inner_resolver.get_obj_value(py, val, ctx, generator)?.unwrap();
+                    for (name, (field_ty, is_mutable)) in fields.iter() {
+                        if !is_mutable {
+                            continue
+                        }
+                        if gen_rpc_tag(ctx, *field_ty, &mut scratch_buffer).is_ok() {
+                            attributes.push(name.to_string());
+                            let index = ctx.get_attr_index(ty, *name);
+                            values.push((*field_ty, ctx.build_gep_and_load(
+                                            obj.into_pointer_value(),
+                                            &[zero, int32.const_int(index as u64, false)])));
+                        }
+                    }
+                    if !attributes.is_empty() {
+                        let pydict = PyDict::new(py);
+                        pydict.set_item("obj", val)?;
+                        pydict.set_item("fields", attributes)?;
+                        host_attributes.append(pydict)?;
+                    }
+                },
+                TypeEnum::TList { ty: elem_ty } => {
+                    if gen_rpc_tag(ctx, *elem_ty, &mut scratch_buffer).is_ok() {
+                        let pydict = PyDict::new(py);
+                        pydict.set_item("obj", val)?;
+                        host_attributes.append(pydict)?;
+                        values.push((ty, inner_resolver.get_obj_value(py, val, ctx, generator)?.unwrap()));
+                    }
+                },
+                _ => {}
+            }
+        }
+        let fun = FunSignature {
+            args: values.iter().enumerate().map(|(i, (ty, _))| FuncArg {
+                name: i.to_string().into(),
+                ty: *ty,
+                default_value: None
+            }).collect(),
+            ret: ctx.primitives.none,
+            vars: Default::default()
+        };
+        let args: Vec<_> = values.into_iter().map(|(_, val)| (None, ValueEnum::Dynamic(val))).collect();
+        if let Err(e) = rpc_codegen_callback_fn(ctx, None, (&fun, DefinitionId(0)), args, generator) {
+            return Ok(Err(e));
+        }
+        Ok(Ok(()))
+    }).unwrap()?;
+    Ok(())
+}
+
 pub fn rpc_codegen_callback() -> Arc<GenCall> {
    Arc::new(GenCall::new(Box::new(|ctx, obj, fun, args, generator| {
        rpc_codegen_callback_fn(ctx, obj, fun, args, generator)
--- a/nac3artiq/src/lib.rs
+++ b/nac3artiq/src/lib.rs
@ -10,6 +10,7 @@ use inkwell::{
    targets::*,
    OptimizationLevel,
 };
+use nac3core::codegen::gen_func_impl;
 use nac3core::toplevel::builtins::get_exn_constructor;
 use nac3core::typecheck::typedef::{TypeEnum, Unifier};
 use nac3parser::{
@ -36,6 +37,7 @@ use nac3core::{

 use tempfile::{self, TempDir};

+use crate::codegen::attributes_writeback;
 use crate::{
    codegen::{rpc_codegen_callback, ArtiqCodeGenerator},
    symbol_resolver::{InnerResolver, PythonHelper, Resolver, DeferredEvaluationStore},
@ -71,6 +73,7 @@ pub struct PrimitivePythonId {
    exception: u64,
    generic_alias: (u64, u64),
    virtual_id: u64,
+    option: u64,
 }

 type TopLevelComponent = (Stmt, String, PyObject);
@ -373,7 +376,17 @@ impl Nac3 {
                get_attr_id(typing_mod, "_GenericAlias"),
                get_attr_id(types_mod, "GenericAlias"),
            ),
-            none: get_attr_id(builtins_mod, "None"),
+            none: id_fn
+                .call1((builtins_mod
+                    .getattr("globals")
+                    .unwrap()
+                    .call0()
+                    .unwrap()
+                    .get_item("none")
+                    .unwrap(),))
+                .unwrap()
+                .extract()
+                .unwrap(),
            typevar: get_attr_id(typing_mod, "TypeVar"),
            int: get_attr_id(builtins_mod, "int"),
            int32: get_attr_id(numpy_mod, "int32"),
@ -385,6 +398,17 @@ impl Nac3 {
            list: get_attr_id(builtins_mod, "list"),
            tuple: get_attr_id(builtins_mod, "tuple"),
            exception: get_attr_id(builtins_mod, "Exception"),
+            option: id_fn
+                .call1((builtins_mod
+                    .getattr("globals")
+                    .unwrap()
+                    .call0()
+                    .unwrap()
+                    .get_item("Option")
+                    .unwrap(),))
+                .unwrap()
+                .extract()
+                .unwrap(),
        };

        let working_directory = tempfile::Builder::new().prefix("nac3-").tempdir().unwrap();
@ -454,6 +478,8 @@ impl Nac3 {
        let store_obj = embedding_map.getattr("store_object").unwrap().to_object(py);
        let store_str = embedding_map.getattr("store_str").unwrap().to_object(py);
        let store_fun = embedding_map.getattr("store_function").unwrap().to_object(py);
+        let host_attributes = embedding_map.getattr("attributes_writeback").unwrap().to_object(py);
+        let global_value_ids: Arc<RwLock<HashMap<_, _>>> = Arc::new(RwLock::new(HashMap::new()));
        let helper = PythonHelper {
            id_fn: builtins.getattr("id").unwrap().to_object(py),
            len_fn: builtins.getattr("len").unwrap().to_object(py),
@ -474,13 +500,13 @@ impl Nac3 {
            "KeyError",
            "NotImplementedError",
            "OverflowError",
-            "IOError"
+            "IOError",
+            "UnwrapNoneError",
        ];
        add_exceptions(&mut composer, &mut builtins_def, &mut builtins_ty, &exception_names);

        let mut module_to_resolver_cache: HashMap<u64, _> = HashMap::new();

-        let global_value_ids = Arc::new(RwLock::new(HashSet::<u64>::new()));
        let mut rpc_ids = vec![];
        for (stmt, path, module) in self.top_levels.iter() {
            let py_module: &PyAny = module.extract(py)?;
@ -594,7 +620,7 @@ impl Nac3 {
        };
        let mut synthesized =
            parse_program(&synthesized, "__nac3_synthesized_modinit__".to_string().into()).unwrap();
-        let resolver = Arc::new(Resolver(Arc::new(InnerResolver {
+        let inner_resolver = Arc::new(InnerResolver {
            id_to_type: builtins_ty.clone().into(),
            id_to_def: builtins_def.clone().into(),
            pyid_to_def: self.pyid_to_def.clone(),
@ -611,17 +637,18 @@ impl Nac3 {
            string_store: self.string_store.clone(),
            exception_ids: self.exception_ids.clone(),
            deferred_eval_store: self.deferred_eval_store.clone(),
-        }))) as Arc<dyn SymbolResolver + Send + Sync>;
+        });
+        let resolver = Arc::new(Resolver(inner_resolver.clone())) as Arc<dyn SymbolResolver + Send + Sync>;
        let (_, def_id, _) = composer
            .register_top_level(synthesized.pop().unwrap(), Some(resolver.clone()), "".into())
            .unwrap();

-        let signature =
+        let fun_signature =
            FunSignature { args: vec![], ret: self.primitive.none, vars: HashMap::new() };
        let mut store = ConcreteTypeStore::new();
        let mut cache = HashMap::new();
        let signature =
-            store.from_signature(&mut composer.unifier, &self.primitive, &signature, &mut cache);
+            store.from_signature(&mut composer.unifier, &self.primitive, &fun_signature, &mut cache);
        let signature = store.add_cty(signature);

        if let Err(e) = composer.start_analysis(true) {
@ -698,12 +725,29 @@ impl Nac3 {
            symbol_name: "__modinit__".to_string(),
            body: instance.body,
            signature,
-            resolver,
+            resolver: resolver.clone(),
            store,
            unifier_index: instance.unifier_id,
            calls: instance.calls,
            id: 0,
        };
+
+        let mut store = ConcreteTypeStore::new();
+        let mut cache = HashMap::new();
+        let signature =
+            store.from_signature(&mut composer.unifier, &self.primitive, &fun_signature, &mut cache);
+        let signature = store.add_cty(signature);
+        let attributes_writeback_task = CodeGenTask {
+            subst: Default::default(),
+            symbol_name: "attributes_writeback".to_string(),
+            body: Arc::new(Default::default()),
+            signature,
+            resolver,
+            store,
+            unifier_index: instance.unifier_id,
+            calls: Arc::new(Default::default()),
+            id: 0,
+        };
        let isa = self.isa;
        let working_directory = self.working_directory.path().to_owned();

@ -723,14 +767,27 @@ impl Nac3 {
            .map(|s| Box::new(ArtiqCodeGenerator::new(s.to_string(), size_t, self.time_fns)))
            .collect();

+        let membuffer = membuffers.clone();
        py.allow_threads(|| {
            let (registry, handles) = WorkerRegistry::create_workers(threads, top_level.clone(), f);
            registry.add_task(task);
            registry.wait_tasks_complete(handles);
+
+            let mut generator = ArtiqCodeGenerator::new("attributes_writeback".to_string(), size_t, self.time_fns);
+            let context = inkwell::context::Context::create();
+            let module = context.create_module("attributes_writeback");
+            let builder = context.create_builder();
+            let (_, module, _) = gen_func_impl(&context, &mut generator, &registry, builder, module,
+                attributes_writeback_task, |generator, ctx| {
+                    attributes_writeback(ctx, generator, inner_resolver.as_ref(), host_attributes)
+                }).unwrap();
+            let buffer = module.write_bitcode_to_memory();
+            let buffer = buffer.as_slice().into();
+            membuffer.lock().push(buffer);
        });

-        let buffers = membuffers.lock();
        let context = inkwell::context::Context::create();
+        let buffers = membuffers.lock();
        let main = context
            .create_module_from_ir(MemoryBuffer::create_from_memory_range(&buffers[0], "main"))
            .unwrap();
@ -742,6 +799,11 @@ impl Nac3 {
            main.link_in_module(other)
                .map_err(|err| CompileError::new_err(err.to_string()))?;
        }
+        let builder = context.create_builder();
+        let modinit_return = main.get_function("__modinit__").unwrap().get_last_basic_block().unwrap().get_terminator().unwrap();
+        builder.position_before(&modinit_return);
+        builder.build_call(main.get_function("attributes_writeback").unwrap(), &[], "attributes_writeback");
+
        main.link_in_module(load_irrt(&context))
            .map_err(|err| CompileError::new_err(err.to_string()))?;

@ -805,7 +867,11 @@ impl Nac3 {
            );
        }

-        if let Ok(linker_status) = Command::new("ld.lld").args(linker_args).status() {
+        #[cfg(not(windows))]
+        let lld_command = "ld.lld";
+        #[cfg(windows)]
+        let lld_command = "ld.lld.exe";
+        if let Ok(linker_status) = Command::new(lld_command).args(linker_args).status() {
            if !linker_status.success() {
                return Err(CompileError::new_err("failed to start linker"));
            }
--- a/nac3artiq/src/symbol_resolver.rs
+++ b/nac3artiq/src/symbol_resolver.rs
@ -15,7 +15,7 @@ use pyo3::{
    PyAny, PyObject, PyResult, Python,
 };
 use std::{
-    collections::{HashMap, HashSet},
+    collections::HashMap,
    sync::{
        Arc,
        atomic::{AtomicBool, Ordering::Relaxed}
@ -54,7 +54,7 @@ pub struct InnerResolver {
    pub id_to_pyval: RwLock<HashMap<StrRef, (u64, PyObject)>>,
    pub id_to_primitive: RwLock<HashMap<u64, PrimitiveValue>>,
    pub field_to_val: RwLock<HashMap<(u64, StrRef), Option<(u64, PyObject)>>>,
-    pub global_value_ids: Arc<RwLock<HashSet<u64>>>,
+    pub global_value_ids: Arc<RwLock<HashMap<u64, PyObject>>>,
    pub class_names: Mutex<HashMap<StrRef, Type>>,
    pub pyid_to_def: Arc<RwLock<HashMap<u64, DefinitionId>>>,
    pub pyid_to_type: Arc<RwLock<HashMap<u64, Type>>>,
@ -279,6 +279,10 @@ impl InnerResolver {
        } else if ty_id == self.primitive_ids.tuple {
            // do not handle type var param and concrete check here
            Ok(Ok((unifier.add_ty(TypeEnum::TTuple { ty: vec![] }), false)))
+        } else if ty_id == self.primitive_ids.option {
+            Ok(Ok((primitives.option, false)))
+        } else if ty_id == self.primitive_ids.none {
+            unreachable!("none cannot be typeid")
        } else if let Some(def_id) = self.pyid_to_def.read().get(&ty_id).cloned() {
            let def = defs[def_id.0].read();
            if let TopLevelDef::Class { object_id, type_vars, fields, methods, .. } = &*def {
@ -499,7 +503,7 @@ impl InnerResolver {
        }
    }

-    fn get_obj_type(
+    pub fn get_obj_type(
        &self,
        py: Python,
        obj: &PyAny,
@ -508,8 +512,8 @@ impl InnerResolver {
        primitives: &PrimitiveStore,
    ) -> PyResult<Result<Type, String>> {
        let ty = self.helper.type_fn.call1(py, (obj,)).unwrap();
-        let ty_id: u64 = self.helper.id_fn.call1(py, (ty.clone(),))?.extract(py)?;
-        if let Some(ty) = self.pyid_to_type.read().get(&ty_id) {
+        let py_obj_id: u64 = self.helper.id_fn.call1(py, (obj,))?.extract(py)?;
+        if let Some(ty) = self.pyid_to_type.read().get(&py_obj_id) {
            return Ok(Ok(*ty))
        }
        let (extracted_ty, inst_check) = match self.get_pyty_obj_type(
@ -569,7 +573,54 @@ impl InnerResolver {
                let types = types?;
                Ok(types.map(|types| unifier.add_ty(TypeEnum::TTuple { ty: types })))
            }
+            // special handling for option type since its class member layout in python side
+            // is special and cannot be mapped directly to a nac3 type as below
+            (TypeEnum::TObj { obj_id, params, .. }, false)
+                if *obj_id == primitives.option.get_obj_id(unifier) =>
+            {
+                let field_data = match obj.getattr("_nac3_option") {
+                    Ok(d) => d,
+                    // we use `none = Option(None)`, so the obj always have attr `_nac3_option`
+                    Err(_) => unreachable!("cannot be None")
+                };
+                // if is `none`
+                let zelf_id: u64 = self.helper.id_fn.call1(py, (obj,))?.extract(py)?;
+                if zelf_id == self.primitive_ids.none {
+                    if let TypeEnum::TObj { params, .. } =
+                        unifier.get_ty_immutable(primitives.option).as_ref()
+                    {
+                        let var_map = params
+                            .iter()
+                            .map(|(id_var, ty)| {
+                                if let TypeEnum::TVar { id, range, name, loc, .. } = &*unifier.get_ty(*ty) {
+                                    assert_eq!(*id, *id_var);
+                                    (*id, unifier.get_fresh_var_with_range(range, *name, *loc).0)
+                                } else {
+                                    unreachable!()
+                                }
+                            })
+                            .collect::<HashMap<_, _>>();
+                        return Ok(Ok(unifier.subst(primitives.option, &var_map).unwrap()))
+                    } else {
+                        unreachable!("must be tobj")
+                    }
+                }
+
+                let ty = match self.get_obj_type(py, field_data, unifier, defs, primitives)? {
+                    Ok(t) => t,
+                    Err(e) => {
+                        return Ok(Err(format!(
+                            "error when getting type of the option object ({})",
+                            e
+                        )))
+                    }
+                };
+                let new_var_map: HashMap<_, _> = params.iter().map(|(id, _)| (*id, ty)).collect();
+                let res = unifier.subst(extracted_ty, &new_var_map).unwrap_or(extracted_ty);
+                Ok(Ok(res))
+            }
            (TypeEnum::TObj { params, fields, .. }, false) => {
+                self.pyid_to_type.write().insert(py_obj_id, extracted_ty);
                let var_map = params
                    .iter()
                    .map(|(id_var, ty)| {
@ -623,13 +674,19 @@ impl InnerResolver {
                    let extracted_ty = unifier.subst(extracted_ty, &var_map).unwrap_or(extracted_ty);
                    Ok(Ok(extracted_ty))
                };
-                instantiate_obj()
+                let result = instantiate_obj();
+                // update/remove the cache according to the result
+                match result {
+                    Ok(Ok(ty)) => self.pyid_to_type.write().insert(py_obj_id, ty),
+                    _ => self.pyid_to_type.write().remove(&py_obj_id)
+                };
+                result
            }
            _ => Ok(Ok(extracted_ty)),
        }
    }

-    fn get_obj_value<'ctx, 'a>(
+    pub fn get_obj_value<'ctx, 'a>(
        &self,
        py: Python,
        obj: &PyAny,
@ -697,13 +754,13 @@ impl InnerResolver {
                .struct_type(&[ty.ptr_type(AddressSpace::Generic).into(), size_t.into()], false);

            {
-                if self.global_value_ids.read().contains(&id) {
+                if self.global_value_ids.read().contains_key(&id) {
                    let global = ctx.module.get_global(&id_str).unwrap_or_else(|| {
                        ctx.module.add_global(arr_ty, Some(AddressSpace::Generic), &id_str)
                    });
                    return Ok(Some(global.as_pointer_value().into()));
                } else {
-                    self.global_value_ids.write().insert(id);
+                    self.global_value_ids.write().insert(id, obj.into());
                }
            }

@ -751,50 +808,46 @@ impl InnerResolver {

            Ok(Some(global.as_pointer_value().into()))
        } else if ty_id == self.primitive_ids.tuple {
-            let id_str = id.to_string();
-
-            if let Some(global) = ctx.module.get_global(&id_str) {
-                return Ok(Some(global.as_pointer_value().into()));
-            }
-
            let elements: &PyTuple = obj.cast_as()?;
-            let types: Result<Result<Vec<_>, _>, _> = elements
-                .iter()
-                .enumerate()
-                .map(|(i, elem)| {
-                    self.get_obj_type(
-                        py,
-                        elem,
-                        &mut ctx.unifier,
-                        &ctx.top_level.definitions.read(),
-                        &ctx.primitives,
-                    )
-                    .map_err(|e| super::CompileError::new_err(format!("Error getting element {}: {}", i, e)))
-                    .map(|ty| ty.map(|ty| ctx.get_llvm_type(generator, ty)))
-                })
-                .collect();
-            let types = types?.unwrap();
-            let ty = ctx.ctx.struct_type(&types, false);
-
-            {
-                if self.global_value_ids.read().contains(&id) {
-                    let global = ctx.module.get_global(&id_str).unwrap_or_else(|| {
-                        ctx.module.add_global(ty, Some(AddressSpace::Generic), &id_str)
-                    });
-                    return Ok(Some(global.as_pointer_value().into()));
-                } else {
-                    self.global_value_ids.write().insert(id);
-                }
-            }
-
            let val: Result<Option<Vec<_>>, _> =
                elements.iter().enumerate().map(|(i, elem)| self.get_obj_value(py, elem, ctx, generator).map_err(|e|
                        super::CompileError::new_err(format!("Error getting element {}: {}", i, e)))).collect();
            let val = val?.unwrap();
            let val = ctx.ctx.const_struct(&val, false);
-            let global = ctx.module.add_global(ty, Some(AddressSpace::Generic), &id_str);
-            global.set_initializer(&val);
-            Ok(Some(global.as_pointer_value().into()))
+            Ok(Some(val.into()))
+        } else if ty_id == self.primitive_ids.option {
+            if id == self.primitive_ids.none {
+                // for option type, just a null ptr, whose type needs to be casted in codegen
+                // according to the type info attached in the ast
+                Ok(Some(ctx.ctx.i8_type().ptr_type(AddressSpace::Generic).const_null().into()))
+            } else {
+                match self
+                    .get_obj_value(py, obj.getattr("_nac3_option").unwrap(), ctx, generator)
+                    .map_err(|e| {
+                        super::CompileError::new_err(format!(
+                            "Error getting value of Option object: {}",
+                            e
+                        ))
+                    })? {
+                    Some(v) => {
+                        let global_str = format!("{}_option", id);
+                        {
+                            if self.global_value_ids.read().contains_key(&id) {
+                                let global = ctx.module.get_global(&global_str).unwrap_or_else(|| {
+                                    ctx.module.add_global(v.get_type(), Some(AddressSpace::Generic), &global_str)
+                                });
+                                return Ok(Some(global.as_pointer_value().into()));
+                            } else {
+                                self.global_value_ids.write().insert(id, obj.into());
+                            }
+                        }
+                        let global = ctx.module.add_global(v.get_type(), Some(AddressSpace::Generic), &global_str);
+                        global.set_initializer(&v);
+                        Ok(Some(global.as_pointer_value().into()))
+                    },
+                    None => Ok(None),
+                }
+            }
        } else {
            let id_str = id.to_string();

@ -812,13 +865,13 @@ impl InnerResolver {
                .get_element_type()
                .into_struct_type();
            {
-                if self.global_value_ids.read().contains(&id) {
+                if self.global_value_ids.read().contains_key(&id) {
                    let global = ctx.module.get_global(&id_str).unwrap_or_else(|| {
                        ctx.module.add_global(ty, Some(AddressSpace::Generic), &id_str)
                    });
                    return Ok(Some(global.as_pointer_value().into()));
                } else {
-                    self.global_value_ids.write().insert(id);
+                    self.global_value_ids.write().insert(id, obj.into());
                }
            }
            // should be classes
@ -827,15 +880,32 @@ impl InnerResolver {
            if let TopLevelDef::Class { fields, .. } = &*definition {
                let values: Result<Option<Vec<_>>, _> = fields
                    .iter()
-                    .map(|(name, _, _)| {
-                        self.get_obj_value(py, obj.getattr(&name.to_string())?, ctx, generator).map_err(|e|
-                            super::CompileError::new_err(format!("Error getting field {}: {}", name, e)))
+                    .map(|(name, ty, _)| {
+                        let v = self.get_obj_value(py, obj.getattr(&name.to_string())?, ctx, generator)
+                            .map_err(|e| super::CompileError::new_err(format!("Error getting field {}: {}", name, e)));
+                        match (v, ctx.unifier.get_ty_immutable(*ty).as_ref()) {
+                            (Ok(Some(v)), TypeEnum::TObj { obj_id, params, .. })
+                                if *obj_id == ctx.primitives.option.get_obj_id(&ctx.unifier) =>
+                            {
+                                let actual_ptr_ty = ctx
+                                    .get_llvm_type(generator, *params.iter().next().unwrap().1)
+                                    .ptr_type(AddressSpace::Generic);
+                                Ok(Some(ctx.builder.build_bitcast(
+                                    v,
+                                    actual_ptr_ty,
+                                    "option_none_ptr_cast",
+                                )))
+                            }
+                            (v, _) => v,
+                        }
                    })
                    .collect();
                let values = values?;
                if let Some(values) = values {
                    let val = ty.const_named_struct(&values);
-                    let global = ctx.module.add_global(ty, Some(AddressSpace::Generic), &id_str);
+                    let global = ctx.module.get_global(&id_str).unwrap_or_else(|| {
+                        ctx.module.add_global(ty, Some(AddressSpace::Generic), &id_str)
+                    });
                    global.set_initializer(&val);
                    Ok(Some(global.as_pointer_value().into()))
                } else {
@ -852,6 +922,7 @@ impl InnerResolver {
        py: Python,
        obj: &PyAny,
    ) -> PyResult<Result<SymbolValue, String>> {
+        let id: u64 = self.helper.id_fn.call1(py, (obj,))?.extract(py)?;
        let ty_id: u64 =
            self.helper.id_fn.call1(py, (self.helper.type_fn.call1(py, (obj,))?,))?.extract(py)?;
        Ok(if ty_id == self.primitive_ids.int || ty_id == self.primitive_ids.int32 {
@ -860,6 +931,12 @@ impl InnerResolver {
        } else if ty_id == self.primitive_ids.int64 {
            let val: i64 = obj.extract()?;
            Ok(SymbolValue::I64(val))
+        } else if ty_id == self.primitive_ids.uint32 {
+            let val: u32 = obj.extract()?;
+            Ok(SymbolValue::U32(val))
+        } else if ty_id == self.primitive_ids.uint64 {
+            let val: u64 = obj.extract()?;
+            Ok(SymbolValue::U64(val))
        } else if ty_id == self.primitive_ids.bool {
            let val: bool = obj.extract()?;
            Ok(SymbolValue::Bool(val))
@ -870,13 +947,17 @@ impl InnerResolver {
            let elements: &PyTuple = obj.cast_as()?;
            let elements: Result<Result<Vec<_>, String>, _> =
                elements.iter().map(|elem| self.get_default_param_obj_value(py, elem)).collect();
-            let elements = match elements? {
-                Ok(el) => el,
-                Err(err) => return Ok(Err(err)),
-            };
-            Ok(SymbolValue::Tuple(elements))
+            elements?.map(SymbolValue::Tuple)
+        } else if ty_id == self.primitive_ids.option {
+            if id == self.primitive_ids.none {
+                Ok(SymbolValue::OptionNone)
+            } else {
+                self
+                    .get_default_param_obj_value(py, obj.getattr("_nac3_option").unwrap())?
+                    .map(|v| SymbolValue::OptionSome(Box::new(v)))
+            }
        } else {
-            Err("only primitives values and tuple can be default parameter value".into())
+            Err("only primitives values, option and tuple can be default parameter value".into())
        })
    }
 }
@ -892,8 +973,9 @@ impl SymbolResolver for Resolver {
                    for (key, val) in members.iter() {
                        let key: &str = key.extract()?;
                        if key == id.to_string() {
-                            sym_value =
-                                Some(self.0.get_default_param_obj_value(py, val).unwrap().unwrap());
+                            if let Ok(Ok(v)) = self.0.get_default_param_obj_value(py, val) {
+                                sym_value = Some(v)
+                            }
                            break;
                        }
                    }
@ -901,7 +983,7 @@ impl SymbolResolver for Resolver {
                })
                .unwrap()
            }
-            _ => unimplemented!("other type of expr not supported at {}", expr.location),
+            _ => unreachable!("only for resolving names"),
        }
    }

--- a/nac3core/src/codegen/expr.rs
+++ b/nac3core/src/codegen/expr.rs
@ -91,6 +91,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
        &mut self,
        generator: &mut dyn CodeGenerator,
        val: &SymbolValue,
+        ty: Type,
    ) -> BasicValueEnum<'ctx> {
        match val {
            SymbolValue::I32(v) => self.ctx.i32_type().const_int(*v as u64, true).into(),
@ -107,7 +108,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                ty.const_named_struct(&[str_ptr, size.into()]).into()
            }
            SymbolValue::Tuple(ls) => {
-                let vals = ls.iter().map(|v| self.gen_symbol_val(generator, v)).collect_vec();
+                let vals = ls.iter().map(|v| self.gen_symbol_val(generator, v, ty)).collect_vec();
                let fields = vals.iter().map(|v| v.get_type()).collect_vec();
                let ty = self.ctx.struct_type(&fields, false);
                let ptr = self.builder.build_alloca(ty, "tuple");
@ -124,6 +125,37 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                }
                self.builder.build_load(ptr, "tup_val")
            }
+            SymbolValue::OptionSome(v) => {
+                let ty = match self.unifier.get_ty_immutable(ty).as_ref() {
+                    TypeEnum::TObj { obj_id, params, .. }
+                        if *obj_id == self.primitives.option.get_obj_id(&self.unifier) =>
+                    {
+                        *params.iter().next().unwrap().1
+                    }
+                    _ => unreachable!("must be option type"),
+                };
+                let val = self.gen_symbol_val(generator, v, ty);
+                let ptr = self.builder.build_alloca(val.get_type(), "default_opt_some");
+                self.builder.build_store(ptr, val);
+                ptr.into()
+            }
+            SymbolValue::OptionNone => {
+                let ty = match self.unifier.get_ty_immutable(ty).as_ref() {
+                    TypeEnum::TObj { obj_id, params, .. }
+                        if *obj_id == self.primitives.option.get_obj_id(&self.unifier) =>
+                    {
+                        *params.iter().next().unwrap().1
+                    }
+                    _ => unreachable!("must be option type"),
+                };
+                let actual_ptr_type =
+                    self.get_llvm_type(generator, ty).ptr_type(AddressSpace::Generic);
+                self.builder.build_bitcast(
+                    self.ctx.i8_type().ptr_type(AddressSpace::Generic).const_null(),
+                    actual_ptr_type,
+                    "default_opt_none",
+                )
+            }
        }
    }

@ -138,6 +170,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
            &mut self.unifier,
            self.top_level,
            &mut self.type_cache,
+            &self.primitives,
            ty,
        )
    }
@ -205,6 +238,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {

    pub fn gen_int_ops(
        &mut self,
+        generator: &mut dyn CodeGenerator,
        op: &Operator,
        lhs: BasicValueEnum<'ctx>,
        rhs: BasicValueEnum<'ctx>,
@ -240,7 +274,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
            (Operator::RShift, _) => self.builder.build_right_shift(lhs, rhs, true, "rshift").into(),
            (Operator::FloorDiv, true) => self.builder.build_int_signed_div(lhs, rhs, "floordiv").into(),
            (Operator::FloorDiv, false) => self.builder.build_int_unsigned_div(lhs, rhs, "floordiv").into(),
-            (Operator::Pow, s) => integer_power(self, lhs, rhs, s).into(),
+            (Operator::Pow, s) => integer_power(generator, self, lhs, rhs, s).into(),
            // special implementation?
            (Operator::MatMult, _) => unreachable!(),
        }
@ -354,17 +388,17 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
        }
    }

-    pub fn gen_string<G: CodeGenerator, S: Into<String>>(
+    pub fn gen_string<S: Into<String>>(
        &mut self,
-        generator: &mut G,
+        generator: &mut dyn CodeGenerator,
        s: S,
    ) -> BasicValueEnum<'ctx> {
        self.gen_const(generator, &nac3parser::ast::Constant::Str(s.into()), self.primitives.str)
    }

-    pub fn raise_exn<G: CodeGenerator>(
+    pub fn raise_exn(
        &mut self,
-        generator: &mut G,
+        generator: &mut dyn CodeGenerator,
        name: &str,
        msg: BasicValueEnum<'ctx>,
        params: [Option<IntValue<'ctx>>; 3],
@ -401,14 +435,27 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
        gen_raise(generator, self, Some(&zelf.into()), loc);
    }

-    pub fn make_assert<G: CodeGenerator>(
+    pub fn make_assert(
        &mut self,
-        generator: &mut G,
+        generator: &mut dyn CodeGenerator,
        cond: IntValue<'ctx>,
        err_name: &str,
        err_msg: &str,
        params: [Option<IntValue<'ctx>>; 3],
        loc: Location,
+    ) {
+        let err_msg = self.gen_string(generator, err_msg);
+        self.make_assert_impl(generator, cond, err_name, err_msg, params, loc)
+    }
+
+    pub fn make_assert_impl(
+        &mut self,
+        generator: &mut dyn CodeGenerator,
+        cond: IntValue<'ctx>,
+        err_name: &str,
+        err_msg: BasicValueEnum<'ctx>,
+        params: [Option<IntValue<'ctx>>; 3],
+        loc: Location,
    ) {
        let i1 = self.ctx.bool_type();
        let i1_true = i1.const_all_ones();
@ -435,7 +482,6 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
        let exn_block = self.ctx.append_basic_block(current_fun, "fail");
        self.builder.build_conditional_branch(cond, then_block, exn_block);
        self.builder.position_at_end(exn_block);
-        let err_msg = self.gen_string(generator, err_msg);
        self.raise_exn(generator, err_name, err_msg, params, loc);
        self.builder.position_at_end(then_block);
    }
@ -592,7 +638,7 @@ pub fn gen_call<'ctx, 'a, G: CodeGenerator>(
                    }
                    mapping.insert(
                        k.name,
-                        ctx.gen_symbol_val(generator, &k.default_value.unwrap()).into(),
+                        ctx.gen_symbol_val(generator, &k.default_value.unwrap(), k.ty).into(),
                    );
                }
                // reorder the parameters
@ -895,23 +941,20 @@ pub fn gen_binop_expr<'ctx, 'a, G: CodeGenerator>(
    // which would be unchanged until further unification, which we would never do
    // when doing code generation for function instances
    Ok(if ty1 == ty2 && [ctx.primitives.int32, ctx.primitives.int64].contains(&ty1) {
-        ctx.gen_int_ops(op, left, right, true)
+        ctx.gen_int_ops(generator, op, left, right, true)
    } else if ty1 == ty2 && [ctx.primitives.uint32, ctx.primitives.uint64].contains(&ty1) {
-        ctx.gen_int_ops(op, left, right, false)
+        ctx.gen_int_ops(generator, op, left, right, false)
    } else if ty1 == ty2 && ctx.primitives.float == ty1 {
        ctx.gen_float_ops(op, left, right)
    } else if ty1 == ctx.primitives.float && ty2 == ctx.primitives.int32 {
        // Pow is the only operator that would pass typecheck between float and int
        assert!(*op == Operator::Pow);
-        // TODO: throw exception when rhs is out of i16 bound
-        // since llvm intrinsic only support to i16 for f64
-        let i16_t = ctx.ctx.i16_type();
-        let pow_intr = ctx.module.get_function("llvm.powi.f64.i16").unwrap_or_else(|| {
+        let i32_t = ctx.ctx.i32_type();
+        let pow_intr = ctx.module.get_function("llvm.powi.f64.i32").unwrap_or_else(|| {
            let f64_t = ctx.ctx.f64_type();
-            let ty = f64_t.fn_type(&[f64_t.into(), i16_t.into()], false);
-            ctx.module.add_function("llvm.powi.f64.i16", ty, None)
+            let ty = f64_t.fn_type(&[f64_t.into(), i32_t.into()], false);
+            ctx.module.add_function("llvm.powi.f64.i32", ty, None)
        });
-        let right = ctx.builder.build_int_truncate(right.into_int_value(), i16_t, "r_pow");
        ctx.builder
            .build_call(pow_intr, &[left.into(), right.into()], "f_pow_i")
            .try_as_basic_value()
@ -927,6 +970,7 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
    ctx: &mut CodeGenContext<'ctx, 'a>,
    expr: &Expr<Option<Type>>,
 ) -> Result<Option<ValueEnum<'ctx>>, String> {
+    ctx.current_loc = expr.location;
    let int32 = ctx.ctx.i32_type();
    let zero = int32.const_int(0, false);
    Ok(Some(match &expr.node {
@ -934,23 +978,45 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
            let ty = expr.custom.unwrap();
            ctx.gen_const(generator, value, ty).into()
        }
+        ExprKind::Name { id, .. } if id == &"none".into() => {
+            match (
+                ctx.unifier.get_ty(expr.custom.unwrap()).as_ref(),
+                ctx.unifier.get_ty(ctx.primitives.option).as_ref(),
+            ) {
+                (
+                    TypeEnum::TObj { obj_id, params, .. },
+                    TypeEnum::TObj { obj_id: opt_id, .. },
+                ) if *obj_id == *opt_id => ctx
+                    .get_llvm_type(generator, *params.iter().next().unwrap().1)
+                    .ptr_type(AddressSpace::Generic)
+                    .const_null()
+                    .into(),
+                _ => unreachable!("must be option type"),
+            }
+        }
        ExprKind::Name { id, .. } => match ctx.var_assignment.get(id) {
            Some((ptr, None, _)) => ctx.builder.build_load(*ptr, "load").into(),
            Some((_, Some(static_value), _)) => ValueEnum::Static(static_value.clone()),
            None => {
                let resolver = ctx.resolver.clone();
                let val = resolver.get_symbol_value(*id, ctx).unwrap();
-                // if is tuple, need to deref it to handle tuple as value
-                if let (TypeEnum::TTuple { .. }, BasicValueEnum::PointerValue(ptr)) = (
-                    &*ctx.unifier.get_ty(expr.custom.unwrap()),
-                    resolver
-                        .get_symbol_value(*id, ctx)
-                        .unwrap()
-                        .to_basic_value_enum(ctx, generator)?,
-                ) {
-                    ctx.builder.build_load(ptr, "tup_val").into()
-                } else {
-                    val
+                // if is option, need to cast pointer to handle None
+                match &*ctx.unifier.get_ty(expr.custom.unwrap()) {
+                    TypeEnum::TObj { obj_id, params, .. }
+                        if *obj_id == ctx.primitives.option.get_obj_id(&ctx.unifier) =>
+                    {
+                        if let BasicValueEnum::PointerValue(ptr) = val.to_basic_value_enum(ctx, generator)? {
+                            let actual_ptr_ty = ctx.get_llvm_type(
+                                generator,
+                                *params.iter().next().unwrap().1,
+                            )
+                            .ptr_type(AddressSpace::Generic);
+                            ctx.builder.build_bitcast(ptr, actual_ptr_ty, "option_ptr_cast").into()
+                        } else {
+                            unreachable!("option obj must be ptr")
+                        }
+                    }
+                    _ => val,
                }
            }
        },
@ -962,7 +1028,7 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                .map(|x| {
                    generator
                        .gen_expr(ctx, x)
-                        .map_or_else(|e| Err(e), |v| v.unwrap().to_basic_value_enum(ctx, generator))
+                        .map_or_else(Err, |v| v.unwrap().to_basic_value_enum(ctx, generator))
                })
                .collect::<Result<Vec<_>, _>>()?;
            let ty = if elements.is_empty() {
@ -995,7 +1061,7 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                .map(|x| {
                    generator
                        .gen_expr(ctx, x)
-                        .map_or_else(|e| Err(e), |v| v.unwrap().to_basic_value_enum(ctx, generator))
+                        .map_or_else(Err, |v| v.unwrap().to_basic_value_enum(ctx, generator))
                })
                .collect::<Result<Vec<_>, _>>()?;
            let element_ty = element_val.iter().map(BasicValueEnum::get_type).collect_vec();
@ -1023,7 +1089,7 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                        v.into_pointer_value(),
                        &[zero, int32.const_int(index as u64, false)],
                    ))) as Result<_, String>
-                }, |v| Ok(v))?,
+                }, Ok)?,
                ValueEnum::Dynamic(v) => {
                    let index = ctx.get_attr_index(value.custom.unwrap(), *attr);
                    ValueEnum::Dynamic(ctx.build_gep_and_load(
@ -1204,21 +1270,44 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                .unwrap()
                .to_basic_value_enum(ctx, generator)?
                .into_int_value();
+            let body_ty = body.custom.unwrap();
+            let is_none = ctx.unifier.get_representative(body_ty) == ctx.primitives.none;
+            let result = if !is_none {
+                let llvm_ty = ctx.get_llvm_type(generator, body_ty);
+                Some(ctx.builder.build_alloca(llvm_ty, "if_exp_result"))
+            } else {
+                None
+            };
            let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
            let then_bb = ctx.ctx.append_basic_block(current, "then");
            let else_bb = ctx.ctx.append_basic_block(current, "else");
            let cont_bb = ctx.ctx.append_basic_block(current, "cont");
            ctx.builder.build_conditional_branch(test, then_bb, else_bb);
            ctx.builder.position_at_end(then_bb);
-            let a = generator.gen_expr(ctx, body)?.unwrap().to_basic_value_enum(ctx, generator)?;
+            let a = generator.gen_expr(ctx, body)?;
+            match result {
+                None => None,
+                Some(v) => {
+                    let a = a.unwrap().to_basic_value_enum(ctx, generator)?;
+                    Some(ctx.builder.build_store(v, a))
+                }
+            };
            ctx.builder.build_unconditional_branch(cont_bb);
            ctx.builder.position_at_end(else_bb);
-            let b = generator.gen_expr(ctx, orelse)?.unwrap().to_basic_value_enum(ctx, generator)?;
+            let b = generator.gen_expr(ctx, orelse)?;
+            match result {
+                None => None,
+                Some(v) => {
+                    let b = b.unwrap().to_basic_value_enum(ctx, generator)?;
+                    Some(ctx.builder.build_store(v, b))
+                }
+            };
            ctx.builder.build_unconditional_branch(cont_bb);
            ctx.builder.position_at_end(cont_bb);
-            let phi = ctx.builder.build_phi(a.get_type(), "ifexpr");
-            phi.add_incoming(&[(&a, then_bb), (&b, else_bb)]);
-            phi.as_basic_value().into()
+            match result {
+                None => return Ok(None),
+                Some(v) => return Ok(Some(ctx.builder.build_load(v, "if_exp_val_load").into()))
+            }
        }
        ExprKind::Call { func, args, keywords } => {
            let mut params = args
@ -1307,6 +1396,7 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                    let (start, end, step) =
                        handle_slice_indices(lower, upper, step, ctx, generator, v)?;
                    let length = calculate_len_for_slice_range(
+                        generator,
                        ctx,
                        start,
                        ctx.builder
@ -1328,8 +1418,8 @@ pub fn gen_expr<'ctx, 'a, G: CodeGenerator>(
                    let res_ind =
                        handle_slice_indices(&None, &None, &None, ctx, generator, res_array_ret)?;
                    list_slice_assignment(
+                        generator,
                        ctx,
-                        generator.get_size_type(ctx.ctx),
                        ty,
                        res_array_ret,
                        res_ind,
--- a/nac3core/src/codegen/irrt/mod.rs
+++ b/nac3core/src/codegen/irrt/mod.rs
@ -6,7 +6,7 @@ use inkwell::{
    context::Context,
    memory_buffer::MemoryBuffer,
    module::Module,
-    types::{BasicTypeEnum, IntType},
+    types::BasicTypeEnum,
    values::{IntValue, PointerValue},
    AddressSpace, IntPredicate,
 };
@ -34,6 +34,7 @@ pub fn load_irrt(ctx: &Context) -> Module {
 // repeated squaring method adapted from GNU Scientific Library:
 // https://git.savannah.gnu.org/cgit/gsl.git/tree/sys/pow_int.c
 pub fn integer_power<'ctx, 'a>(
+    generator: &mut dyn CodeGenerator,
    ctx: &mut CodeGenContext<'ctx, 'a>,
    base: IntValue<'ctx>,
    exp: IntValue<'ctx>,
@ -51,7 +52,21 @@ pub fn integer_power<'ctx, 'a>(
        let fn_type = base_type.fn_type(&[base_type.into(), base_type.into()], false);
        ctx.module.add_function(symbol, fn_type, None)
    });
-    // TODO: throw exception when exp < 0
+    // throw exception when exp < 0
+    let ge_zero = ctx.builder.build_int_compare(
+        IntPredicate::SGE,
+        exp,
+        exp.get_type().const_zero(),
+        "assert_int_pow_ge_0",
+    );
+    ctx.make_assert(
+        generator,
+        ge_zero,
+        "0:ValueError",
+        "integer power must be positive or zero",
+        [None, None, None],
+        ctx.current_loc,
+    );
    ctx.builder
        .build_call(pow_fun, &[base.into(), exp.into()], "call_int_pow")
        .try_as_basic_value()
@ -60,6 +75,7 @@ pub fn integer_power<'ctx, 'a>(
 }

 pub fn calculate_len_for_slice_range<'ctx, 'a>(
+    generator: &mut dyn CodeGenerator,
    ctx: &mut CodeGenContext<'ctx, 'a>,
    start: IntValue<'ctx>,
    end: IntValue<'ctx>,
@ -72,7 +88,21 @@ pub fn calculate_len_for_slice_range<'ctx, 'a>(
        ctx.module.add_function(SYMBOL, fn_t, None)
    });

-    // TODO: assert step != 0, throw exception if not
+    // assert step != 0, throw exception if not
+    let not_zero = ctx.builder.build_int_compare(
+        IntPredicate::NE,
+        step,
+        step.get_type().const_zero(),
+        "range_step_ne",
+    );
+    ctx.make_assert(
+        generator,
+        not_zero,
+        "0:ValueError",
+        "step must not be zero",
+        [None, None, None],
+        ctx.current_loc,
+    );
    ctx.builder
        .build_call(len_func, &[start.into(), end.into(), step.into()], "calc_len")
        .try_as_basic_value()
@ -129,7 +159,6 @@ pub fn handle_slice_indices<'a, 'ctx, G: CodeGenerator>(
    generator: &mut G,
    list: PointerValue<'ctx>,
 ) -> Result<(IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>), String> {
-    // TODO: throw exception when step is 0
    let int32 = ctx.ctx.i32_type();
    let zero = int32.const_zero();
    let one = int32.const_int(1, false);
@ -156,6 +185,21 @@ pub fn handle_slice_indices<'a, 'ctx, G: CodeGenerator>(
                .unwrap()
                .to_basic_value_enum(ctx, generator)?
                .into_int_value();
+            // assert step != 0, throw exception if not
+            let not_zero = ctx.builder.build_int_compare(
+                IntPredicate::NE,
+                step,
+                step.get_type().const_zero(),
+                "range_step_ne",
+            );
+            ctx.make_assert(
+                generator,
+                not_zero,
+                "0:ValueError",
+                "slice step cannot be zero",
+                [None, None, None],
+                ctx.current_loc,
+            );
            let len_id = ctx.builder.build_int_sub(length, one, "lenmin1");
            let neg = ctx.builder.build_int_compare(IntPredicate::SLT, step, zero, "step_is_neg");
            (
@ -231,14 +275,15 @@ pub fn handle_slice_index_bound<'a, 'ctx, G: CodeGenerator>(
 /// Order of tuples assign_idx and value_idx is ('start', 'end', 'step').
 /// Negative index should be handled before entering this function
 pub fn list_slice_assignment<'ctx, 'a>(
+    generator: &mut dyn CodeGenerator,
    ctx: &mut CodeGenContext<'ctx, 'a>,
-    size_ty: IntType<'ctx>,
    ty: BasicTypeEnum<'ctx>,
    dest_arr: PointerValue<'ctx>,
    dest_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
    src_arr: PointerValue<'ctx>,
    src_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
 ) {
+    let size_ty = generator.get_size_type(ctx.ctx);
    let int8_ptr = ctx.ctx.i8_type().ptr_type(AddressSpace::Generic);
    let int32 = ctx.ctx.i32_type();
    let (fun_symbol, elem_ptr_type) = ("__nac3_list_slice_assign_var_size", int8_ptr);
@ -282,8 +327,67 @@ pub fn list_slice_assignment<'ctx, 'a>(
    let src_len = ctx.builder.build_int_truncate_or_bit_cast(src_len, int32, "srclen32");

    // index in bound and positive should be done
-    // TODO: assert if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest), and
+    // assert if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest), and
    // throw exception if not satisfied
+    let src_end = ctx.builder
+        .build_select(
+            ctx.builder.build_int_compare(
+                inkwell::IntPredicate::SLT,
+                src_idx.2,
+                zero,
+                "is_neg",
+            ),
+            ctx.builder.build_int_sub(src_idx.1, one, "e_min_one"),
+            ctx.builder.build_int_add(src_idx.1, one, "e_add_one"),
+            "final_e",
+        )
+        .into_int_value();
+    let dest_end = ctx.builder
+        .build_select(
+            ctx.builder.build_int_compare(
+                inkwell::IntPredicate::SLT,
+                dest_idx.2,
+                zero,
+                "is_neg",
+            ),
+            ctx.builder.build_int_sub(dest_idx.1, one, "e_min_one"),
+            ctx.builder.build_int_add(dest_idx.1, one, "e_add_one"),
+            "final_e",
+        )
+        .into_int_value();
+    let src_slice_len =
+        calculate_len_for_slice_range(generator, ctx, src_idx.0, src_end, src_idx.2);
+    let dest_slice_len =
+        calculate_len_for_slice_range(generator, ctx, dest_idx.0, dest_end, dest_idx.2);
+    let src_eq_dest = ctx.builder.build_int_compare(
+        IntPredicate::EQ,
+        src_slice_len,
+        dest_slice_len,
+        "slice_src_eq_dest",
+    );
+    let src_slt_dest = ctx.builder.build_int_compare(
+        IntPredicate::SLT,
+        src_slice_len,
+        dest_slice_len,
+        "slice_src_slt_dest",
+    );
+    let dest_step_eq_one = ctx.builder.build_int_compare(
+        IntPredicate::EQ,
+        dest_idx.2,
+        dest_idx.2.get_type().const_int(1, false),
+        "slice_dest_step_eq_one",
+    );
+    let cond_1 = ctx.builder.build_and(dest_step_eq_one, src_slt_dest, "slice_cond_1");
+    let cond = ctx.builder.build_or(src_eq_dest, cond_1, "slice_cond");
+    ctx.make_assert(
+        generator,
+        cond,
+        "0:ValueError",
+        "attempt to assign sequence of size {0} to slice of size {1} with step size {2}",
+        [Some(src_slice_len), Some(dest_slice_len), Some(dest_idx.2)],
+        ctx.current_loc,
+    );
+
    let new_len = {
        let args = vec![
            dest_idx.0.into(),   // dest start idx
--- a/nac3core/src/codegen/mod.rs
+++ b/nac3core/src/codegen/mod.rs
@ -20,7 +20,7 @@ use inkwell::{
    values::{BasicValueEnum, FunctionValue, PhiValue, PointerValue}
 };
 use itertools::Itertools;
-use nac3parser::ast::{Stmt, StrRef};
+use nac3parser::ast::{Stmt, StrRef, Location};
 use parking_lot::{Condvar, Mutex};
 use std::collections::{HashMap, HashSet};
 use std::sync::{
@ -77,6 +77,7 @@ pub struct CodeGenContext<'ctx, 'a> {
    pub outer_catch_clauses:
        Option<(Vec<Option<BasicValueEnum<'ctx>>>, BasicBlock<'ctx>, PhiValue<'ctx>)>,
    pub need_sret: bool,
+    pub current_loc: Location,
 }

 impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
@ -259,6 +260,7 @@ fn get_llvm_type<'ctx>(
    unifier: &mut Unifier,
    top_level: &TopLevelContext,
    type_cache: &mut HashMap<Type, BasicTypeEnum<'ctx>>,
+    primitives: &PrimitiveStore,
    ty: Type,
 ) -> BasicTypeEnum<'ctx> {
    use TypeEnum::*;
@ -268,9 +270,28 @@ fn get_llvm_type<'ctx>(
        let ty_enum = unifier.get_ty(ty);
        let result = match &*ty_enum {
            TObj { obj_id, fields, .. } => {
-                // check to avoid treating primitives as classes
-                if obj_id.0 <= 7 {
-                    unreachable!();
+                // check to avoid treating primitives other than Option as classes
+                if obj_id.0 <= 10 {
+                    match (unifier.get_ty(ty).as_ref(), unifier.get_ty(primitives.option).as_ref())
+                    {
+                        (
+                            TypeEnum::TObj { obj_id, params, .. },
+                            TypeEnum::TObj { obj_id: opt_id, .. },
+                        ) if *obj_id == *opt_id => {
+                            return get_llvm_type(
+                                ctx,
+                                generator,
+                                unifier,
+                                top_level,
+                                type_cache,
+                                primitives,
+                                *params.iter().next().unwrap().1,
+                            )
+                            .ptr_type(AddressSpace::Generic)
+                            .into();
+                        }
+                        _ => unreachable!("must be option type"),
+                    }
                }
                // a struct with fields in the order of declaration
                let top_level_defs = top_level.definitions.read();
@ -289,6 +310,7 @@ fn get_llvm_type<'ctx>(
                                unifier,
                                top_level,
                                type_cache,
+                                primitives,
                                fields[&f.0].0,
                            )
                        })
@ -304,14 +326,14 @@ fn get_llvm_type<'ctx>(
                // a struct with fields in the order present in the tuple
                let fields = ty
                    .iter()
-                    .map(|ty| get_llvm_type(ctx, generator, unifier, top_level, type_cache, *ty))
+                    .map(|ty| get_llvm_type(ctx, generator, unifier, top_level, type_cache, primitives, *ty))
                    .collect_vec();
                ctx.struct_type(&fields, false).into()
            }
            TList { ty } => {
                // a struct with an integer and a pointer to an array
                let element_type =
-                    get_llvm_type(ctx, generator, unifier, top_level, type_cache, *ty);
+                    get_llvm_type(ctx, generator, unifier, top_level, type_cache, primitives, *ty);
                let fields = [
                    element_type.ptr_type(AddressSpace::Generic).into(),
                    generator.get_size_type(ctx).into(),
@ -339,13 +361,14 @@ fn need_sret<'ctx>(ctx: &'ctx Context, ty: BasicTypeEnum<'ctx>) -> bool {
    need_sret_impl(ctx, ty, true)
 }

-pub fn gen_func<'ctx, G: CodeGenerator>(
+pub fn gen_func_impl<'ctx, G: CodeGenerator, F: FnOnce(&mut G, &mut CodeGenContext) -> Result<(), String>> (
    context: &'ctx Context,
    generator: &mut G,
    registry: &WorkerRegistry,
    builder: Builder<'ctx>,
    module: Module<'ctx>,
    task: CodeGenTask,
+    codegen_function: F
 ) -> Result<(Builder<'ctx>, Module<'ctx>, FunctionValue<'ctx>), (Builder<'ctx>, String)> {
    let top_level_ctx = registry.top_level_ctx.clone();
    let static_value_store = registry.static_value_store.clone();
@ -385,6 +408,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
        range: unifier.get_representative(primitives.range),
        str: unifier.get_representative(primitives.str),
        exception: unifier.get_representative(primitives.exception),
+        option: unifier.get_representative(primitives.option),
    };

    let mut type_cache: HashMap<_, _> = [
@ -417,6 +441,8 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
        exception.set_body(&fields, false);
        exception.ptr_type(AddressSpace::Generic).into()
    });
+    // NOTE: special handling of option cannot use this type cache since it contains type var,
+    // handled inside get_llvm_type instead

    let (args, ret) = if let ConcreteTypeEnum::TFunc { args, ret, .. } =
        task.store.get(task.signature)
@ -437,7 +463,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
    let ret_type = if unifier.unioned(ret, primitives.none) {
        None
    } else {
-        Some(get_llvm_type(context, generator, &mut unifier, top_level_ctx.as_ref(), &mut type_cache, ret))
+        Some(get_llvm_type(context, generator, &mut unifier, top_level_ctx.as_ref(), &mut type_cache, &primitives, ret))
    };

    let has_sret = ret_type.map_or(false, |ty| need_sret(context, ty));
@ -450,6 +476,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
                &mut unifier,
                top_level_ctx.as_ref(),
                &mut type_cache,
+                &primitives,
                arg.ty,
            )
            .into()
@ -497,6 +524,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
                &mut unifier,
                top_level_ctx.as_ref(),
                &mut type_cache,
+                &primitives,
                arg.ty,
            ),
            &arg.name.to_string(),
@ -543,28 +571,38 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
        module,
        unifier,
        static_value_store,
-        need_sret: has_sret
+        need_sret: has_sret,
+        current_loc: Default::default(),
    };

-    let mut err = None;
-    for stmt in task.body.iter() {
-        if let Err(e) = generator.gen_stmt(&mut code_gen_context, stmt) {
-            err = Some(e);
-            break;
-        }
-        if code_gen_context.is_terminated() {
-            break;
-        }
-    }
+    let result = codegen_function(generator, &mut code_gen_context);
+
    // after static analysis, only void functions can have no return at the end.
    if !code_gen_context.is_terminated() {
        code_gen_context.builder.build_return(None);
    }

    let CodeGenContext { builder, module, .. } = code_gen_context;
-    if let Some(e) = err {
+    if let Err(e) = result {
        return Err((builder, e));
    }

    Ok((builder, module, fn_val))
 }
+
+pub fn gen_func<'ctx, G: CodeGenerator>(
+    context: &'ctx Context,
+    generator: &mut G,
+    registry: &WorkerRegistry,
+    builder: Builder<'ctx>,
+    module: Module<'ctx>,
+    task: CodeGenTask,
+) -> Result<(Builder<'ctx>, Module<'ctx>, FunctionValue<'ctx>), (Builder<'ctx>, String)> {
+    let body = task.body.clone();
+    gen_func_impl(context, generator, registry, builder, module, task, |generator, ctx| {
+        for stmt in body.iter() {
+            generator.gen_stmt(ctx, stmt)?;
+        }
+        Ok(())
+    })
+}
--- a/nac3core/src/codegen/stmt.rs
+++ b/nac3core/src/codegen/stmt.rs
@ -134,8 +134,8 @@ pub fn gen_assign<'ctx, 'a, G: CodeGenerator>(
                    };
                let src_ind = handle_slice_indices(&None, &None, &None, ctx, generator, value)?;
                list_slice_assignment(
+                    generator,
                    ctx,
-                    generator.get_size_type(ctx.ctx),
                    ty,
                    ls,
                    (start, end, step),
@ -189,7 +189,8 @@ pub fn gen_for<'ctx, 'a, G: CodeGenerator>(
        if ctx.unifier.unioned(iter.custom.unwrap(), ctx.primitives.range) {
            // setup
            let iter_val = iter_val.into_pointer_value();
-            let i = generator.gen_store_target(ctx, target)?;
+            let i = generator.gen_var_alloc(ctx, int32.into())?;
+            let user_i = generator.gen_store_target(ctx, target)?;
            let (start, end, step) = destructure_range(ctx, iter_val);
            ctx.builder.build_store(i, ctx.builder.build_int_sub(start, step, "start_init"));
            ctx.builder.build_unconditional_branch(test_bb);
@ -207,6 +208,7 @@ pub fn gen_for<'ctx, 'a, G: CodeGenerator>(
                "start_loop",
            );
            ctx.builder.build_store(i, tmp);
+            ctx.builder.build_store(user_i, tmp);
            // // if step > 0, continue when i < end
            let cmp1 = ctx.builder.build_int_compare(inkwell::IntPredicate::SLT, tmp, end, "cmp1");
            // if step < 0, continue when i > end
@ -420,8 +422,8 @@ pub fn final_proxy<'ctx, 'a>(
    final_paths.push(block);
 }

-pub fn get_builtins<'ctx, 'a, G: CodeGenerator>(
-    generator: &mut G,
+pub fn get_builtins<'ctx, 'a>(
+    generator: &mut dyn CodeGenerator,
    ctx: &mut CodeGenContext<'ctx, 'a>,
    symbol: &str,
 ) -> FunctionValue<'ctx> {
@ -517,8 +519,8 @@ pub fn exn_constructor<'ctx, 'a>(
    Ok(Some(zelf.into()))
 }

-pub fn gen_raise<'ctx, 'a, G: CodeGenerator>(
-    generator: &mut G,
+pub fn gen_raise<'ctx, 'a>(
+    generator: &mut dyn CodeGenerator,
    ctx: &mut CodeGenContext<'ctx, 'a>,
    exception: Option<&BasicValueEnum<'ctx>>,
    loc: Location,
@ -929,6 +931,7 @@ pub fn gen_stmt<'ctx, 'a, G: CodeGenerator>(
    ctx: &mut CodeGenContext<'ctx, 'a>,
    stmt: &Stmt<Option<Type>>,
 ) -> Result<(), String> {
+    ctx.current_loc = stmt.location;
    match &stmt.node {
        StmtKind::Pass { .. } => {}
        StmtKind::Expr { value, .. } => {
@ -973,7 +976,25 @@ pub fn gen_stmt<'ctx, 'a, G: CodeGenerator>(
                gen_raise(generator, ctx, None, stmt.location);
            }
        }
-        _ => unimplemented!(),
+        StmtKind::Assert { test, msg, .. } => {
+            let test =
+                generator.gen_expr(ctx, test)?.unwrap().to_basic_value_enum(ctx, generator)?;
+            let err_msg = match msg {
+                Some(msg) => {
+                    generator.gen_expr(ctx, msg)?.unwrap().to_basic_value_enum(ctx, generator)?
+                }
+                None => ctx.gen_string(generator, ""),
+            };
+            ctx.make_assert_impl(
+                generator,
+                test.into_int_value(),
+                "0:AssertionError",
+                err_msg,
+                [None, None, None],
+                stmt.location,
+            )
+        }
+        _ => unimplemented!()
    };
    Ok(())
 }
--- a/nac3core/src/codegen/test.rs
+++ b/nac3core/src/codegen/test.rs
@ -71,7 +71,7 @@ impl SymbolResolver for Resolver {
        unimplemented!()
    }

-    fn get_exception_id(&self, tyid: usize) -> usize {
+    fn get_exception_id(&self, _tyid: usize) -> usize {
        unimplemented!()
    }
 }
@ -180,13 +180,22 @@ fn test_primitives() {
        let expected = indoc! {"
            ; ModuleID = 'test'
            source_filename = \"test\"
-
+            
            define i32 @testing(i32 %0, i32 %1) {
            init:
              %add = add i32 %0, %1
              %cmp = icmp eq i32 %add, 1
-              %ifexpr = select i1 %cmp, i32 %0, i32 0
-              ret i32 %ifexpr
+              br i1 %cmp, label %then, label %else
+            
+            then:                                             ; preds = %init
+              br label %cont
+            
+            else:                                             ; preds = %init
+              br label %cont
+            
+            cont:                                             ; preds = %else, %then
+              %if_exp_result.0 = phi i32 [ %0, %then ], [ 0, %else ]
+              ret i32 %if_exp_result.0
            }
       "}
        .trim();
--- a/nac3core/src/symbol_resolver.rs
+++ b/nac3core/src/symbol_resolver.rs
@ -14,7 +14,7 @@ use crate::{
        typedef::{Type, Unifier},
    },
 };
-use inkwell::values::{BasicValueEnum, FloatValue, IntValue, PointerValue};
+use inkwell::values::{BasicValueEnum, FloatValue, IntValue, PointerValue, StructValue};
 use itertools::{chain, izip};
 use nac3parser::ast::{Expr, Location, StrRef};
 use parking_lot::RwLock;
@ -29,6 +29,8 @@ pub enum SymbolValue {
    Double(f64),
    Bool(bool),
    Tuple(Vec<SymbolValue>),
+    OptionSome(Box<SymbolValue>),
+    OptionNone,
 }

 impl Display for SymbolValue {
@ -50,6 +52,8 @@ impl Display for SymbolValue {
            SymbolValue::Tuple(t) => {
                write!(f, "({})", t.iter().map(|v| format!("{}", v)).collect::<Vec<_>>().join(", "))
            }
+            SymbolValue::OptionSome(v) => write!(f, "Some({})", v),
+            SymbolValue::OptionNone => write!(f, "none"),
        }
    }
 }
@ -106,6 +110,12 @@ impl<'ctx> From<FloatValue<'ctx>> for ValueEnum<'ctx> {
    }
 }

+impl<'ctx> From<StructValue<'ctx>> for ValueEnum<'ctx> {
+    fn from(v: StructValue<'ctx>) -> Self {
+        ValueEnum::Dynamic(v.into())
+    }
+}
+
 impl<'ctx> ValueEnum<'ctx> {
    pub fn to_basic_value_enum<'a>(
        self,
@ -153,12 +163,11 @@ pub trait SymbolResolver {
 }

 thread_local! {
-    static IDENTIFIER_ID: [StrRef; 12] = [
+    static IDENTIFIER_ID: [StrRef; 11] = [
        "int32".into(),
        "int64".into(),
        "float".into(),
        "bool".into(),
-        "None".into(),
        "virtual".into(),
        "list".into(),
        "tuple".into(),
@ -183,14 +192,13 @@ pub fn parse_type_annotation<T>(
    let int64_id = ids[1];
    let float_id = ids[2];
    let bool_id = ids[3];
-    let none_id = ids[4];
-    let virtual_id = ids[5];
-    let list_id = ids[6];
-    let tuple_id = ids[7];
-    let str_id = ids[8];
-    let exn_id = ids[9];
-    let uint32_id = ids[10];
-    let uint64_id = ids[11];
+    let virtual_id = ids[4];
+    let list_id = ids[5];
+    let tuple_id = ids[6];
+    let str_id = ids[7];
+    let exn_id = ids[8];
+    let uint32_id = ids[9];
+    let uint64_id = ids[10];

    let name_handling = |id: &StrRef, loc: Location, unifier: &mut Unifier| {
        if *id == int32_id {
@ -205,8 +213,6 @@ pub fn parse_type_annotation<T>(
            Ok(primitives.float)
        } else if *id == bool_id {
            Ok(primitives.bool)
-        } else if *id == none_id {
-            Ok(primitives.none)
        } else if *id == str_id {
            Ok(primitives.str)
        } else if *id == exn_id {
--- a/nac3core/src/toplevel/builtins.rs
+++ b/nac3core/src/toplevel/builtins.rs
@ -105,6 +105,20 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
        ("__param2__".into(), int64, true),
    ];

+    // for Option, is_some and is_none share the same type: () -> bool,
+    // and they are methods under the same class `Option`
+    let (is_some_ty, unwrap_ty, (option_ty_var, option_ty_var_id)) =
+        if let TypeEnum::TObj { fields, params, .. } =
+            primitives.1.get_ty(primitives.0.option).as_ref()
+        {
+            (
+                *fields.get(&"is_some".into()).unwrap(),
+                *fields.get(&"unwrap".into()).unwrap(),
+                (*params.iter().next().unwrap().1, *params.iter().next().unwrap().0),
+            )
+        } else {
+            unreachable!()
+        };
    let top_level_def_list = vec![
        Arc::new(RwLock::new(TopLevelComposer::make_top_level_class_def(
            0,
@ -180,6 +194,94 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
            None,
            None,
        ))),
+        Arc::new(RwLock::new({
+            TopLevelDef::Class {
+                name: "Option".into(),
+                object_id: DefinitionId(10),
+                type_vars: vec![option_ty_var],
+                fields: vec![],
+                methods: vec![
+                    ("is_some".into(), is_some_ty.0, DefinitionId(11)),
+                    ("is_none".into(), is_some_ty.0, DefinitionId(12)),
+                    ("unwrap".into(), unwrap_ty.0, DefinitionId(13)),
+                ],
+                ancestors: vec![TypeAnnotation::CustomClass {
+                    id: DefinitionId(10),
+                    params: Default::default(),
+                }],
+                constructor: None,
+                resolver: None,
+                loc: None,
+            }
+        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Option.is_some".into(),
+            simple_name: "is_some".into(),
+            signature: is_some_ty.0,
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, obj, _, _, generator| {
+                    let obj_val = obj.unwrap().1.clone().to_basic_value_enum(ctx, generator)?;
+                    if let BasicValueEnum::PointerValue(ptr) = obj_val {
+                        Ok(Some(ctx.builder.build_is_not_null(ptr, "is_some").into()))
+                    } else {
+                        unreachable!("option must be ptr")
+                    }
+                },
+            )))),
+            loc: None,
+        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Option.is_none".into(),
+            simple_name: "is_none".into(),
+            signature: is_some_ty.0,
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, obj, _, _, generator| {
+                    let obj_val = obj.unwrap().1.clone().to_basic_value_enum(ctx, generator)?;
+                    if let BasicValueEnum::PointerValue(ptr) = obj_val {
+                        Ok(Some(ctx.builder.build_is_null(ptr, "is_none").into()))
+                    } else {
+                        unreachable!("option must be ptr")
+                    }
+                },
+            )))),
+            loc: None,
+        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Option.unwrap".into(),
+            simple_name: "unwrap".into(),
+            signature: unwrap_ty.0,
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, obj, _, _, generator| {
+                    if let BasicValueEnum::PointerValue(ptr) = obj.unwrap().1.to_basic_value_enum(ctx, generator)? {
+                        let not_null = ctx.builder.build_is_not_null(ptr, "unwrap_not_null");
+                        ctx.make_assert(
+                            generator,
+                            not_null,
+                            "0:UnwrapNoneError",
+                            "",
+                            [None, None, None],
+                            ctx.current_loc,
+                        );
+                        Ok(Some(ctx.builder.build_load(ptr, "unwrap_some")))
+                    } else {
+                        unreachable!("option must be ptr")
+                    }
+                },
+            )))),
+            loc: None,
+        })),
        Arc::new(RwLock::new(TopLevelDef::Function {
            name: "int32".into(),
            simple_name: "int32".into(),
@ -581,8 +683,28 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
                            step = Some(arg.1.clone().to_basic_value_enum(ctx, generator)?);
                        }
                    }
-                    // TODO: error when step == 0
-                    let step = step.unwrap_or_else(|| int32.const_int(1, false).into());
+                    let step = match step {
+                        Some(step) => {
+                            let step = step.into_int_value();
+                            // assert step != 0, throw exception if not
+                            let not_zero = ctx.builder.build_int_compare(
+                                IntPredicate::NE,
+                                step,
+                                step.get_type().const_zero(),
+                                "range_step_ne",
+                            );
+                            ctx.make_assert(
+                                generator,
+                                not_zero,
+                                "0:ValueError",
+                                "range() step must not be zero",
+                                [None, None, None],
+                                ctx.current_loc,
+                            );
+                            step
+                        }
+                        None => int32.const_int(1, false),
+                    };
                    let stop = stop.unwrap_or_else(|| {
                        let v = start.unwrap();
                        start = None;
@ -884,7 +1006,7 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
                        Ok(if ctx.unifier.unioned(arg_ty, range_ty) {
                            let arg = arg.into_pointer_value();
                            let (start, end, step) = destructure_range(ctx, arg);
-                            Some(calculate_len_for_slice_range(ctx, start, end, step).into())
+                            Some(calculate_len_for_slice_range(generator, ctx, start, end, step).into())
                        } else {
                            let int32 = ctx.ctx.i32_type();
                            let zero = int32.const_zero();
@ -1098,6 +1220,28 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
            )))),
            loc: None,
        })),
+        Arc::new(RwLock::new(TopLevelDef::Function {
+            name: "Some".into(),
+            simple_name: "Some".into(),
+            signature: primitives.1.add_ty(TypeEnum::TFunc(FunSignature {
+                args: vec![FuncArg { name: "n".into(), ty: option_ty_var, default_value: None }],
+                ret: primitives.0.option,
+                vars: HashMap::from([(option_ty_var_id, option_ty_var)]),
+            })),
+            var_id: vec![option_ty_var_id],
+            instance_to_symbol: Default::default(),
+            instance_to_stmt: Default::default(),
+            resolver: None,
+            codegen_callback: Some(Arc::new(GenCall::new(Box::new(
+                |ctx, _, _fun, args, generator| {
+                    let arg_val = args[0].1.clone().to_basic_value_enum(ctx, generator)?;
+                    let alloca = ctx.builder.build_alloca(arg_val.get_type(), "alloca_some");
+                    ctx.builder.build_store(alloca, arg_val);
+                    Ok(Some(alloca.into()))
+                },
+            )))),
+            loc: None,
+        })),
    ];

    let ast_list: Vec<Option<ast::Stmt<()>>> =
@ -1123,6 +1267,7 @@ pub fn get_builtins(primitives: &mut (PrimitiveStore, Unifier)) -> BuiltinInfo {
            "min",
            "max",
            "abs",
+            "Some",
        ],
    )
 }
--- a/nac3core/src/toplevel/composer.rs
+++ b/nac3core/src/toplevel/composer.rs
@ -74,6 +74,8 @@ impl TopLevelComposer {
            "self".into(),
            "Kernel".into(),
            "KernelInvariant".into(),
+            "Some".into(),
+            "Option".into(),
        ]);
        let defined_names: HashSet<String> = Default::default();
        let method_class: HashMap<DefinitionId, DefinitionId> = Default::default();
@ -89,10 +91,9 @@ impl TopLevelComposer {
                assert!(name == *simple_name);
                builtin_ty.insert(name, *signature);
                builtin_id.insert(name, DefinitionId(id));
-            } else if let TopLevelDef::Class { name, constructor, object_id, type_vars, .. } = &*def
+            } else if let TopLevelDef::Class { name, constructor, object_id, .. } = &*def
            {
                assert!(id == object_id.0);
-                assert!(type_vars.is_empty());
                if let Some(constructor) = constructor {
                    builtin_ty.insert(*name, *constructor);
                }
@ -1783,9 +1784,7 @@ impl TopLevelComposer {
                            })
                        };
                        let mut identifiers = {
-                            // NOTE: none and function args?
                            let mut result: HashSet<_> = HashSet::new();
-                            result.insert("None".into());
                            if self_type.is_some() {
                                result.insert("self".into());
                            }
@ -1808,9 +1807,7 @@ impl TopLevelComposer {
                            },
                            unifier,
                            variable_mapping: {
-                                // NOTE: none and function args?
                                let mut result: HashMap<StrRef, Type> = HashMap::new();
-                                result.insert("None".into(), primitives_ty.none);
                                if let Some(self_ty) = self_type {
                                    result.insert("self".into(), self_ty);
                                }
--- a/nac3core/src/toplevel/helper.rs
+++ b/nac3core/src/toplevel/helper.rs
@ -107,7 +107,43 @@ impl TopLevelComposer {
            fields: HashMap::new(),
            params: HashMap::new(),
        });
-        let primitives = PrimitiveStore { int32, int64, float, bool, none, range, str, exception, uint32, uint64 };
+
+        let option_type_var = unifier.get_fresh_var(Some("option_type_var".into()), None);
+        let is_some_type_fun_ty = unifier.add_ty(TypeEnum::TFunc(FunSignature {
+            args: vec![],
+            ret: bool,
+            vars: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        }));
+        let unwrap_fun_ty = unifier.add_ty(TypeEnum::TFunc(FunSignature {
+            args: vec![],
+            ret: option_type_var.0,
+            vars: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        }));
+        let option = unifier.add_ty(TypeEnum::TObj {
+            obj_id: DefinitionId(10),
+            fields: vec![
+                ("is_some".into(), (is_some_type_fun_ty, true)),
+                ("is_none".into(), (is_some_type_fun_ty, true)),
+                ("unwrap".into(), (unwrap_fun_ty, true)),
+            ]
+            .into_iter()
+            .collect::<HashMap<_, _>>(),
+            params: HashMap::from([(option_type_var.1, option_type_var.0)]),
+        });
+
+        let primitives = PrimitiveStore {
+            int32,
+            int64,
+            float,
+            bool,
+            none,
+            range,
+            str,
+            exception,
+            uint32,
+            uint64,
+            option,
+        };
        crate::typecheck::magic_methods::set_primitives_magic_methods(&primitives, &mut unifier);
        (primitives, unifier)
    }
@ -380,76 +416,77 @@ impl TopLevelComposer {
        primitive: &PrimitiveStore,
        unifier: &mut Unifier,
    ) -> Result<(), String> {
-        let res = match val {
-            SymbolValue::Bool(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.bool) {
-                    None
-                } else {
-                    Some("bool".to_string())
+        fn type_default_param(
+            val: &SymbolValue,
+            primitive: &PrimitiveStore,
+            unifier: &mut Unifier,
+        ) -> TypeAnnotation {
+            match val {
+                SymbolValue::Bool(..) => TypeAnnotation::Primitive(primitive.bool),
+                SymbolValue::Double(..) => TypeAnnotation::Primitive(primitive.float),
+                SymbolValue::I32(..) => TypeAnnotation::Primitive(primitive.int32),
+                SymbolValue::I64(..) => TypeAnnotation::Primitive(primitive.int64),
+                SymbolValue::U32(..) => TypeAnnotation::Primitive(primitive.uint32),
+                SymbolValue::U64(..) => TypeAnnotation::Primitive(primitive.uint64),
+                SymbolValue::Str(..) => TypeAnnotation::Primitive(primitive.str),
+                SymbolValue::Tuple(vs) => {
+                    let vs_tys = vs
+                        .iter()
+                        .map(|v| type_default_param(v, primitive, unifier))
+                        .collect::<Vec<_>>();
+                    TypeAnnotation::Tuple(vs_tys)
                }
-            }
-            SymbolValue::Double(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.float) {
-                    None
-                } else {
-                    Some("float".to_string())
-                }
-            }
-            SymbolValue::I32(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.int32) {
-                    None
-                } else {
-                    Some("int32".to_string())
-                }
-            }
-            SymbolValue::I64(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.int64) {
-                    None
-                } else {
-                    Some("int64".to_string())
-                }
-            }
-            SymbolValue::U32(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.uint32) {
-                    None
-                } else {
-                    Some("uint32".to_string())
-                }
-            }
-            SymbolValue::U64(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.uint64) {
-                    None
-                } else {
-                    Some("uint64".to_string())
-                }
-            }
-            SymbolValue::Str(..) => {
-                if matches!(ty, TypeAnnotation::Primitive(t) if *t == primitive.str) {
-                    None
-                } else {
-                    Some("str".to_string())
-                }
-            }
-            SymbolValue::Tuple(elts) => {
-                if let TypeAnnotation::Tuple(elts_ty) = ty {
-                    for (e, t) in elts.iter().zip(elts_ty.iter()) {
-                        Self::check_default_param_type(e, t, primitive, unifier)?
+                SymbolValue::OptionNone => TypeAnnotation::CustomClass {
+                    id: primitive.option.get_obj_id(unifier),
+                    params: Default::default(),
+                },
+                SymbolValue::OptionSome(v) => {
+                    let ty = type_default_param(v, primitive, unifier);
+                    TypeAnnotation::CustomClass {
+                        id: primitive.option.get_obj_id(unifier),
+                        params: vec![ty],
                    }
-                    if elts.len() != elts_ty.len() {
-                        Some(format!("tuple of length {}", elts.len()))
-                    } else {
-                        None
-                    }
-                } else {
-                    Some("tuple".to_string())
                }
            }
-        };
-        if let Some(found) = res {
+        }
+
+        fn is_compatible(
+            found: &TypeAnnotation,
+            expect: &TypeAnnotation,
+            unifier: &mut Unifier,
+            primitive: &PrimitiveStore,
+        ) -> bool {
+            match (found, expect) {
+                (TypeAnnotation::Primitive(f), TypeAnnotation::Primitive(e)) => {
+                    unifier.unioned(*f, *e)
+                }
+                (
+                    TypeAnnotation::CustomClass { id: f_id, params: f_param },
+                    TypeAnnotation::CustomClass { id: e_id, params: e_param },
+                ) => {
+                    *f_id == *e_id
+                        && *f_id == primitive.option.get_obj_id(unifier)
+                        && (f_param.is_empty()
+                            || (f_param.len() == 1
+                                && e_param.len() == 1
+                                && is_compatible(&f_param[0], &e_param[0], unifier, primitive)))
+                }
+                (TypeAnnotation::Tuple(f), TypeAnnotation::Tuple(e)) => {
+                    f.len() == e.len()
+                        && f.iter()
+                            .zip(e.iter())
+                            .all(|(f, e)| is_compatible(f, e, unifier, primitive))
+                }
+                _ => false,
+            }
+        }
+
+        let found = type_default_param(val, primitive, unifier);
+        if !is_compatible(&found, ty, unifier, primitive) {
            Err(format!(
                "incompatible default parameter type, expect {}, found {}",
                ty.stringify(unifier),
-                found
+                found.stringify(unifier),
            ))
        } else {
            Ok(())
@ -475,6 +512,10 @@ pub fn parse_parameter_default_value(
            Constant::Tuple(tuple) => Ok(SymbolValue::Tuple(
                tuple.iter().map(|x| handle_constant(x, loc)).collect::<Result<Vec<_>, _>>()?,
            )),
+            Constant::None => Err(format!(
+                "`None` is not supported, use `none` for option type instead ({})",
+                loc
+            )),
            _ => unimplemented!("this constant is not supported at {}", loc),
        }
    }
@ -512,6 +553,11 @@ pub fn parse_parameter_default_value(
                    }
                    _ => Err(format!("only allow constant integer here at {}", default.location))
                }
+                ast::ExprKind::Name { id, .. } if *id == "Some".into() => Ok(
+                    SymbolValue::OptionSome(
+                        Box::new(parse_parameter_default_value(&args[0], resolver)?)
+                    )
+                ),
                _ => Err(format!("unsupported default parameter at {}", default.location)),
            }
        }
@ -520,15 +566,20 @@ pub fn parse_parameter_default_value(
            .map(|x| parse_parameter_default_value(x, resolver))
            .collect::<Result<Vec<_>, _>>()?
        )),
+        ast::ExprKind::Name { id, .. } if id == &"none".into() => Ok(SymbolValue::OptionNone),
        ast::ExprKind::Name { id, .. } => {
            resolver.get_default_param_value(default).ok_or_else(
                || format!(
-                    "`{}` cannot be used as a default parameter at {} (not primitive type or tuple / not defined?)",
+                    "`{}` cannot be used as a default parameter at {} \
+                    (not primitive type, option or tuple / not defined?)",
                    id,
                    default.location
                )
            )
        }
-        _ => Err(format!("unsupported default parameter at {}", default.location))
+        _ => Err(format!(
+            "unsupported default parameter (not primitive type, option or tuple) at {}",
+            default.location
+        ))
    }
 }
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__generic_class.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__generic_class.snap
@ -5,10 +5,10 @@ expression: res_vec

 ---
 [
-    "Class {\nname: \"Generic_A\",\nancestors: [\"{class: Generic_A, params: [\\\"V\\\"]}\", \"{class: B, params: []}\"],\nfields: [\"aa\", \"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\"), (\"fun\", \"fn[[a:int32], V]\")],\ntype_vars: [\"V\"]\n}\n",
+    "Class {\nname: \"Generic_A\",\nancestors: [\"Generic_A[V]\", \"B\"],\nfields: [\"aa\", \"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\"), (\"fun\", \"fn[[a:int32], V]\")],\ntype_vars: [\"V\"]\n}\n",
    "Function {\nname: \"Generic_A.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
-    "Function {\nname: \"Generic_A.fun\",\nsig: \"fn[[a:int32], V]\",\nvar_id: [17]\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"{class: B, params: []}\"],\nfields: [\"aa\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\")],\ntype_vars: []\n}\n",
+    "Function {\nname: \"Generic_A.fun\",\nsig: \"fn[[a:int32], V]\",\nvar_id: [18]\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B\"],\nfields: [\"aa\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"B.foo\",\nsig: \"fn[[b:T], none]\",\nvar_id: []\n}\n",
 ]
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__inheritance_override.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__inheritance_override.snap
@ -5,13 +5,13 @@ expression: res_vec

 ---
 [
-    "Class {\nname: \"A\",\nancestors: [\"{class: A, params: [\\\"T\\\"]}\"],\nfields: [\"a\", \"b\", \"c\"],\nmethods: [(\"__init__\", \"fn[[t:T], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: [\"T\"]\n}\n",
+    "Class {\nname: \"A\",\nancestors: [\"A[T]\"],\nfields: [\"a\", \"b\", \"c\"],\nmethods: [(\"__init__\", \"fn[[t:T], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: [\"T\"]\n}\n",
    "Function {\nname: \"A.__init__\",\nsig: \"fn[[t:T], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"A.fun\",\nsig: \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\",\nvar_id: []\n}\n",
    "Function {\nname: \"A.foo\",\nsig: \"fn[[c:C], none]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"{class: B, params: [\\\"var6\\\"]}\", \"{class: A, params: [\\\"float\\\"]}\"],\nfields: [\"a\", \"b\", \"c\", \"d\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: [\"var6\"]\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B[var7]\", \"A[float]\"],\nfields: [\"a\", \"b\", \"c\", \"d\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: [\"var7\"]\n}\n",
    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"B.fun\",\nsig: \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"C\",\nancestors: [\"{class: C, params: []}\", \"{class: B, params: [\\\"bool\\\"]}\", \"{class: A, params: [\\\"float\\\"]}\"],\nfields: [\"a\", \"b\", \"c\", \"d\", \"e\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: []\n}\n",
+    "Class {\nname: \"C\",\nancestors: [\"C\", \"B[bool]\", \"A[float]\"],\nfields: [\"a\", \"b\", \"c\", \"d\", \"e\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:int32, b:T], list[virtual[B[bool]]]]\"), (\"foo\", \"fn[[c:C], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"C.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
 ]
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__list_tuple_generic.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__list_tuple_generic.snap
@ -6,10 +6,10 @@ expression: res_vec
 ---
 [
    "Function {\nname: \"foo\",\nsig: \"fn[[a:list[int32], b:tuple[T, float]], A[B, bool]]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"A\",\nancestors: [\"{class: A, params: [\\\"T\\\", \\\"V\\\"]}\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[v:V], none]\"), (\"fun\", \"fn[[a:T], V]\")],\ntype_vars: [\"T\", \"V\"]\n}\n",
-    "Function {\nname: \"A.__init__\",\nsig: \"fn[[v:V], none]\",\nvar_id: [19]\n}\n",
-    "Function {\nname: \"A.fun\",\nsig: \"fn[[a:T], V]\",\nvar_id: [24]\n}\n",
+    "Class {\nname: \"A\",\nancestors: [\"A[T, V]\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[v:V], none]\"), (\"fun\", \"fn[[a:T], V]\")],\ntype_vars: [\"T\", \"V\"]\n}\n",
+    "Function {\nname: \"A.__init__\",\nsig: \"fn[[v:V], none]\",\nvar_id: [20]\n}\n",
+    "Function {\nname: \"A.fun\",\nsig: \"fn[[a:T], V]\",\nvar_id: [25]\n}\n",
    "Function {\nname: \"gfun\",\nsig: \"fn[[a:A[int32, list[float]]], none]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"{class: B, params: []}\"],\nfields: [],\nmethods: [(\"__init__\", \"fn[[], none]\")],\ntype_vars: []\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B\"],\nfields: [],\nmethods: [(\"__init__\", \"fn[[], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
 ]
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__self1.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__self1.snap
@ -5,10 +5,10 @@ expression: res_vec

 ---
 [
-    "Class {\nname: \"A\",\nancestors: [\"{class: A, params: [\\\"var5\\\", \\\"var6\\\"]}\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[a:A[bool, float], b:B], none]\"), (\"fun\", \"fn[[a:A[bool, float]], A[bool, int32]]\")],\ntype_vars: [\"var5\", \"var6\"]\n}\n",
+    "Class {\nname: \"A\",\nancestors: [\"A[var6, var7]\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[a:A[bool, float], b:B], none]\"), (\"fun\", \"fn[[a:A[bool, float]], A[bool, int32]]\")],\ntype_vars: [\"var6\", \"var7\"]\n}\n",
    "Function {\nname: \"A.__init__\",\nsig: \"fn[[a:A[bool, float], b:B], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"A.fun\",\nsig: \"fn[[a:A[bool, float]], A[bool, int32]]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"{class: B, params: []}\", \"{class: A, params: [\\\"int64\\\", \\\"bool\\\"]}\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:A[bool, float]], A[bool, int32]]\"), (\"foo\", \"fn[[b:B], B]\"), (\"bar\", \"fn[[a:A[int32, list[B]]], tuple[A[bool, virtual[A[B, int32]]], B]]\")],\ntype_vars: []\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B\", \"A[int64, bool]\"],\nfields: [\"a\", \"b\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[a:A[bool, float]], A[bool, int32]]\"), (\"foo\", \"fn[[b:B], B]\"), (\"bar\", \"fn[[a:A[int32, list[B]]], tuple[A[bool, virtual[A[B, int32]]], B]]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"B.foo\",\nsig: \"fn[[b:B], B]\",\nvar_id: []\n}\n",
    "Function {\nname: \"B.bar\",\nsig: \"fn[[a:A[int32, list[B]]], tuple[A[bool, virtual[A[B, int32]]], B]]\",\nvar_id: []\n}\n",
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__simple_class_compose.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__simple_class_compose.snap
@ -1,19 +1,19 @@
 ---
 source: nac3core/src/toplevel/test.rs
-assertion_line: 540
+assertion_line: 549
 expression: res_vec

 ---
 [
-    "Class {\nname: \"A\",\nancestors: [\"{class: A, params: []}\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
+    "Class {\nname: \"A\",\nancestors: [\"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"A.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"A.fun\",\nsig: \"fn[[b:B], none]\",\nvar_id: []\n}\n",
-    "Function {\nname: \"A.foo\",\nsig: \"fn[[a:T, b:V], none]\",\nvar_id: [25]\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"{class: B, params: []}\", \"{class: C, params: []}\", \"{class: A, params: []}\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
+    "Function {\nname: \"A.foo\",\nsig: \"fn[[a:T, b:V], none]\",\nvar_id: [26]\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B\", \"C\", \"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
-    "Class {\nname: \"C\",\nancestors: [\"{class: C, params: []}\", \"{class: A, params: []}\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
+    "Class {\nname: \"C\",\nancestors: [\"C\", \"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
    "Function {\nname: \"C.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"C.fun\",\nsig: \"fn[[b:B], none]\",\nvar_id: []\n}\n",
    "Function {\nname: \"foo\",\nsig: \"fn[[a:A], none]\",\nvar_id: []\n}\n",
-    "Function {\nname: \"ff\",\nsig: \"fn[[a:T], V]\",\nvar_id: [33]\n}\n",
+    "Function {\nname: \"ff\",\nsig: \"fn[[a:T], V]\",\nvar_id: [34]\n}\n",
 ]
--- a/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__simple_pass_in_class.snap
+++ b/nac3core/src/toplevel/snapshots/nac3coretopleveltest__test_analyze__simple_pass_in_class.snap
@ -1,9 +1,9 @@
 ---
 source: nac3core/src/toplevel/test.rs
-assertion_line: 541
+assertion_line: 549
 expression: res_vec

 ---
 [
-    "Class {\nname: \"A\",\nancestors: [\"{class: A, params: []}\"],\nfields: [],\nmethods: [],\ntype_vars: []\n}\n",
+    "Class {\nname: \"A\",\nancestors: [\"A\"],\nfields: [],\nmethods: [],\ntype_vars: []\n}\n",
 ]
--- a/nac3core/src/toplevel/test.rs
+++ b/nac3core/src/toplevel/test.rs
@ -65,14 +65,14 @@ impl SymbolResolver for Resolver {
    }

    fn get_identifier_def(&self, id: StrRef) -> Result<DefinitionId, String> {
-        self.0.id_to_def.lock().get(&id).cloned().ok_or("Unknown identifier".to_string())
+        self.0.id_to_def.lock().get(&id).cloned().ok_or_else(|| "Unknown identifier".to_string())
    }

    fn get_string_id(&self, _: &str) -> i32 {
        unimplemented!()
    }

-    fn get_exception_id(&self, tyid: usize) -> usize {
+    fn get_exception_id(&self, _tyid: usize) -> usize {
        unimplemented!()
    }
 }
--- a/nac3core/src/toplevel/type_annotation.rs
+++ b/nac3core/src/toplevel/type_annotation.rs
@ -29,20 +29,28 @@ impl TypeAnnotation {
                        {
                            (*name).into()
                        } else {
-                            format!("def_{}", id.0)
+                            unreachable!()
                        }
                    }
-                    None => format!("def_{}", id.0),
+                    None => format!("class_def_{}", id.0),
                };
                format!(
-                    "{{class: {}, params: {:?}}}",
+                    "{}{}",
                    class_name,
-                    params.iter().map(|p| p.stringify(unifier)).collect_vec()
+                    {
+                        let param_list = params.iter().map(|p| p.stringify(unifier)).collect_vec().join(", ");
+                        if param_list.is_empty() {
+                            "".into()
+                        } else {
+                            format!("[{}]", param_list)
+                        }
+                    }
                )
            }
-            Virtual(ty) | List(ty) => ty.stringify(unifier),
+            Virtual(ty) => format!("virtual[{}]", ty.stringify(unifier)),
+            List(ty) => format!("list[{}]", ty.stringify(unifier)),
            Tuple(types) => {
-                format!("({:?})", types.iter().map(|p| p.stringify(unifier)).collect_vec())
+                format!("tuple[{}]", types.iter().map(|p| p.stringify(unifier)).collect_vec().join(", "))
            }
        }
    }
@ -72,8 +80,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
            Ok(TypeAnnotation::Primitive(primitives.float))
        } else if id == &"bool".into() {
            Ok(TypeAnnotation::Primitive(primitives.bool))
-        } else if id == &"None".into() {
-            Ok(TypeAnnotation::Primitive(primitives.none))
        } else if id == &"str".into() {
            Ok(TypeAnnotation::Primitive(primitives.str))
        } else if id == &"Exception".into() {
@ -223,6 +229,29 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
            Ok(TypeAnnotation::List(def_ann.into()))
        }

+        // option
+        ast::ExprKind::Subscript { value, slice, .. }
+            if {
+                matches!(&value.node, ast::ExprKind::Name { id, .. } if id == &"Option".into())
+            } =>
+        {
+            let def_ann = parse_ast_to_type_annotation_kinds(
+                resolver,
+                top_level_defs,
+                unifier,
+                primitives,
+                slice.as_ref(),
+                locked,
+            )?;
+            let id =
+                if let TypeEnum::TObj { obj_id, .. } = unifier.get_ty(primitives.option).as_ref() {
+                    *obj_id
+                } else {
+                    unreachable!()
+                };
+            Ok(TypeAnnotation::CustomClass { id, params: vec![def_ann] })
+        }
+
        // tuple
        ast::ExprKind::Subscript { value, slice, .. }
            if {
--- a/nac3core/src/typecheck/function_check.rs
+++ b/nac3core/src/typecheck/function_check.rs
@ -20,6 +20,8 @@ impl<'a> Inferencer<'a> {
        defined_identifiers: &mut HashSet<StrRef>,
    ) -> Result<(), String> {
        match &pattern.node {
+            ast::ExprKind::Name { id, .. } if id == &"none".into() =>
+                Err(format!("cannot assign to a `none` (at {})", pattern.location)),
            ExprKind::Name { id, .. } => {
                if !defined_identifiers.contains(id) {
                    defined_identifiers.insert(*id);
@ -70,6 +72,9 @@ impl<'a> Inferencer<'a> {
        }
        match &expr.node {
            ExprKind::Name { id, .. } => {
+                if id == &"none".into() {
+                    return Ok(());
+                }
                self.should_have_value(expr)?;
                if !defined_identifiers.contains(id) {
                    match self.function_data.resolver.get_symbol_type(
--- a/nac3core/src/typecheck/type_inferencer/mod.rs
+++ b/nac3core/src/typecheck/type_inferencer/mod.rs
@ -40,6 +40,7 @@ pub struct PrimitiveStore {
    pub range: Type,
    pub str: Type,
    pub exception: Type,
+    pub option: Type,
 }

 pub struct FunctionData {
@ -425,6 +426,13 @@ impl<'a> fold::Fold<()> for Inferencer<'a> {
                let res_ty = self.infer_bin_ops(stmt.location, target, op, value)?;
                self.unify(res_ty, target.custom.unwrap(), &stmt.location)?;
            }
+            ast::StmtKind::Assert { test, msg, .. } => {
+                self.unify(test.custom.unwrap(), self.primitives.bool, &test.location)?;
+                match msg {
+                    Some(m) => self.unify(m.custom.unwrap(), self.primitives.str, &m.location)?,
+                    None => ()
+                }
+            }
            _ => return report_error("Unsupported statement type", stmt.location),
        };
        Ok(stmt)
@ -448,25 +456,47 @@ impl<'a> fold::Fold<()> for Inferencer<'a> {
                Some(self.infer_constant(value, &expr.location)?)
            }
            ast::ExprKind::Name { id, .. } => {
-                if !self.defined_identifiers.contains(id) {
-                    match self.function_data.resolver.get_symbol_type(
-                        self.unifier,
-                        &self.top_level.definitions.read(),
-                        self.primitives,
-                        *id,
-                    ) {
-                        Ok(_) => {
-                            self.defined_identifiers.insert(*id);
-                        }
-                        Err(e) => {
-                            return report_error(
-                                &format!("type error at identifier `{}` ({})", id, e),
-                                expr.location,
-                            );
+                // the name `none` is special since it may have different types
+                if id == &"none".into() {
+                    if let TypeEnum::TObj { params, .. } =
+                        self.unifier.get_ty_immutable(self.primitives.option).as_ref()
+                    {
+                        let var_map = params
+                            .iter()
+                            .map(|(id_var, ty)| {
+                                if let TypeEnum::TVar { id, range, name, loc, .. } = &*self.unifier.get_ty(*ty) {
+                                    assert_eq!(*id, *id_var);
+                                    (*id, self.unifier.get_fresh_var_with_range(range, *name, *loc).0)
+                                } else {
+                                    unreachable!()
+                                }
+                            })
+                            .collect::<HashMap<_, _>>();
+                        Some(self.unifier.subst(self.primitives.option, &var_map).unwrap())
+                    } else {
+                        unreachable!("must be tobj")
+                    }
+                } else {
+                    if !self.defined_identifiers.contains(id) {
+                        match self.function_data.resolver.get_symbol_type(
+                            self.unifier,
+                            &self.top_level.definitions.read(),
+                            self.primitives,
+                            *id,
+                        ) {
+                            Ok(_) => {
+                                self.defined_identifiers.insert(*id);
+                            }
+                            Err(e) => {
+                                return report_error(
+                                    &format!("type error at identifier `{}` ({})", id, e),
+                                    expr.location,
+                                );
+                            }
                        }
                    }
+                    Some(self.infer_identifier(*id)?)
                }
-                Some(self.infer_identifier(*id)?)
            }
            ast::ExprKind::List { elts, .. } => Some(self.infer_list(elts)?),
            ast::ExprKind::Tuple { elts, .. } => Some(self.infer_tuple(elts)?),
@ -932,6 +962,8 @@ impl<'a> Inferencer<'a> {
                Ok(self.unifier.add_ty(TypeEnum::TTuple { ty: ty? }))
            }
            ast::Constant::Str(_) => Ok(self.primitives.str),
+            ast::Constant::None
+                => report_error("CPython `None` not supported (nac3 uses `none` instead)", *loc),
            _ => report_error("not supported", *loc),
        }
    }
--- a/nac3core/src/typecheck/type_inferencer/test.rs
+++ b/nac3core/src/typecheck/type_inferencer/test.rs
@ -44,14 +44,14 @@ impl SymbolResolver for Resolver {
    }

    fn get_identifier_def(&self, id: StrRef) -> Result<DefinitionId, String> {
-        self.id_to_def.get(&id).cloned().ok_or("Unknown identifier".to_string())
+        self.id_to_def.get(&id).cloned().ok_or_else(|| "Unknown identifier".to_string())
    }

    fn get_string_id(&self, _: &str) -> i32 {
        unimplemented!()
    }

-    fn get_exception_id(&self, tyid: usize) -> usize {
+    fn get_exception_id(&self, _tyid: usize) -> usize {
        unimplemented!()
    }
 }
@ -129,7 +129,24 @@ impl TestEnvironment {
            fields: HashMap::new(),
            params: HashMap::new(),
        });
-        let primitives = PrimitiveStore { int32, int64, float, bool, none, range, str, exception, uint32, uint64 };
+        let option = unifier.add_ty(TypeEnum::TObj {
+            obj_id: DefinitionId(10),
+            fields: HashMap::new(),
+            params: HashMap::new(),
+        });
+        let primitives = PrimitiveStore {
+            int32,
+            int64,
+            float,
+            bool,
+            none,
+            range,
+            str,
+            exception,
+            uint32,
+            uint64,
+            option,
+        };
        set_primitives_magic_methods(&primitives, &mut unifier);

        let id_to_name = [
@ -237,6 +254,11 @@ impl TestEnvironment {
            fields: HashMap::new(),
            params: HashMap::new(),
        });
+        let option = unifier.add_ty(TypeEnum::TObj {
+            obj_id: DefinitionId(10),
+            fields: HashMap::new(),
+            params: HashMap::new(),
+        });
        identifier_mapping.insert("None".into(), none);
        for (i, name) in ["int32", "int64", "float", "bool", "none", "range", "str", "Exception"]
            .iter()
@ -259,7 +281,19 @@ impl TestEnvironment {
        }
        let defs = 7;

-        let primitives = PrimitiveStore { int32, int64, float, bool, none, range, str, exception, uint32, uint64 };
+        let primitives = PrimitiveStore {
+            int32,
+            int64,
+            float,
+            bool,
+            none,
+            range,
+            str,
+            exception,
+            uint32,
+            uint64,
+            option,
+        };

        let (v0, id) = unifier.get_dummy_var();

--- a/nac3core/src/typecheck/typedef/mod.rs
+++ b/nac3core/src/typecheck/typedef/mod.rs
@ -54,6 +54,18 @@ pub enum RecordKey {
    Int(i32),
 }

+impl Type {
+    // a wrapper function for cleaner code so that we don't need to
+    // write this long pattern matching just to get the field `obj_id`
+    pub fn get_obj_id(self, unifier: &Unifier) -> DefinitionId {
+        if let TypeEnum::TObj { obj_id, .. } = unifier.get_ty_immutable(self).as_ref() {
+            *obj_id
+        } else {
+            unreachable!("expect a object type")
+        }
+    }
+}
+
 impl From<&RecordKey> for StrRef {
    fn from(r: &RecordKey) -> Self {
        match r {
--- a/nac3parser/src/parser.rs
+++ b/nac3parser/src/parser.rs
@ -121,7 +121,7 @@ mod tests {
    #[test]
    fn test_parse_lambda() {
        let source = "lambda x, y: x * y"; // lambda(x, y): x * y";
-        let parse_ast = parse_program(&source, Default::default()).unwrap();
+        let parse_ast = parse_program(source, Default::default()).unwrap();
        insta::assert_debug_snapshot!(parse_ast);
    }

@ -129,7 +129,7 @@ mod tests {
    fn test_parse_tuples() {
        let source = "a, b = 4, 5";

-        insta::assert_debug_snapshot!(parse_program(&source, Default::default()).unwrap());
+        insta::assert_debug_snapshot!(parse_program(source, Default::default()).unwrap());
    }

    #[test]
@ -140,7 +140,7 @@ class Foo(A, B):
  pass
 def method_with_default(self, arg='default'):
  pass";
-        insta::assert_debug_snapshot!(parse_program(&source, Default::default()).unwrap());
+        insta::assert_debug_snapshot!(parse_program(source, Default::default()).unwrap());
    }

    #[test]
@ -183,7 +183,7 @@ while i < 2: # nac3: 4
    # nac3: if1
    if 1: # nac3: if2
        3";
-        insta::assert_debug_snapshot!(parse_program(&source, Default::default()).unwrap());
+        insta::assert_debug_snapshot!(parse_program(source, Default::default()).unwrap());
    }
    
    #[test]
@ -196,7 +196,7 @@ while test: # nac3: while3
    # nac3: simple assign0 
    a = 3 # nac3: simple assign1
 ";
-        insta::assert_debug_snapshot!(parse_program(&source, Default::default()).unwrap());
+        insta::assert_debug_snapshot!(parse_program(source, Default::default()).unwrap());
    }

    #[test]
@ -215,7 +215,7 @@ if a: # nac3: small2
 for i in a: # nac3: for1
    pass
 ";
-        insta::assert_debug_snapshot!(parse_program(&source, Default::default()).unwrap());
+        insta::assert_debug_snapshot!(parse_program(source, Default::default()).unwrap());
    }

    #[test]
@ -224,6 +224,6 @@ for i in a: # nac3: for1
 if a: # nac3: something
 a = 3
 ";
-        assert!(parse_program(&source, Default::default()).is_err());
+        assert!(parse_program(source, Default::default()).is_err());
    }
 }
--- a/nac3standalone/demo/demo.rs
+++ b/nac3standalone/demo/demo.rs
@ -74,6 +74,11 @@ pub extern "C" fn __nac3_personality(_state: u32, _exception_object: u32, _conte
    unimplemented!();
 }

+#[no_mangle]
+pub extern "C" fn __nac3_raise(_state: u32, _exception_object: u32, _context: u32) -> u32 {
+    unimplemented!();
+}
+
 extern "C" {
    fn run() -> i32;
 }
--- a/nac3standalone/demo/interpret_demo.py
+++ b/nac3standalone/demo/interpret_demo.py
@ -8,6 +8,38 @@ import pathlib
 from numpy import int32, int64, uint32, uint64
 from typing import TypeVar, Generic

+T = TypeVar('T')
+class Option(Generic[T]):
+    _nac3_option: T
+
+    def __init__(self, v: T):
+        self._nac3_option = v
+
+    def is_none(self):
+        return self._nac3_option is None
+    
+    def is_some(self):
+        return not self.is_none()
+    
+    def unwrap(self):
+        return self._nac3_option
+
+    def __repr__(self) -> str:
+        if self.is_none():
+            return "none"
+        else:
+            return "Some({})".format(repr(self._nac3_option))
+    
+    def __str__(self) -> str:
+        if self.is_none():
+            return "none"
+        else:
+            return "Some({})".format(str(self._nac3_option))
+
+def Some(v: T) -> Option[T]:
+    return Option(v)
+
+none = Option(None)

 def patch(module):
    def output_asciiart(x):
@ -39,6 +71,9 @@ def patch(module):
    module.TypeVar = TypeVar
    module.Generic = Generic
    module.extern = extern
+    module.Option = Option
+    module.Some = Some
+    module.none = none


 def file_import(filename, prefix="file_import_"):
--- a/nac3standalone/demo/src/default_param.py
+++ b/nac3standalone/demo/src/default_param.py
@ -0,0 +1,43 @@
+@extern
+def output_int32(x: int32):
+    ...
+
+def f1(a: int32 = 4):
+    output_int32(a)
+
+def f2(a: int64 = int64(123)):
+    output_int32(int32(a))
+
+def f3(a: uint32 = uint32(234)):
+    output_int32(int32(a))
+
+def f4(a: tuple[int32, tuple[int32, int32], int64] = (4, (5, 6), int64(7))):
+    output_int32(a[0])
+    output_int32(a[1][0])
+    output_int32(a[1][1])
+    output_int32(int32(a[2]))
+
+def f5(a: float = 3.45):
+    output_int32(int32(a))
+
+def f6(a: Option[list[int32]] = none):
+    if a.is_none():
+        a = Some([11,22,33])
+        output_int32(a.unwrap()[2])
+
+def f7(a: Option[tuple[int32, int64]] = Some((3, int64(123)))):
+    if a.is_some():
+        a_unwrap = a.unwrap()
+        output_int32(a_unwrap[0])
+        output_int32(int32(a_unwrap[1]))
+
+
+def run() -> int32:
+    f1()
+    f2()
+    f3()
+    f4()
+    f5()
+    f6()
+    f7()
+    return 0
--- a/nac3standalone/demo/src/loop.py
+++ b/nac3standalone/demo/src/loop.py
@ -0,0 +1,9 @@
+@extern
+def output_int32(x: int32):
+    ...
+
+def run() -> int32:
+    for _ in range(10):
+        output_int32(_)
+        _ = 0
+    return 0
--- a/nac3standalone/demo/src/option.py
+++ b/nac3standalone/demo/src/option.py
@ -0,0 +1,40 @@
+@extern
+def output_int32(x: int32):
+    ...
+
+class A:
+    d: Option[int32]
+    e: Option[Option[int32]]
+    def __init__(self, a: Option[int32], b: Option[Option[int32]]):
+        self.d = a
+        self.e = b
+
+def run() -> int32:
+    a = Some(3)
+    if a.is_some():
+        d = a.unwrap()
+        output_int32(a.unwrap())
+        a = none
+        if a.is_none():
+            output_int32(d + 2)
+    else:
+        a = Some(5)
+        c = Some(6)
+        output_int32(a.unwrap() + c.unwrap())
+
+    f = Some(4.3)
+    output_int32(int32(f.unwrap()))
+
+    obj = A(Some(6), none)
+    output_int32(obj.d.unwrap())
+
+    obj2 = Some(A(Some(7), none))
+    output_int32(obj2.unwrap().d.unwrap())
+
+    obj3 = Some(A(Some(8), Some(none)))
+    if obj3.unwrap().e.unwrap().is_none():
+        obj3.unwrap().e = Some(Some(9))
+    output_int32(obj3.unwrap().d.unwrap())
+    output_int32(obj3.unwrap().e.unwrap().unwrap())
+
+    return 0
--- a/nac3standalone/demo/src/pow.py
+++ b/nac3standalone/demo/src/pow.py
@ -0,0 +1,26 @@
+@extern
+def output_float64(f: float):
+    ...
+
+
+def run() -> int32:
+    output_float64(float(3 ** 1))
+    output_float64(float(3 ** 0))
+    output_float64(float(3 ** 19))
+    output_float64(1.0 ** -100)
+    output_float64(1.0 ** -2)
+    output_float64(1.0 ** 0)
+    output_float64(1.0 ** 1)
+    output_float64(1.0 ** 100)
+    output_float64(3.0 ** 0)
+    output_float64(3.0 ** 1)
+    output_float64(3.0 ** 2)
+    output_float64(3.0 ** -1)
+    output_float64(3.0 ** -2)
+    output_float64(3.0 ** -32767)
+    output_float64(3.0 ** -3.0)
+    output_float64(3.0 ** -0.0)
+    output_float64(3.0 ** 0.0)
+    output_float64(4.0 ** 0.5)
+    output_float64(4.0 ** -0.5)
+    return 0
--- a/nac3standalone/demo/src/tuple.py
+++ b/nac3standalone/demo/src/tuple.py
@ -0,0 +1,29 @@
+@extern
+def output_int32_list(x: list[int32]):
+    ...
+
+@extern
+def output_int32(x: int32):
+    ...
+
+class A:
+    a: int32
+    b: bool
+    def __init__(self, a: int32, b: bool):
+        self.a = a
+        self.b = b
+
+def run() -> int32:
+    data = [0, 1, 2, 3]
+
+    t = [(d, d + d) for d in data]
+    for i in t:
+        tt = (Some(i[1]), i[0])
+        tl = ([i[0], i[1] + i[0]], i[1])
+        output_int32(tt[0].unwrap())
+        output_int32(tt[1])
+        output_int32(tl[0][0])
+        output_int32(tl[0][1])
+        output_int32(tl[1])
+    
+    return 0
--- a/nix/llvm/TLI-musl.patch
+++ b/nix/llvm/TLI-musl.patch
--- a/nix/llvm/default.nix
+++ b/nix/llvm/default.nix
--- a/nix/llvm/gnu-install-dirs.patch
+++ b/nix/llvm/gnu-install-dirs.patch
--- a/nix/llvm/llvm-future-riscv-abi.diff
+++ b/nix/llvm/llvm-future-riscv-abi.diff
--- a/nix/llvm/outputs.patch
+++ b/nix/llvm/outputs.patch
--- a/nix/windows/PKGBUILD
+++ b/nix/windows/PKGBUILD
@ -0,0 +1,26 @@
+pkgbase="mingw-w64-nac3artiq"
+pkgname="mingw-w64-x86_64-nac3artiq"
+pkgver=1.0
+pkgrel=1
+pkgdesc="New ARTIQ compiler 3"
+arch=("any")
+mingw_arch=("mingw64")
+url="https://m-labs.hk"
+license=("LGPL")
+source=("nac3artiq.pyd")
+noextract=("nac3artiq.pyd")
+sha256sums=("SKIP")
+depends=("mingw-w64-x86_64-python")
+
+prepare() {
+  true
+}
+
+build() {
+  true
+}
+
+package() {
+  mkdir -p $pkgdir/mingw64/lib/python3.9/site-packages
+  cp ${srcdir}/nac3artiq.pyd $pkgdir/mingw64/lib/python3.9/site-packages
+}
--- a/nix/windows/default.nix
+++ b/nix/windows/default.nix
@ -33,13 +33,14 @@ let
  };
 in rec {
  llvm-nac3 = pkgs.stdenvNoCC.mkDerivation rec {
-    name = "llvm-nac3-msys2";
+    pname = "llvm-nac3-msys2";
+    version = "13.0.1";
    src-llvm = pkgs.fetchurl {
-      url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.1/llvm-13.0.1.src.tar.xz";
+      url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/llvm-${version}.src.tar.xz";
      sha256 = "sha256-7GuA2Cw4SsrS3BkpA6bPLNuv+4ibhL+5janXHmMPyDQ=";
    };
    src-clang = pkgs.fetchurl {
-      url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.1/clang-13.0.1.src.tar.xz";
+      url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/clang-${version}.src.tar.xz";
      sha256 = "sha256-eHqeLZn1yHIKoXc+S+AJRhzTDTvUD90kWR5HNGfJF8k=";
    };
    buildInputs = [ pkgs.wineWowPackages.stable ];
@ -73,12 +74,13 @@ in rec {
      ''
      wine64 ninja install
      '';
+    dontFixup = true;
  };
  nac3artiq = pkgs.rustPlatform.buildRustPackage {
-    name = "nac3artiq";
-    src = ../.;
-    cargoLock = { lockFile = ../Cargo.lock; };
-    nativeBuildInputs = [ pkgs.wineWowPackages.stable pkgs.zip ];
+    name = "nac3artiq-msys2";
+    src = ../../.;
+    cargoLock = { lockFile = ../../Cargo.lock; };
+    nativeBuildInputs = [ pkgs.wineWowPackages.stable ];
    buildPhase =
      ''
      export HOME=`mktemp -d`
@ -90,10 +92,9 @@ in rec {
      '';
    installPhase =
      ''
-      mkdir -p $out $out/nix-support
-      ln -s target/release/nac3artiq.dll nac3artiq.pyd
-      zip $out/nac3artiq.zip nac3artiq.pyd
-      echo file binary-dist $out/nac3artiq.zip >> $out/nix-support/hydra-build-products
+      mkdir $out $out/nix-support
+      cp target/release/nac3artiq.dll $out/nac3artiq.pyd
+      echo file binary-dist $out/nac3artiq.pyd >> $out/nix-support/hydra-build-products
      '';
    checkPhase =
      ''
@ -101,6 +102,56 @@ in rec {
      '';
    dontFixup = true;
  };
+  nac3artiq-pkg = pkgs.stdenvNoCC.mkDerivation {
+    name = "nac3artiq-msys2-pkg";
+    nativeBuildInputs = [ pkgs.pacman pkgs.fakeroot pkgs.libarchive pkgs.zstd ];
+    src = nac3artiq;
+    phases = [ "buildPhase" "installPhase" ];
+    buildPhase =
+      ''
+      ln -s ${./PKGBUILD} PKGBUILD
+      ln -s $src/nac3artiq.pyd nac3artiq.pyd
+      makepkg --config ${./makepkg.conf} --nodeps
+      '';
+    installPhase =
+      ''
+      mkdir $out $out/nix-support
+      cp *.pkg.tar.zst $out
+      echo file msys2 $out/*.pkg.tar.zst >> $out/nix-support/hydra-build-products
+      '';
+  };
+  lld = pkgs.stdenvNoCC.mkDerivation rec {
+    pname = "lld-msys2";
+    version = "13.0.1";
+    src = pkgs.fetchurl {
+      url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/lld-${version}.src.tar.xz";
+      sha256 = "sha256-Zmr3Rei/e2gFM7TRi3ox3HyrV1sebk0mGSK7r9lkTPs=";
+    };
+    buildInputs = [ pkgs.wineWowPackages.stable ];
+    phases = [ "unpackPhase" "patchPhase" "configurePhase" "buildPhase" "installPhase" ];
+    patches = [ ./lld-disable-macho.diff ];
+    configurePhase =
+      ''
+      export HOME=`mktemp -d`
+      export WINEDEBUG=-all
+      export WINEPATH=Z:${msys2-env}/mingw64/bin\;Z:${llvm-nac3}/bin
+      ${silenceFontconfig}
+      mkdir build
+      cd build
+      wine64 cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=Z:$out
+      '';
+    buildPhase =
+      ''
+      wine64 ninja
+      '';
+    installPhase =
+      ''
+      mkdir -p $out $out/nix-support
+      cp bin/ld.lld.exe $out
+      echo file binary-dist $out/ld.lld.exe >> $out/nix-support/hydra-build-products
+      '';
+    dontFixup = true;
+  };
  wine-msys2 = pkgs.writeShellScriptBin "wine-msys2"
    ''
    export WINEDEBUG=-all
@ -108,4 +159,12 @@ in rec {
    export PYO3_CONFIG_FILE=Z:${pyo3-mingw-config}
    exec ${pkgs.wineWowPackages.stable}/bin/wine64 cmd
    '';
+  wine-msys2-build = pkgs.writeShellScriptBin "wine-msys2-build"
+    ''
+    export HOME=`mktemp -d`
+    export WINEDEBUG=-all
+    export WINEPATH=Z:${msys2-env}/mingw64/bin
+    ${silenceFontconfig}
+    exec ${pkgs.wineWowPackages.stable}/bin/wine64 $@
+    '';
 }
--- a/nix/windows/lld-disable-macho.diff
+++ b/nix/windows/lld-disable-macho.diff
@ -0,0 +1,36 @@
+diff '--color=auto' -Naur lld-13.0.1.src/CMakeLists.txt lld-13.0.1.src-new/CMakeLists.txt
+--- lld-13.0.1.src/CMakeLists.txt	2022-01-21 05:31:59.000000000 +0800
+++ lld-13.0.1.src-new/CMakeLists.txt	2022-03-27 18:26:30.284921982 +0800
+@@ -206,7 +206,6 @@
+ add_subdirectory(docs)
+ add_subdirectory(COFF)
+ add_subdirectory(ELF)
+-add_subdirectory(MachO)
+ add_subdirectory(MinGW)
+ add_subdirectory(wasm)
+ 
+diff '--color=auto' -Naur lld-13.0.1.src/tools/lld/CMakeLists.txt lld-13.0.1.src-new/tools/lld/CMakeLists.txt
+--- lld-13.0.1.src/tools/lld/CMakeLists.txt	2022-01-21 05:31:59.000000000 +0800
+++ lld-13.0.1.src-new/tools/lld/CMakeLists.txt	2022-03-27 18:26:40.805046295 +0800
+@@ -15,7 +15,6 @@
+   lldCOFF
+   lldDriver
+   lldELF
+-  lldMachO2
+   lldMinGW
+   lldWasm
+   )
+diff '--color=auto' -Naur lld-13.0.1.src/tools/lld/lld.cpp lld-13.0.1.src-new/tools/lld/lld.cpp
+--- lld-13.0.1.src/tools/lld/lld.cpp	2022-01-21 05:31:59.000000000 +0800
+++ lld-13.0.1.src-new/tools/lld/lld.cpp	2022-03-27 08:43:54.205524156 +0800
+@@ -148,10 +148,6 @@
+     return !elf::link(args, exitEarly, stdoutOS, stderrOS);
+   case WinLink:
+     return !coff::link(args, exitEarly, stdoutOS, stderrOS);
+-  case Darwin:
+-    return !macho::link(args, exitEarly, stdoutOS, stderrOS);
+-  case DarwinOld:
+-    return !mach_o::link(args, exitEarly, stdoutOS, stderrOS);
+   case Wasm:
+     return !lld::wasm::link(args, exitEarly, stdoutOS, stderrOS);
+   default:
--- a/nix/windows/make_msys2_packages.sh
+++ b/nix/windows/make_msys2_packages.sh
@ -10,7 +10,7 @@ curl -L https://mirror.msys2.org/msys/x86_64/pacman-mirrors-20220205-1-any.pkg.t
 curl -L https://raw.githubusercontent.com/msys2/MSYS2-packages/master/pacman/pacman.conf | grep -v SigLevel | sed s\|/etc/pacman.d\|$MSYS2DIR/etc/pacman.d\|g > $MSYS2DIR/etc/pacman.conf

 fakeroot pacman --root $MSYS2DIR --config $MSYS2DIR/etc/pacman.conf -Syy
-pacman --root $MSYS2DIR --config $MSYS2DIR/etc/pacman.conf --cachedir $MSYS2DIR/msys/cache -Sp mingw-w64-x86_64-rust mingw-w64-x86_64-cmake mingw-w64-x86_64-ninja mingw-w64-x86_64-python3.9 mingw-w64-x86_64-python-numpy > $MSYS2DIR/packages.txt
+pacman --root $MSYS2DIR --config $MSYS2DIR/etc/pacman.conf --cachedir $MSYS2DIR/msys/cache -Sp mingw-w64-x86_64-rust mingw-w64-x86_64-cmake mingw-w64-x86_64-ninja mingw-w64-x86_64-python3.9 mingw-w64-x86_64-python-numpy mingw-w64-x86_64-python-setuptools > $MSYS2DIR/packages.txt

 echo "{ pkgs } : [" > msys2_packages.nix
 while read package; do
--- a/nix/windows/makepkg.conf
+++ b/nix/windows/makepkg.conf
@ -0,0 +1,2 @@
+PKGEXT='.pkg.tar.zst'
+SRCEXT='.src.tar.gz'
--- a/nix/windows/msys2_packages.nix
+++ b/nix/windows/msys2_packages.nix
@ -6,8 +6,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-zlib-1.2.11-9-any.pkg.tar.zst";
-  sha256 = "0fb3xbw9a0ah4viwp3a7hr5phnc7mvcl9ba2yjidncpqmspypacx";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-zlib-1.2.12-1-any.pkg.tar.zst";
+  sha256 = "1b461ic5s3hjk3y70ldik82ny08rdywn1zfqa8d2jyyvnh4dya77";
 })

 (pkgs.fetchurl {
@ -16,13 +16,13 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-headers-git-9.0.0.6451.a3f6d363d-1-any.pkg.tar.zst";
-  sha256 = "1ngnjb9vgk295wlwqandm0nhqqdfrp584kx3nfshxkhwmj5gpzxk";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-headers-git-9.0.0.6454.b4445ee52-1-any.pkg.tar.zst";
+  sha256 = "0wyg5ad3fh2lwd7avxvpncipj5wxmp647l43wzr1l3rrkd820yy3";
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-crt-git-9.0.0.6451.a3f6d363d-1-any.pkg.tar.zst";
-  sha256 = "1ccipidbsjncdhr48k50ia53dwn7v3ghdl8f1svgwvnh3mrx0bww";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-crt-git-9.0.0.6454.b4445ee52-1-any.pkg.tar.zst";
+  sha256 = "0bnzwgf395fbwbsq8900prj409b081hi0dd76kak6d971xqyy2r4";
 })

 (pkgs.fetchurl {
@ -46,8 +46,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-libwinpthread-git-9.0.0.6451.a3f6d363d-1-any.pkg.tar.zst";
-  sha256 = "0qdy79l5y02lw2xa8i3j6yayhz8a7awfgyyd82pcmbzwx57q2xqb";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-libwinpthread-git-9.0.0.6454.b4445ee52-1-any.pkg.tar.zst";
+  sha256 = "181fm72bi6cs348hixkqjzivizzcsyn2lxvnbqprx4366prjf7nn";
 })

 (pkgs.fetchurl {
@ -61,8 +61,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-winpthreads-git-9.0.0.6451.a3f6d363d-1-any.pkg.tar.zst";
-  sha256 = "08zwgkrp45y5ry8avz61krasjkk4k4a5rrdz4nd78bbbah84mpgz";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-winpthreads-git-9.0.0.6454.b4445ee52-1-any.pkg.tar.zst";
+  sha256 = "0n3pim85wlsc93y9sh06rnfraqgzbz300sp9hd8n7wgvcsmpj9rx";
 })

 (pkgs.fetchurl {
@ -86,8 +86,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-expat-2.4.7-1-any.pkg.tar.zst";
-  sha256 = "19qh3kk2kmkkzxirpx1swgfsfb29gy9q8qgdmrzzbwrqrn8vs77j";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-expat-2.4.8-1-any.pkg.tar.zst";
+  sha256 = "1qkw4k61ddaflns5ms0xh0czbx99wxhs0dfbk8sv8by2rkshl51k";
 })

 (pkgs.fetchurl {
@ -101,8 +101,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-libidn2-2.3.1-1-any.pkg.tar.zst";
-  sha256 = "00vm6d56ldr1f4h0dn15j0ja17dif45qxlxaqv4x5nw555frklf5";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-libidn2-2.3.2-1-any.pkg.tar.zst";
+  sha256 = "0p694g8g716zyvcxc48xmdanjyrkp3ir4naqlradrw2szy9bj800";
 })

 (pkgs.fetchurl {
@ -231,8 +231,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-cmake-3.22.3-2-any.pkg.tar.zst";
-  sha256 = "1xp8n5s98va7a9cq36d9p49lk32yv9vkvlayc4d4j465xzm21hgp";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-cmake-3.23.0-1-any.pkg.tar.zst";
+  sha256 = "1gcmm3bd29zfd88ack6xdqwmbskyvhb4ymrfspayk4jfcj4svky5";
 })

 (pkgs.fetchurl {
@ -266,8 +266,8 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-sqlite3-3.38.1-1-any.pkg.tar.zst";
-  sha256 = "04h4m72mwmad82nzrl5qj9wlsinjs7z7bsbbq17dxkx92aj75p26";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-sqlite3-3.38.2-1-any.pkg.tar.zst";
+  sha256 = "14agi4611h5400j7bqh1w5i5qbhp4hp6apzaddilxq97y37vj90q";
 })

 (pkgs.fetchurl {
@ -291,12 +291,17 @@
 })

 (pkgs.fetchurl {
-  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-openblas-0.3.20-1-any.pkg.tar.zst";
-  sha256 = "1adbbycbvs2nkjhgap92fk3x0vqfjb3ghhvyd1xlnn56c5n0iphf";
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-openblas-0.3.20-2-any.pkg.tar.zst";
+  sha256 = "1cj0j06b2xhcvq9v6jx5cn130r8pkv2xa885f3z3z98kmrifjw0l";
 })

 (pkgs.fetchurl {
  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-python-numpy-1.21.5-1-any.pkg.tar.zst";
  sha256 = "10bhfq65nrzxipgy75bqaad74daif4ay06phwvbx70b9j0wm33c3";
 })
+
+(pkgs.fetchurl {
+  url = "https://mirror.msys2.org/mingw/mingw64/mingw-w64-x86_64-python-setuptools-59.8.0-2-any.pkg.tar.zst";
+  sha256 = "1jbvsmh1r00yb6fm8by6z7xp9069f9lkj73jrsnxmflmvpdkjl5c";
+})
 ]
Author	SHA1	Message	Date
ychenfo	100e441a44	f	2022-04-05 15:28:21 +08:00
ychenfo	0a2dfab9a1	nac3core: add bound check for list slice	2022-04-05 14:29:40 +08:00
ychenfo	0fb9998a96	nac3core: add location information to codegen context	2022-04-05 14:29:40 +08:00
Sebastien Bourdeauducq	e05b0bf5dc	flake: update nixpkgs	2022-04-05 10:10:08 +08:00
Sebastien Bourdeauducq	8eda0affc9	windows: add wine-msys2-build	2022-04-05 10:06:36 +08:00
Sebastien Bourdeauducq	75c53b40a3	windows: update msys2 packages, add setuptools to environment	2022-04-05 10:06:14 +08:00
pca006132	0d10044d66	Merge pull request 'Fix float**int with negative power' (#254 ) from neg_powi_fix into master Reviewed-on: M-Labs/nac3#254	2022-04-04 22:43:20 +08:00
ychenfo	23b7f4ef18	nac3standalone: add tests for power	2022-04-04 22:10:56 +08:00
ychenfo	710904f975	nac3core: fix powi with negative integer power	2022-04-04 22:10:56 +08:00
Sebastien Bourdeauducq	4bf452ec5a	windows: do not check dependencies when making package	2022-04-04 16:03:59 +08:00
Sebastien Bourdeauducq	9fdce11efe	windows: depend on python	2022-04-04 15:21:34 +08:00
Sebastien Bourdeauducq	f24ef85aed	hydra: use msys2 type	2022-04-04 15:03:53 +08:00
Sebastien Bourdeauducq	4a19787f10	README: update	2022-04-04 15:03:44 +08:00
Sebastien Bourdeauducq	8209c0a475	windows: create MSYS2 package	2022-04-04 14:24:47 +08:00
pca006132	4f66bdeda9	Merge pull request 'nac3core: do not get llvm value too eagerly for kernel invariant' (#253 ) from kernel_invariant_fix into master Reviewed-on: M-Labs/nac3#253	2022-03-31 12:48:49 +08:00
Sebastien Bourdeauducq	57369896d7	update dependencies	2022-03-31 10:40:18 +08:00
ychenfo	2edeb31d21	nac3core: do not get llvm value too eagerly for kernel invariant	2022-03-31 10:28:16 +08:00
ychenfo	b8ef44d64e	nac3standalone: add test for default param	2022-03-30 04:05:47 +08:00
ychenfo	c3156afebd	nac3core: fix broken tests	2022-03-30 04:05:47 +08:00
ychenfo	388c9b7241	nac3core: better check and err msg for default param	2022-03-30 04:05:47 +08:00
ychenfo	e52d7fc97a	nac3artiq: resolve unsigned int host variable as defautl param	2022-03-30 04:05:47 +08:00
ychenfo	6ab73a223c	nac3core/artiq: support default param of option type	2022-03-30 04:05:47 +08:00
ychenfo	a38cc04444	nac3core: assert statement	2022-03-29 06:56:40 +08:00
ychenfo	1f5826d352	fix ternary if (#250 ) Use store and load to handle if expression as the blocks might be changed when generating sub-expressions. Reviewed-on: M-Labs/nac3#250 Co-authored-by: ychenfo <yc@m-labs.hk> Co-committed-by: ychenfo <yc@m-labs.hk>	2022-03-29 06:54:00 +08:00
Sebastien Bourdeauducq	94eebde4ea	README: add note about MSVC Python	2022-03-28 10:45:01 +08:00
Sebastien Bourdeauducq	63ec382673	README: update Windows instructions	2022-03-27 19:36:02 +08:00
Sebastien Bourdeauducq	0ca1a7bedb	windows: work around broken LLD install script	2022-03-27 19:14:02 +08:00
Sebastien Bourdeauducq	201ca3f63d	Revert "nac3artiq: use lld.exe on Windows" This reverts commit `19182759cd`.	2022-03-27 19:09:11 +08:00
Sebastien Bourdeauducq	19182759cd	nac3artiq: use lld.exe on Windows	2022-03-27 18:41:38 +08:00
Sebastien Bourdeauducq	edd039abdc	windows: build LLD	2022-03-27 18:41:23 +08:00
Sebastien Bourdeauducq	3852cc1058	windows: don't fixup LLVM	2022-03-27 18:38:23 +08:00
Sebastien Bourdeauducq	0600ee8efa	nac3artiq: use correct lld invokation on Windows	2022-03-27 18:25:14 +08:00
ychenfo	bed33a7421	nac3standalone: add tests for tuple	2022-03-27 10:31:20 +08:00
ychenfo	0d2b844a2e	nac3artiq: avoid getting tuple as pointer value	2022-03-27 10:31:20 +08:00
ychenfo	8d7e300a4a	nac3core: do not use const struct for tuple	2022-03-27 10:13:17 +08:00
ychenfo	10d623e36f	nac3core/artiq: fix tuple representation	2022-03-27 07:47:14 +08:00
ychenfo	000b128551	nac3artiq: cast none to correct ptr type (#241 )	2022-03-26 23:32:50 +08:00
Sebastien Bourdeauducq	e4581a6d9b	nac3standalone/demo: fix return type in loop.py	2022-03-26 21:10:12 +08:00
pca006132	1a82d296e7	nac3core/codegen: prevent users from modifying loop counter Fixes #211	2022-03-26 20:58:37 +08:00
pca006132	bf067e2481	nac3artiq: implement attribute writeback We will only writeback attributes that are supported by the current RPC implementation: primitives, tuple and lists of lists... of primitives.	2022-03-26 20:13:58 +08:00
ychenfo	ba8ed6c663	nac3artiq: handle recursive types properly	2022-03-26 18:54:21 +08:00
ychenfo	26a4834254	fix warnings	2022-03-26 18:52:08 +08:00
Sebastien Bourdeauducq	1ad4b0227c	windows: fix src location	2022-03-26 15:46:21 +08:00
Sebastien Bourdeauducq	6288a66dc5	windows: fix cargo lockfile location	2022-03-26 15:23:31 +08:00
Sebastien Bourdeauducq	de4320eefb	improve package names	2022-03-26 15:15:59 +08:00
Sebastien Bourdeauducq	a380cd5010	move all Nix files to one folder	2022-03-26 15:13:43 +08:00
ychenfo	80631fc92b	Option type support (#224 ) Co-authored-by: ychenfo <yc@m-labs.hk> Co-committed-by: ychenfo <yc@m-labs.hk>	2022-03-26 15:09:15 +08:00