nac3artiq/src/lib.rs

@@ -650,6 +650,11 @@ impl Nac3 {
                             }
                         }
                     }
+                    TopLevelDef::Variable { .. } => {
+                        return Err(CompileError::new_err(String::from(
+                            "Unsupported @rpc annotation on global variable",
+                        )))
+                    }
                 }
             }
         }

nac3artiq/src/symbol_resolver.rs

@@ -1470,6 +1470,7 @@ impl SymbolResolver for Resolver {
         &self,
         id: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         let sym_value = {
             let id_to_val = self.0.id_to_pyval.read();

nac3core/src/codegen/expr.rs

@@ -977,6 +977,7 @@ pub fn gen_call<'ctx, G: CodeGenerator>(
             TopLevelDef::Class { .. } => {
                 return Ok(Some(generator.gen_constructor(ctx, fun.0, &def, params)?))
             }
+            TopLevelDef::Variable { .. } => unreachable!(),
         }
     }
     .or_else(|_: String| {
@@ -2885,7 +2886,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
             Some((_, Some(static_value), _)) => ValueEnum::Static(static_value.clone()),
             None => {
                 let resolver = ctx.resolver.clone();
-                resolver.get_symbol_value(*id, ctx).unwrap()
+                resolver.get_symbol_value(*id, ctx, generator).unwrap()
             }
         },
         ExprKind::List { elts, .. } => {

nac3core/src/codegen/mod.rs

@@ -853,10 +853,9 @@ pub fn gen_func_impl<
     builder.position_at_end(init_bb);
     let body_bb = context.append_basic_block(fn_val, "body");
 
+    // Store non-vararg argument values into local variables
     let mut var_assignment = HashMap::new();
     let offset = u32::from(has_sret);
-
-    // Store non-vararg argument values into local variables
     for (n, arg) in args.iter().enumerate().filter(|(_, arg)| !arg.is_vararg) {
         let param = fn_val.get_nth_param((n as u32) + offset).unwrap();
         let local_type = get_llvm_type(

nac3core/src/codegen/stmt.rs

@@ -1828,6 +1828,37 @@ pub fn gen_stmt<G: CodeGenerator>(
                 stmt.location,
             );
         }
+        StmtKind::Global { names, .. } => {
+            let registered_globals = ctx
+                .top_level
+                .definitions
+                .read()
+                .iter()
+                .filter_map(|def| {
+                    if let TopLevelDef::Variable { simple_name, ty, .. } = &*def.read() {
+                        Some((*simple_name, *ty))
+                    } else {
+                        None
+                    }
+                })
+                .collect_vec();
+
+            for id in names {
+                let Some((_, ty)) = registered_globals.iter().find(|(name, _)| name == id) else {
+                    return Err(format!("{id} is not a global at {}", stmt.location));
+                };
+
+                let resolver = ctx.resolver.clone();
+                let ptr = resolver
+                    .get_symbol_value(*id, ctx, generator)
+                    .map(|val| val.to_basic_value_enum(ctx, generator, *ty))
+                    .transpose()?
+                    .map(BasicValueEnum::into_pointer_value)
+                    .unwrap();
+
+                ctx.var_assignment.insert(*id, (ptr, None, 0));
+            }
+        }
         _ => unimplemented!(),
     };
     Ok(())

nac3core/src/codegen/test.rs

@@ -28,7 +28,7 @@ use crate::{
         DefinitionId, FunInstance, TopLevelContext, TopLevelDef,
     },
     typecheck::{
-        type_inferencer::{FunctionData, Inferencer, PrimitiveStore},
+        type_inferencer::{FunctionData, IdentifierInfo, Inferencer, PrimitiveStore},
         typedef::{FunSignature, FuncArg, Type, TypeEnum, Unifier, VarMap},
     },
 };
@@ -67,6 +67,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }
@@ -141,7 +142,8 @@ fn test_primitives() {
     };
     let mut virtual_checks = Vec::new();
     let mut calls = HashMap::new();
-    let mut identifiers: HashSet<_> = ["a".into(), "b".into()].into();
+    let mut identifiers: HashMap<_, _> =
+        ["a".into(), "b".into()].map(|id| (id, IdentifierInfo::default())).into();
     let mut inferencer = Inferencer {
         top_level: &top_level,
         function_data: &mut function_data,
@@ -320,7 +322,8 @@ fn test_simple_call() {
     };
     let mut virtual_checks = Vec::new();
     let mut calls = HashMap::new();
-    let mut identifiers: HashSet<_> = ["a".into(), "foo".into()].into();
+    let mut identifiers: HashMap<_, _> =
+        ["a".into(), "foo".into()].map(|id| (id, IdentifierInfo::default())).into();
     let mut inferencer = Inferencer {
         top_level: &top_level,
         function_data: &mut function_data,

nac3core/src/symbol_resolver.rs

@@ -369,6 +369,7 @@ pub trait SymbolResolver {
         &self,
         str: StrRef,
         ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>>;
 
     fn get_default_param_value(&self, expr: &Expr) -> Option<SymbolValue>;

nac3core/src/toplevel/composer.rs

@@ -1,13 +1,13 @@
 use std::rc::Rc;
 
-use nac3parser::ast::fold::Fold;
+use nac3parser::ast::{fold::Fold, ExprKind};
 
 use super::*;
 use crate::{
     codegen::{expr::get_subst_key, stmt::exn_constructor},
     symbol_resolver::SymbolValue,
     typecheck::{
-        type_inferencer::{FunctionData, Inferencer},
+        type_inferencer::{FunctionData, IdentifierInfo, Inferencer},
         typedef::{TypeVar, VarMap},
     },
 };
@@ -101,7 +101,8 @@ impl TopLevelComposer {
             .iter()
             .map(|def_ast| match *def_ast.0.read() {
                 TopLevelDef::Class { name, .. } => name.to_string(),
-                TopLevelDef::Function { simple_name, .. } => simple_name.to_string(),
+                TopLevelDef::Function { simple_name, .. }
+                | TopLevelDef::Variable { simple_name, .. } => simple_name.to_string(),
             })
             .collect_vec();
 
@@ -381,8 +382,58 @@ impl TopLevelComposer {
                 ))
             }
 
+            ast::StmtKind::AnnAssign { target, annotation, .. } => {
+                let ExprKind::Name { id: name, .. } = target.node else {
+                    return Err(format!(
+                        "global variable declaration must be an identifier (at {})",
+                        ast.location
+                    ));
+                };
+
+                if self.keyword_list.contains(&name) {
+                    return Err(format!(
+                        "cannot use keyword `{}` as a class name (at {})",
+                        name,
+                        ast.location
+                    ));
+                }
+
+                let global_var_name = if mod_path.is_empty() {
+                    name.to_string()
+                } else {
+                    format!("{mod_path}.{name}")
+                };
+                if !defined_names.insert(global_var_name.clone()) {
+                    return Err(format!(
+                        "global variable `{}` defined twice (at {})",
+                        global_var_name,
+                        ast.location
+                    ));
+                }
+
+                let ty_to_be_unified = self.unifier.get_dummy_var().ty;
+                self.definition_ast_list.push((
+                    RwLock::new(Self::make_top_level_variable_def(
+                        global_var_name,
+                        name,
+                        // dummy here, unify with correct type later,
+                        ty_to_be_unified,
+                        *(annotation.clone()),
+                        resolver,
+                        Some(ast.location),
+                    )).into(),
+                    None,
+                ));
+
+                Ok((
+                    name,
+                    DefinitionId(self.definition_ast_list.len() - 1),
+                    Some(ty_to_be_unified),
+                ))
+            }
+
             _ => Err(format!(
-                "registrations of constructs other than top level classes/functions are not supported (at {})",
+                "registrations of constructs other than top level classes/functions/variables are not supported (at {})",
                 ast.location
             )),
         }
@@ -396,6 +447,7 @@ impl TopLevelComposer {
         if inference {
             self.analyze_function_instance()?;
         }
+        self.analyze_top_level_variables()?;
         Ok(())
     }
 
@@ -500,6 +552,7 @@ impl TopLevelComposer {
             }
             Ok(())
         };
+
         let mut errors = HashSet::new();
         for (class_def, class_ast) in def_list.iter().skip(self.builtin_num) {
             if class_ast.is_none() {
@@ -853,7 +906,6 @@ impl TopLevelComposer {
         let unifier = self.unifier.borrow_mut();
         let primitives_store = &self.primitives_ty;
 
-        let mut errors = HashSet::new();
         let mut analyze = |function_def: &Arc<RwLock<TopLevelDef>>, function_ast: &Option<Stmt>| {
             let mut function_def = function_def.write();
             let function_def = &mut *function_def;
@@ -1128,6 +1180,8 @@ impl TopLevelComposer {
             })?;
             Ok(())
         };
+
+        let mut errors = HashSet::new();
         for (function_def, function_ast) in def_list.iter().skip(self.builtin_num) {
             if function_ast.is_none() {
                 continue;
@@ -1702,7 +1756,6 @@ impl TopLevelComposer {
             }
         }
 
-        let mut errors = HashSet::new();
         let mut analyze = |i, def: &Arc<RwLock<TopLevelDef>>, ast: &Option<Stmt>| {
             let class_def = def.read();
             if let TopLevelDef::Class {
@@ -1845,6 +1898,8 @@ impl TopLevelComposer {
             }
             Ok(())
         };
+
+        let mut errors = HashSet::new();
         for (i, (def, ast)) in definition_ast_list.iter().enumerate().skip(self.builtin_num) {
             if ast.is_none() {
                 continue;
@@ -2003,11 +2058,12 @@ impl TopLevelComposer {
                         })
                     };
                     let mut identifiers = {
-                        let mut result: HashSet<_> = HashSet::new();
+                        let mut result = HashMap::new();
                         if self_type.is_some() {
-                            result.insert("self".into());
+                            result.insert("self".into(), IdentifierInfo::default());
                         }
-                        result.extend(inst_args.iter().map(|x| x.name));
+                        result
+                            .extend(inst_args.iter().map(|x| (x.name, IdentifierInfo::default())));
                         result
                     };
                     let mut calls: HashMap<CodeLocation, CallId> = HashMap::new();
@@ -2172,4 +2228,57 @@ impl TopLevelComposer {
         }
         Ok(())
     }
+
+    /// Step 6. Analyze and populate the types of global variables.
+    fn analyze_top_level_variables(&mut self) -> Result<(), HashSet<String>> {
+        let def_list = &self.definition_ast_list;
+        let temp_def_list = self.extract_def_list();
+        let unifier = &mut self.unifier;
+        let primitives_store = &self.primitives_ty;
+
+        let mut analyze = |variable_def: &Arc<RwLock<TopLevelDef>>| -> Result<_, HashSet<String>> {
+            let variable_def = &mut *variable_def.write();
+
+            let TopLevelDef::Variable { ty: dummy_ty, ty_decl, resolver, loc, .. } = variable_def
+            else {
+                // not top level variable def, skip
+                return Ok(());
+            };
+
+            let resolver = &**resolver.as_ref().unwrap();
+
+            let ty_annotation = parse_ast_to_type_annotation_kinds(
+                resolver,
+                &temp_def_list,
+                unifier,
+                primitives_store,
+                ty_decl,
+                HashMap::new(),
+            )?;
+            let ty_from_ty_annotation = get_type_from_type_annotation_kinds(
+                &temp_def_list,
+                unifier,
+                primitives_store,
+                &ty_annotation,
+                &mut None,
+            )?;
+
+            unifier.unify(*dummy_ty, ty_from_ty_annotation).map_err(|e| {
+                HashSet::from([e.at(Some(loc.unwrap())).to_display(unifier).to_string()])
+            })?;
+            Ok(())
+        };
+
+        let mut errors = HashSet::new();
+        for (variable_def, _) in def_list.iter().skip(self.builtin_num) {
+            if let Err(e) = analyze(variable_def) {
+                errors.extend(e);
+            }
+        }
+        if !errors.is_empty() {
+            return Err(errors);
+        }
+
+        Ok(())
+    }
 }

nac3core/src/toplevel/helper.rs

@@ -391,6 +391,9 @@ impl TopLevelDef {
                     r
                 }
             ),
+            TopLevelDef::Variable { name, ty, .. } => {
+                format!("Variable {{ name: {name:?}, ty: {:?} }}", unifier.stringify(*ty),)
+            }
         }
     }
 }
@@ -592,6 +595,18 @@ impl TopLevelComposer {
         }
     }
 
+    #[must_use]
+    pub fn make_top_level_variable_def(
+        name: String,
+        simple_name: StrRef,
+        ty: Type,
+        ty_decl: Expr,
+        resolver: Option<Arc<dyn SymbolResolver + Send + Sync>>,
+        loc: Option<Location>,
+    ) -> TopLevelDef {
+        TopLevelDef::Variable { name, simple_name, ty, ty_decl, resolver, loc }
+    }
+
     #[must_use]
     pub fn make_class_method_name(mut class_name: String, method_name: &str) -> String {
         class_name.push('.');

nac3core/src/toplevel/mod.rs

@@ -10,7 +10,7 @@ use inkwell::values::BasicValueEnum;
 use itertools::Itertools;
 use parking_lot::RwLock;
 
-use nac3parser::ast::{self, Location, Stmt, StrRef};
+use nac3parser::ast::{self, Expr, Location, Stmt, StrRef};
 
 use crate::{
     codegen::{CodeGenContext, CodeGenerator},
@@ -148,6 +148,25 @@ pub enum TopLevelDef {
         /// Definition location.
         loc: Option<Location>,
     },
+    Variable {
+        /// Qualified name of the global variable, should be unique globally.
+        name: String,
+
+        /// Simple name, the same as in method/function definition.
+        simple_name: StrRef,
+
+        /// Type of the global variable.
+        ty: Type,
+
+        /// The declared type of the global variable.
+        ty_decl: Expr,
+
+        /// Symbol resolver of the module defined the class.
+        resolver: Option<Arc<dyn SymbolResolver + Send + Sync>>,
+
+        /// Definition location.
+        loc: Option<Location>,
+    },
 }
 
 pub struct TopLevelContext {

nac3core/src/toplevel/test.rs

@@ -65,6 +65,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }

nac3core/src/typecheck/function_check.rs

@@ -1,4 +1,7 @@
-use std::{collections::HashSet, iter::once};
+use std::{
+    collections::{HashMap, HashSet},
+    iter::once,
+};
 
 use nac3parser::ast::{
     self, Constant, Expr, ExprKind,
@@ -7,7 +10,7 @@ use nac3parser::ast::{
 };
 
 use super::{
-    type_inferencer::Inferencer,
+    type_inferencer::{IdentifierInfo, Inferencer},
     typedef::{Type, TypeEnum},
 };
 use crate::toplevel::helper::PrimDef;
@@ -24,15 +27,15 @@ impl<'a> Inferencer<'a> {
     fn check_pattern(
         &mut self,
         pattern: &Expr<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<(), HashSet<String>> {
         match &pattern.node {
             ExprKind::Name { id, .. } if id == &"none".into() => {
                 Err(HashSet::from([format!("cannot assign to a `none` (at {})", pattern.location)]))
             }
             ExprKind::Name { id, .. } => {
-                if !defined_identifiers.contains(id) {
-                    defined_identifiers.insert(*id);
+                if !defined_identifiers.contains_key(id) {
+                    defined_identifiers.insert(*id, IdentifierInfo::default());
                 }
                 self.should_have_value(pattern)?;
                 Ok(())
@@ -72,7 +75,7 @@ impl<'a> Inferencer<'a> {
     fn check_expr(
         &mut self,
         expr: &Expr<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<(), HashSet<String>> {
         // there are some cases where the custom field is None
         if let Some(ty) = &expr.custom {
@@ -93,7 +96,7 @@ impl<'a> Inferencer<'a> {
                     return Ok(());
                 }
                 self.should_have_value(expr)?;
-                if !defined_identifiers.contains(id) {
+                if !defined_identifiers.contains_key(id) {
                     match self.function_data.resolver.get_symbol_type(
                         self.unifier,
                         &self.top_level.definitions.read(),
@@ -101,7 +104,7 @@ impl<'a> Inferencer<'a> {
                         *id,
                     ) {
                         Ok(_) => {
-                            self.defined_identifiers.insert(*id);
+                            self.defined_identifiers.insert(*id, IdentifierInfo::default());
                         }
                         Err(e) => {
                             return Err(HashSet::from([format!(
@@ -174,9 +177,7 @@ impl<'a> Inferencer<'a> {
                 let mut defined_identifiers = defined_identifiers.clone();
                 for arg in &args.args {
                     // TODO: should we check the types here?
-                    if !defined_identifiers.contains(&arg.node.arg) {
-                        defined_identifiers.insert(arg.node.arg);
-                    }
+                    defined_identifiers.entry(arg.node.arg).or_default();
                 }
                 self.check_expr(body, &mut defined_identifiers)?;
             }
@@ -239,7 +240,7 @@ impl<'a> Inferencer<'a> {
     fn check_stmt(
         &mut self,
         stmt: &Stmt<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<bool, HashSet<String>> {
         match &stmt.node {
             StmtKind::For { target, iter, body, orelse, .. } => {
@@ -265,9 +266,11 @@ impl<'a> Inferencer<'a> {
                 let body_returned = self.check_block(body, &mut body_identifiers)?;
                 let orelse_returned = self.check_block(orelse, &mut orelse_identifiers)?;
 
-                for ident in &body_identifiers {
-                    if !defined_identifiers.contains(ident) && orelse_identifiers.contains(ident) {
-                        defined_identifiers.insert(*ident);
+                for ident in body_identifiers.keys() {
+                    if !defined_identifiers.contains_key(ident)
+                        && orelse_identifiers.contains_key(ident)
+                    {
+                        defined_identifiers.insert(*ident, IdentifierInfo::default());
                     }
                 }
                 Ok(body_returned && orelse_returned)
@@ -298,7 +301,7 @@ impl<'a> Inferencer<'a> {
                     let mut defined_identifiers = defined_identifiers.clone();
                     let ast::ExcepthandlerKind::ExceptHandler { name, body, .. } = &handler.node;
                     if let Some(name) = name {
-                        defined_identifiers.insert(*name);
+                        defined_identifiers.insert(*name, IdentifierInfo::default());
                     }
                     self.check_block(body, &mut defined_identifiers)?;
                 }
@@ -362,6 +365,40 @@ impl<'a> Inferencer<'a> {
                 }
                 Ok(true)
             }
+            StmtKind::Global { names, .. } => {
+                for id in names {
+                    if let Some(id_info) = defined_identifiers.get(id) {
+                        if !id_info.is_global {
+                            return Err(HashSet::from([format!(
+                                "name '{id}' is assigned to before global declaration at {}",
+                                stmt.location,
+                            )]));
+                        }
+
+                        continue;
+                    }
+
+                    match self.function_data.resolver.get_symbol_type(
+                        self.unifier,
+                        &self.top_level.definitions.read(),
+                        self.primitives,
+                        *id,
+                    ) {
+                        Ok(_) => {
+                            self.defined_identifiers
+                                .insert(*id, IdentifierInfo { is_global: true });
+                        }
+                        Err(e) => {
+                            return Err(HashSet::from([format!(
+                                "type error at identifier `{}` ({}) at {}",
+                                id, e, stmt.location
+                            )]))
+                        }
+                    }
+                }
+
+                Ok(false)
+            }
             // break, raise, etc.
             _ => Ok(false),
         }
@@ -370,7 +407,7 @@ impl<'a> Inferencer<'a> {
     pub fn check_block(
         &mut self,
         block: &[Stmt<Option<Type>>],
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<bool, HashSet<String>> {
         let mut ret = false;
         for stmt in block {

nac3core/src/typecheck/type_inferencer/mod.rs

@@ -88,6 +88,20 @@ impl PrimitiveStore {
     }
 }
 
+/// Information regarding a defined identifier.
+#[derive(Clone, Copy, Debug, Default)]
+pub struct IdentifierInfo {
+    /// Whether this identifier refers to a global variable.
+    pub is_global: bool,
+}
+
+impl IdentifierInfo {
+    #[must_use]
+    pub fn new() -> IdentifierInfo {
+        IdentifierInfo::default()
+    }
+}
+
 pub struct FunctionData {
     pub resolver: Arc<dyn SymbolResolver + Send + Sync>,
     pub return_type: Option<Type>,
@@ -96,7 +110,7 @@ pub struct FunctionData {
 
 pub struct Inferencer<'a> {
     pub top_level: &'a TopLevelContext,
-    pub defined_identifiers: HashSet<StrRef>,
+    pub defined_identifiers: HashMap<StrRef, IdentifierInfo>,
     pub function_data: &'a mut FunctionData,
     pub unifier: &'a mut Unifier,
     pub primitives: &'a PrimitiveStore,
@@ -228,9 +242,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
                                 handler.location,
                             ));
                             if let Some(name) = name {
-                                if !self.defined_identifiers.contains(&name) {
-                                    self.defined_identifiers.insert(name);
-                                }
+                                self.defined_identifiers.entry(name).or_default();
                                 if let Some(old_typ) = self.variable_mapping.insert(name, typ) {
                                     let loc = handler.location;
                                     self.unifier.unify(old_typ, typ).map_err(|e| {
@@ -382,6 +394,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
             | ast::StmtKind::Continue { .. }
             | ast::StmtKind::Expr { .. }
             | ast::StmtKind::For { .. }
+            | ast::StmtKind::Global { .. }
             | ast::StmtKind::Pass { .. }
             | ast::StmtKind::Try { .. } => {}
             ast::StmtKind::If { test, .. } | ast::StmtKind::While { test, .. } => {
@@ -553,7 +566,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
                         unreachable!("must be tobj")
                     }
                 } else {
-                    if !self.defined_identifiers.contains(id) {
+                    if !self.defined_identifiers.contains_key(id) {
                         match self.function_data.resolver.get_symbol_type(
                             self.unifier,
                             &self.top_level.definitions.read(),
@@ -561,7 +574,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
                             *id,
                         ) {
                             Ok(_) => {
-                                self.defined_identifiers.insert(*id);
+                                self.defined_identifiers.insert(*id, IdentifierInfo::default());
                             }
                             Err(e) => {
                                 return report_error(
@@ -626,8 +639,8 @@ impl<'a> Inferencer<'a> {
     fn infer_pattern<T>(&mut self, pattern: &ast::Expr<T>) -> Result<(), InferenceError> {
         match &pattern.node {
             ExprKind::Name { id, .. } => {
-                if !self.defined_identifiers.contains(id) {
-                    self.defined_identifiers.insert(*id);
+                if !self.defined_identifiers.contains_key(id) {
+                    self.defined_identifiers.insert(*id, IdentifierInfo::default());
                 }
                 Ok(())
             }
@@ -736,8 +749,8 @@ impl<'a> Inferencer<'a> {
         let mut defined_identifiers = self.defined_identifiers.clone();
         for arg in &args.args {
             let name = &arg.node.arg;
-            if !defined_identifiers.contains(name) {
-                defined_identifiers.insert(*name);
+            if !defined_identifiers.contains_key(name) {
+                defined_identifiers.insert(*name, IdentifierInfo::default());
             }
         }
         let fn_args: Vec<_> = args

nac3core/src/typecheck/type_inferencer/test.rs

@@ -9,7 +9,7 @@ use nac3parser::{ast::FileName, parser::parse_program};
 
 use super::*;
 use crate::{
-    codegen::CodeGenContext,
+    codegen::{CodeGenContext, CodeGenerator},
     symbol_resolver::ValueEnum,
     toplevel::{helper::PrimDef, DefinitionId, TopLevelDef},
     typecheck::{magic_methods::with_fields, typedef::*},
@@ -43,6 +43,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }
@@ -519,7 +520,7 @@ impl TestEnvironment {
             primitives: &mut self.primitives,
             virtual_checks: &mut self.virtual_checks,
             calls: &mut self.calls,
-            defined_identifiers: HashSet::default(),
+            defined_identifiers: HashMap::default(),
             in_handler: false,
         }
     }
@@ -595,8 +596,9 @@ fn test_basic(source: &str, mapping: &HashMap<&str, &str>, virtuals: &[(&str, &s
     println!("source:\n{source}");
     let mut env = TestEnvironment::new();
     let id_to_name = std::mem::take(&mut env.id_to_name);
-    let mut defined_identifiers: HashSet<_> = env.identifier_mapping.keys().copied().collect();
-    defined_identifiers.insert("virtual".into());
+    let mut defined_identifiers: HashMap<_, _> =
+        env.identifier_mapping.keys().copied().map(|id| (id, IdentifierInfo::default())).collect();
+    defined_identifiers.insert("virtual".into(), IdentifierInfo::default());
     let mut inferencer = env.get_inferencer();
     inferencer.defined_identifiers.clone_from(&defined_identifiers);
     let statements = parse_program(source, FileName::default()).unwrap();
@@ -741,8 +743,9 @@ fn test_primitive_magic_methods(source: &str, mapping: &HashMap<&str, &str>) {
     println!("source:\n{source}");
     let mut env = TestEnvironment::basic_test_env();
     let id_to_name = std::mem::take(&mut env.id_to_name);
-    let mut defined_identifiers: HashSet<_> = env.identifier_mapping.keys().copied().collect();
-    defined_identifiers.insert("virtual".into());
+    let mut defined_identifiers: HashMap<_, _> =
+        env.identifier_mapping.keys().copied().map(|id| (id, IdentifierInfo::default())).collect();
+    defined_identifiers.insert("virtual".into(), IdentifierInfo::default());
     let mut inferencer = env.get_inferencer();
     inferencer.defined_identifiers.clone_from(&defined_identifiers);
     let statements = parse_program(source, FileName::default()).unwrap();

nac3standalone/demo/src/globals.py

@@ -0,0 +1,31 @@
+@extern
+def output_int32(x: int32):
+    ...
+
+@extern
+def output_int64(x: int64):
+    ...
+
+X: int32 = 0
+Y: int64 = int64(1)
+
+def f():
+    global X, Y
+    X = 1
+    Y = int64(2)
+
+def run() -> int32:
+    global X, Y
+
+    output_int32(X)
+    output_int64(Y)
+    f()
+    output_int32(X)
+    output_int64(Y)
+
+    X = 0
+    Y = int64(0)
+    output_int32(X)
+    output_int64(Y)
+
+    return 0

nac3standalone/src/basic_symbol_resolver.rs

@@ -6,7 +6,8 @@ use std::{
 use parking_lot::{Mutex, RwLock};
 
 use nac3core::{
-    codegen::CodeGenContext,
+    codegen::{CodeGenContext, CodeGenerator},
+    inkwell::{module::Linkage, values::BasicValue},
     nac3parser::ast::{self, StrRef},
     symbol_resolver::{SymbolResolver, SymbolValue, ValueEnum},
     toplevel::{DefinitionId, TopLevelDef},
@@ -49,20 +50,51 @@ impl SymbolResolver for Resolver {
 
     fn get_symbol_type(
         &self,
-        _: &mut Unifier,
+        unifier: &mut Unifier,
         _: &[Arc<RwLock<TopLevelDef>>],
-        _: &PrimitiveStore,
+        primitives: &PrimitiveStore,
         str: StrRef,
     ) -> Result<Type, String> {
-        self.0.id_to_type.lock().get(&str).copied().ok_or(format!("cannot get type of {str}"))
+        self.0
+            .id_to_type
+            .lock()
+            .get(&str)
+            .copied()
+            .or_else(|| {
+                self.0
+                    .module_globals
+                    .lock()
+                    .get(&str)
+                    .cloned()
+                    .map(|v| v.get_type(primitives, unifier))
+            })
+            .ok_or(format!("cannot get type of {str}"))
     }
 
     fn get_symbol_value<'ctx>(
         &self,
-        _: StrRef,
-        _: &mut CodeGenContext<'ctx, '_>,
+        str: StrRef,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
-        unimplemented!()
+        self.0.module_globals.lock().get(&str).cloned().map(|v| {
+            ctx.module
+                .get_global(&str.to_string())
+                .unwrap_or_else(|| {
+                    let ty = v.get_type(&ctx.primitives, &mut ctx.unifier);
+
+                    let init_val = ctx.gen_symbol_val(generator, &v, ty);
+                    let llvm_ty = init_val.get_type();
+
+                    let global = ctx.module.add_global(llvm_ty, None, &str.to_string());
+                    global.set_linkage(Linkage::LinkOnceAny);
+                    global.set_initializer(&init_val);
+
+                    global
+                })
+                .as_basic_value_enum()
+                .into()
+        })
     }
 
     fn get_identifier_def(&self, id: StrRef) -> Result<DefinitionId, HashSet<String>> {

nac3standalone/src/main.rs

@@ -245,6 +245,34 @@ fn handle_assignment_pattern(
     }
 }
 
+fn handle_global_var(
+    target: &Expr,
+    value: Option<&Expr>,
+    resolver: &(dyn SymbolResolver + Send + Sync),
+    internal_resolver: &ResolverInternal,
+) -> Result<(), String> {
+    let ExprKind::Name { id, .. } = target.node else {
+        return Err(format!(
+            "global variable declaration must be an identifier (at {})",
+            target.location,
+        ));
+    };
+
+    let Some(value) = value else {
+        return Err(format!("global variable `{id}` must be initialized in its definition"));
+    };
+
+    if let Ok(val) = parse_parameter_default_value(value, resolver) {
+        internal_resolver.add_module_global(id, val);
+        Ok(())
+    } else {
+        Err(format!(
+            "failed to evaluate this expression `{:?}` as a constant at {}",
+            target.node, target.location,
+        ))
+    }
+}
+
 fn main() {
     let cli = CommandLineArgs::parse();
     let CommandLineArgs { file_name, threads, opt_level, emit_llvm, triple, mcpu, target_features } =
@@ -297,8 +325,7 @@ fn main() {
     let program = match fs::read_to_string(file_name.clone()) {
         Ok(program) => program,
         Err(err) => {
-            println!("Cannot open input file: {err}");
-            return;
+            panic!("Cannot open input file: {err}");
         }
     };
 
@@ -340,10 +367,26 @@ fn main() {
                     unifier,
                     primitives,
                 ) {
-                    eprintln!("{err}");
-                    return;
+                    panic!("{err}");
                 }
             }
+
+            StmtKind::AnnAssign { target, value, .. } => {
+                if let Err(err) = handle_global_var(
+                    target,
+                    value.as_ref().map(Box::as_ref),
+                    resolver.as_ref(),
+                    internal_resolver.as_ref(),
+                ) {
+                    panic!("{err}");
+                }
+
+                let (name, def_id, _) = composer
+                    .register_top_level(stmt, Some(resolver.clone()), "__main__", true)
+                    .unwrap();
+                internal_resolver.add_id_def(name, def_id);
+            }
+
             // allow (and ignore) "from __future__ import annotations"
             StmtKind::ImportFrom { module, names, .. }
                 if module == &Some("__future__".into())