18 files changed, 475 insertions, 400 deletions

diff --git a/frontend/ast.cc b/frontend/ast.cc
index e067937..9a1f96b 100644
--- a/frontend/ast.cc
+++ b/frontend/ast.cc
@@ -24,7 +24,7 @@ namespace elna::frontend
         __builtin_unreachable();
     }
 
-    void empty_visitor::visit(named_type_expression *)
+    void empty_visitor::visit(type_expression *)
     {
         not_implemented();
     }
@@ -149,7 +149,7 @@ namespace elna::frontend
         not_implemented();
     }
 
-    void empty_visitor::visit(variable_expression *)
+    void empty_visitor::visit(named_expression *)
     {
         not_implemented();
     }
@@ -253,12 +253,7 @@ namespace elna::frontend
         return nullptr;
     }
 
-    type_expression::type_expression(const struct position position)
-        : node(position)
-    {
-    }
-
-    named_type_expression *type_expression::is_named()
+    named_expression *type_expression::is_named()
     {
         return nullptr;
     }
@@ -293,24 +288,46 @@ namespace elna::frontend
         return nullptr;
     }
 
-    named_type_expression::named_type_expression(const struct position position, const std::string& name)
-        : type_expression(position), name(name)
+    void type_expression::accept(parser_visitor *visitor)
     {
+        if (named_expression *node = is_named())
+        {
+            return visitor->visit(node);
+        }
+        else if (array_type_expression *node = is_array())
+        {
+            return visitor->visit(node);
+        }
+        else if (pointer_type_expression *node = is_pointer())
+        {
+            return visitor->visit(node);
+        }
+        else if (record_type_expression *node = is_record())
+        {
+            return visitor->visit(node);
+        }
+        else if (union_type_expression *node = is_union())
+        {
+            return visitor->visit(node);
+        }
+        else if (procedure_type_expression *node = is_procedure())
+        {
+            return visitor->visit(node);
+        }
+        else if (enumeration_type_expression *node = is_enumeration())
+        {
+            return visitor->visit(node);
+        }
+        __builtin_unreachable();
     }
 
-    void named_type_expression::accept(parser_visitor *visitor)
-    {
-        visitor->visit(this);
-    }
-
-    named_type_expression *named_type_expression::is_named()
+    type_expression::~type_expression()
     {
-        return this;
     }
 
     array_type_expression::array_type_expression(const struct position position,
             type_expression *base, const std::uint32_t size)
-        : type_expression(position), m_base(base), size(size)
+        : node(position), m_base(base), size(size)
     {
     }
 
@@ -336,7 +353,7 @@ namespace elna::frontend
 
     pointer_type_expression::pointer_type_expression(const struct position position,
             type_expression *base)
-        : type_expression(position), m_base(base)
+        : node(position), m_base(base)
     {
     }
 
@@ -362,7 +379,7 @@ namespace elna::frontend
 
     record_type_expression::record_type_expression(const struct position position,
             std::vector<field_declaration>&& fields)
-        : type_expression(position), fields(std::move(fields))
+        : node(position), fields(std::move(fields))
     {
     }
 
@@ -386,7 +403,7 @@ namespace elna::frontend
 
     union_type_expression::union_type_expression(const struct position position,
             std::vector<field_declaration>&& fields)
-        : type_expression(position), fields(std::move(fields))
+        : node(position), fields(std::move(fields))
     {
     }
 
@@ -464,7 +481,7 @@ namespace elna::frontend
     }
 
     procedure_type_expression::procedure_type_expression(const struct position position, return_t return_type)
-        : type_expression(position), return_type(return_type)
+        : node(position), return_type(return_type)
     {
     }
 
@@ -491,7 +508,7 @@ namespace elna::frontend
     }
 
     enumeration_type_expression::enumeration_type_expression(const struct position position, std::vector<std::string>&& members)
-        : type_expression(position), members(members)
+        : node(position), members(members)
     {
     }
 
@@ -559,6 +576,11 @@ namespace elna::frontend
     {
     }
 
+    block::block(std::vector<constant_declaration*>&& constants, std::vector<variable_declaration *>&& variables)
+        : m_variables(std::move(variables)), m_constants(std::move(constants))
+    {
+    }
+
     block::block(block&& that)
         : m_variables(std::move(that.m_variables)), m_constants(std::move(that.m_constants)),
         m_body(std::move(that.m_body))
@@ -657,10 +679,6 @@ namespace elna::frontend
         }
     }
 
-    literal_expression::literal_expression()
-    {
-    }
-
     literal_expression *literal_expression::is_literal()
     {
         return this;
@@ -684,10 +702,6 @@ namespace elna::frontend
         }
     }
 
-    designator_expression::designator_expression()
-    {
-    }
-
     designator_expression::~designator_expression()
     {
     }
@@ -699,7 +713,7 @@ namespace elna::frontend
 
     void designator_expression::accept(parser_visitor *visitor)
     {
-        if (variable_expression *node = is_variable())
+        if (named_expression *node = is_named())
         {
             return visitor->visit(node);
         }
@@ -718,17 +732,17 @@ namespace elna::frontend
         __builtin_unreachable();
     }
 
-    variable_expression::variable_expression(const struct position position, const std::string& name)
+    named_expression::named_expression(const struct position position, const std::string& name)
         : node(position), name(name)
     {
     }
 
-    void variable_expression::accept(parser_visitor *visitor)
+    void named_expression::accept(parser_visitor *visitor)
     {
         visitor->visit(this);
     }
 
-    variable_expression *variable_expression::is_variable()
+    named_expression *named_expression::is_named()
     {
         return this;
     }
@@ -1039,7 +1053,7 @@ namespace elna::frontend
         visitor->visit(this);
     }
 
-    variable_expression *designator_expression::is_variable()
+    named_expression *designator_expression::is_named()
     {
         return nullptr;
     }
diff --git a/frontend/lexer.ll b/frontend/lexer.ll
index f14497b..7c18b32 100644
--- a/frontend/lexer.ll
+++ b/frontend/lexer.ll
@@ -130,12 +130,6 @@ or {
 return {
     return yy::parser::make_RETURN(this->location);
 }
-module {
-    return yy::parser::make_MODULE(this->location);
-}
-program {
-    return yy::parser::make_PROGRAM(this->location);
-}
 import {
     return yy::parser::make_IMPORT(this->location);
 }
diff --git a/frontend/parser.yy b/frontend/parser.yy
index bace8d7..5e3837b 100644
--- a/frontend/parser.yy
+++ b/frontend/parser.yy
@@ -102,8 +102,6 @@ along with GCC; see the file COPYING3.  If not see
     ELSE "else"
     ELSIF "elsif"
     RETURN "return"
-    PROGRAM "program"
-    MODULE "module"
     IMPORT "import"
     BEGIN_BLOCK "begin"
     END_BLOCK "end"
@@ -142,11 +140,12 @@ along with GCC; see the file COPYING3.  If not see
 %type <elna::frontend::procedure_call*> call_expression;
 %type <elna::frontend::return_statement *> return_statement;
 %type <elna::frontend::statement *> statement;
-%type <std::vector<elna::frontend::statement *>> required_statements optional_statements statement_part;
+%type <std::vector<elna::frontend::statement *>> required_statements optional_statements;
+%type <std::unique_ptr<std::vector<elna::frontend::statement *>>> statement_part;
 %type <elna::frontend::procedure_declaration *> procedure_declaration;
 %type <std::pair<std::vector<std::string>, elna::frontend::procedure_type_expression *>> procedure_heading;
 %type <elna::frontend::procedure_type_expression::return_t> return_declaration;
-%type <std::vector<elna::frontend::procedure_declaration *>> procedure_declarations procedure_part;
+%type <std::vector<elna::frontend::procedure_declaration *>> procedure_part;
 %type <elna::frontend::type_declaration *> type_declaration;
 %type <std::vector<elna::frontend::type_declaration *>> type_declarations type_part;
 %type <std::unique_ptr<elna::frontend::block>> block;
@@ -162,43 +161,47 @@ along with GCC; see the file COPYING3.  If not see
 %type <std::vector<elna::frontend::import_declaration *>> import_declarations import_part;
 %%
 program:
-    "program" ";" import_part constant_part type_part variable_part procedure_part statement_part "end" "."
+    import_part constant_part type_part variable_part procedure_part statement_part "end" "."
         {
-            auto tree = new frontend::program(frontend::make_position(@1));
-
-            std::swap(tree->imports, $3);
-            std::swap(tree->constants, $4);
-            std::swap(tree->types , $5);
-            std::swap(tree->variables, $6);
-            std::swap(tree->procedures, $7);
-            std::swap(tree->body, $8);
-
-            driver.tree.reset(tree);
-        }
-    | "module" ";" import_part constant_part type_part variable_part procedure_part "end" "."
-        {
-            auto tree = new frontend::unit(frontend::make_position(@1));
-
-            std::swap(tree->imports, $3);
-            std::swap(tree->constants, $4);
-            std::swap(tree->types , $5);
-            std::swap(tree->variables, $6);
-            std::swap(tree->procedures, $7);
+            if ($6)
+            {
+                frontend::program *tree = new frontend::program(frontend::make_position(@1));
+                std::swap(tree->body, *$6.release());
 
-            driver.tree.reset(tree);
+                driver.tree.reset(tree);
+            }
+            else
+            {
+                driver.tree.reset(new frontend::unit(frontend::make_position(@1)));
+            }
+            std::swap(driver.tree->imports, $1);
+            std::swap(driver.tree->constants, $2);
+            std::swap(driver.tree->types , $3);
+            std::swap(driver.tree->variables, $4);
+            std::swap(driver.tree->procedures, $5);
         }
 block: constant_part variable_part statement_part "end"
         {
-            $$ = std::make_unique<frontend::block>(std::move($1), std::move($2), std::move($3));
+            if ($3)
+            {
+                $$ = std::make_unique<frontend::block>(std::move($1), std::move($2), std::move(*$3.release()));
+            }
+            else
+            {
+                $$ = std::make_unique<frontend::block>(std::move($1), std::move($2));
+            }
         }
 statement_part:
     /* no statements */ {}
-    | "begin" required_statements { std::swap($$, $2); }
-    | return_statement { $$.push_back($1); }
+    | "begin" required_statements { $$ = std::make_unique<std::vector<frontend::statement *>>(std::move($2));; }
+    | return_statement
+        {
+            $$ = std::make_unique<std::vector<frontend::statement *>>(std::vector<frontend::statement *>{ $1 });
+        }
     | "begin" required_statements ";" return_statement
         {
-            std::swap($$, $2);
-            $$.push_back($4);
+            $$ = std::make_unique<std::vector<frontend::statement *>>(std::move($2));
+            $$->push_back($4);
         }
 identifier_definition:
     IDENTIFIER "*" { $$ = frontend::identifier_definition{ $1, true }; }
@@ -224,26 +227,24 @@ procedure_heading: formal_parameter_list return_declaration
             }
         }
 procedure_declaration:
-    "proc" identifier_definition procedure_heading ";" block ";"
+    "proc" identifier_definition procedure_heading block
         {
-            $$ = new frontend::procedure_declaration(frontend::make_position(@1), std::move($2), $3.second, std::move(*$5));
+            $$ = new frontend::procedure_declaration(frontend::make_position(@1), std::move($2), $3.second,
+                    std::move(*$4));
             std::swap($3.first, $$->parameter_names);
         }
-    | "proc" identifier_definition procedure_heading ";" "extern" ";"
+    | "proc" identifier_definition procedure_heading "extern"
         {
             $$ = new frontend::procedure_declaration(frontend::make_position(@1), std::move($2), $3.second);
             std::swap($3.first, $$->parameter_names);
         }
-procedure_declarations:
-    procedure_declaration procedure_declarations
+procedure_part:
+    /* no procedure declarations */ {}
+    | procedure_declaration procedure_part
         {
             std::swap($$, $2);
             $$.emplace($$.cbegin(), std::move($1));
         }
-    | procedure_declaration { $$.emplace_back(std::move($1)); }
-procedure_part:
-    /* no procedure definitions */ {}
-    | procedure_declarations { std::swap($$, $1); }
 call_expression: designator_expression actual_parameter_list
         {
             $$ = new frontend::procedure_call(frontend::make_position(@1), $1);
@@ -401,7 +402,7 @@ designator_expression:
     | simple_expression "^"
         { $$ = new frontend::dereference_expression(frontend::make_position(@1), $1); }
     | IDENTIFIER
-        { $$ = new frontend::variable_expression(frontend::make_position(@1), $1); }
+        { $$ = new frontend::named_expression(frontend::make_position(@1), $1); }
 statement:
     designator_expression ":=" expression
         { $$ = new frontend::assign_statement(frontend::make_position(@1), $1, $3); }
@@ -487,7 +488,7 @@ type_expression:
         }
     | IDENTIFIER
         {
-            $$ = new frontend::named_type_expression(frontend::make_position(@1), $1);
+            $$ = new frontend::named_expression(frontend::make_position(@1), $1);
         }
 identifiers:
     IDENTIFIER "," identifiers
@@ -497,18 +498,18 @@ identifiers:
         }
     | IDENTIFIER { $$.emplace_back(std::move($1)); }
 variable_declaration:
-    identifier_definitions ":" type_expression ";"
+    identifier_definitions ":" type_expression
         {
             std::shared_ptr<frontend::type_expression> shared_type{ $3 };
             $$ = new frontend::variable_declaration( frontend::make_position(@2), std::move($1), shared_type);
         }
-    | identifier_definitions ":" type_expression ":=" "extern" ";"
+    | identifier_definitions ":" type_expression ":=" "extern"
         {
             std::shared_ptr<frontend::type_expression> shared_type{ $3 };
             $$ = new frontend::variable_declaration( frontend::make_position(@2), std::move($1), shared_type,
                 std::monostate{});
         }
-    | identifier_definitions ":" type_expression ":=" expression ";"
+    | identifier_definitions ":" type_expression ":=" expression
         {
             std::shared_ptr<frontend::type_expression> shared_type{ $3 };
             $$ = new frontend::variable_declaration( frontend::make_position(@2), std::move($1), shared_type, $5);
@@ -523,7 +524,7 @@ variable_declarations:
 variable_part:
     /* no variable declarations */ {}
     | "var" variable_declarations { std::swap($$, $2); }
-constant_declaration: identifier_definition ":=" expression ";"
+constant_declaration: identifier_definition ":=" expression
         {
             $$ = new frontend::constant_declaration(frontend::make_position(@1), std::move($1), $3);
         }
@@ -556,8 +557,8 @@ import_declarations:
         }
 import_part:
     /* no import declarations */ {}
-    | "import" import_declarations ";" { std::swap($$, $2); }
-type_declaration: identifier_definition "=" type_expression ";"
+    | "import" import_declarations { std::swap($$, $2); }
+type_declaration: identifier_definition "=" type_expression
         {
             $$ = new frontend::type_declaration(frontend::make_position(@1), std::move($1), $3);
         }
diff --git a/frontend/semantic.cc b/frontend/semantic.cc
index 36c75b8..ee18492 100644
--- a/frontend/semantic.cc
+++ b/frontend/semantic.cc
@@ -223,10 +223,20 @@ namespace elna::frontend
     {
         visit(static_cast<unit *>(program));
 
+        this->bag.enter();
+        auto variable_type = this->bag.lookup("Int")->is_type()->symbol;
+        this->bag.enter("count", std::make_shared<variable_info>(variable_type, false));
+
+        variable_type = this->bag.lookup("Char")->is_type()->symbol;
+        variable_type = type(std::make_shared<pointer_type>(variable_type));
+        variable_type = type(std::make_shared<pointer_type>(variable_type));
+        this->bag.enter("parameters", std::make_shared<variable_info>(variable_type, false));
+
         for (statement *const statement : program->body)
         {
             statement->accept(this);
         }
+        this->bag.leave();
     }
 
     void name_analysis_visitor::visit(type_declaration *definition)
@@ -239,23 +249,8 @@ namespace elna::frontend
         this->bag.enter(definition->identifier.name, info);
     }
 
-    void name_analysis_visitor::visit(named_type_expression *type_expression)
+    void name_analysis_visitor::visit(type_expression *)
     {
-        auto unresolved_alias = this->bag.declared(type_expression->name);
-
-        if (unresolved_alias != nullptr)
-        {
-            this->current_type = type(unresolved_alias);
-        }
-        else if (auto from_symbol_table = this->bag.lookup(type_expression->name))
-        {
-            this->current_type = from_symbol_table->is_type()->symbol;
-        }
-        else
-        {
-            add_error<undeclared_error>(type_expression->name, this->input_file, type_expression->position());
-            this->current_type = type();
-        }
     }
 
     void name_analysis_visitor::visit(pointer_type_expression *type_expression)
@@ -267,7 +262,9 @@ namespace elna::frontend
     void name_analysis_visitor::visit(array_type_expression *type_expression)
     {
         type_expression->base().accept(this);
-        this->current_type = type(std::make_shared<array_type>(this->current_type, type_expression->size));
+        auto result_type{ std::make_shared<array_type>(this->current_type, type_expression->size) };
+
+        this->current_type = type(result_type);
     }
 
     std::vector<type_field> name_analysis_visitor::build_composite_type(const std::vector<field_declaration>& fields)
@@ -324,20 +321,27 @@ namespace elna::frontend
         this->current_type = type(result_type);
     }
 
+    std::shared_ptr<variable_info> name_analysis_visitor::register_variable(const std::string& name,
+            const bool is_extern, const struct position position)
+    {
+        auto variable_symbol = std::make_shared<variable_info>(this->current_type, is_extern);
+
+        if (!this->bag.enter(name, variable_symbol))
+        {
+            add_error<already_declared_error>(name, this->input_file, position);
+        }
+        return variable_symbol;
+    }
+
     void name_analysis_visitor::visit(variable_declaration *declaration)
     {
         declaration->variable_type().accept(this);
 
         for (const auto& variable_identifier : declaration->identifiers)
         {
-            auto variable_symbol = std::make_shared<variable_info>(this->current_type, declaration->is_extern);
-
+            auto variable_symbol = register_variable(variable_identifier.name, declaration->is_extern,
+                    declaration->position());
             variable_symbol->exported = variable_identifier.exported;
-            if (!this->bag.enter(variable_identifier.name, variable_symbol))
-            {
-                add_error<already_declared_error>(variable_identifier.name, this->input_file,
-                        declaration->position());
-            }
         }
     }
 
@@ -358,7 +362,19 @@ namespace elna::frontend
         if (definition->body.has_value())
         {
             info = std::make_shared<procedure_info>(heading, definition->parameter_names, this->bag.enter());
+            auto name_iterator = std::cbegin(definition->parameter_names);
+            auto type_iterator = std::cbegin(heading.parameters);
 
+            while (name_iterator != std::cend(definition->parameter_names)
+                    && type_iterator != std::cend(heading.parameters))
+            {
+                this->current_type = *type_iterator;
+                auto variable_symbol = register_variable(*name_iterator, false, definition->heading().position());
+                variable_symbol->exported = false;
+
+                ++name_iterator;
+                ++type_iterator;
+            }
             for (constant_declaration *const constant : definition->body.value().constants())
             {
                 constant->accept(this);
@@ -489,6 +505,10 @@ namespace elna::frontend
         {
             variable->accept(this);
         }
+        for (constant_declaration *const constant : unit->constants)
+        {
+            constant->accept(this);
+        }
         for (procedure_declaration *const procedure : unit->procedures)
         {
             procedure->accept(this);
@@ -522,8 +542,26 @@ namespace elna::frontend
         expression->operand().accept(this);
     }
 
-    void name_analysis_visitor::visit(variable_expression *)
+    void name_analysis_visitor::visit(named_expression *type_expression)
     {
+        auto unresolved_alias = this->bag.declared(type_expression->name);
+
+        if (unresolved_alias != nullptr)
+        {
+            this->current_type = type(unresolved_alias);
+        }
+        else if (auto from_symbol_table = this->bag.lookup(type_expression->name))
+        {
+            if (auto type_symbol = from_symbol_table->is_type())
+            {
+                this->current_type = type_symbol->symbol;
+            }
+        }
+        else
+        {
+            add_error<undeclared_error>(type_expression->name, this->input_file, type_expression->position());
+            this->current_type = type();
+        }
     }
 
     void name_analysis_visitor::visit(array_access_expression *expression)
diff --git a/gcc/README.md b/gcc/README.md
index 99d03c3..14219d8 100644
--- a/gcc/README.md
+++ b/gcc/README.md
@@ -14,7 +14,7 @@ in the `boot/` directory.
 
 ## Build
 
-The frontend requires GCC 15.2.0 (not tested with other versions).
+The frontend requires GCC 15.3.0 (not tested with other versions).
 
 Download the GCC source. Copy the contents of this repository into `gcc/elna`
 inside GCC. Finally build GCC enabling the frontend with
diff --git a/gcc/elna-generic.cc b/gcc/elna-generic.cc
index b37b111..a5aa5f5 100644
--- a/gcc/elna-generic.cc
+++ b/gcc/elna-generic.cc
@@ -169,7 +169,7 @@ namespace elna::gcc
     {
         location_t call_location = get_location(&call->position());
 
-        if (frontend::variable_expression *named_call = call->callable().is_variable())
+        if (frontend::named_expression *named_call = call->callable().is_named())
         {
             if (named_call->name == "assert")
             {
@@ -784,7 +784,7 @@ namespace elna::gcc
         }
     }
 
-    void generic_visitor::visit(frontend::variable_expression *expression)
+    void generic_visitor::visit(frontend::named_expression *expression)
     {
         auto symbol = this->symbols->lookup(expression->name);
 
@@ -1023,7 +1023,7 @@ namespace elna::gcc
         if (TREE_CODE(lvalue) == CONST_DECL)
         {
             error_at(statement_location, "Cannot modify constant '%s'",
-                    statement->lvalue().is_variable()->name.c_str());
+                    statement->lvalue().is_named()->name.c_str());
         }
         else if (TYPE_READONLY(TREE_TYPE(lvalue)))
         {
diff --git a/include/elna/frontend/ast.h b/include/elna/frontend/ast.h
index bbb8a36..0b5f3d7 100644
--- a/include/elna/frontend/ast.h
+++ b/include/elna/frontend/ast.h
@@ -71,14 +71,14 @@ namespace elna::frontend
     class program;
     class binary_expression;
     class unary_expression;
-    class named_type_expression;
+    class type_expression;
     class array_type_expression;
     class pointer_type_expression;
     class record_type_expression;
     class union_type_expression;
     class procedure_type_expression;
     class enumeration_type_expression;
-    class variable_expression;
+    class named_expression;
     class array_access_expression;
     class field_access_expression;
     class dereference_expression;
@@ -111,14 +111,14 @@ namespace elna::frontend
         virtual void visit(program *) = 0;
         virtual void visit(binary_expression *) = 0;
         virtual void visit(unary_expression *) = 0;
-        virtual void visit(named_type_expression *) = 0;
+        virtual void visit(type_expression *) = 0;
         virtual void visit(array_type_expression *) = 0;
         virtual void visit(pointer_type_expression *) = 0;
         virtual void visit(record_type_expression *) = 0;
         virtual void visit(union_type_expression *) = 0;
         virtual void visit(procedure_type_expression *) = 0;
         virtual void visit(enumeration_type_expression *) = 0;
-        virtual void visit(variable_expression *) = 0;
+        virtual void visit(named_expression *) = 0;
         virtual void visit(array_access_expression *) = 0;
         virtual void visit(field_access_expression *) = 0;
         virtual void visit(dereference_expression *) = 0;
@@ -139,7 +139,7 @@ namespace elna::frontend
         [[noreturn]] void not_implemented();
 
     public:
-        [[noreturn]] virtual void visit(named_type_expression *) override;
+        [[noreturn]] virtual void visit(type_expression *) override;
         [[noreturn]] virtual void visit(array_type_expression *) override;
         [[noreturn]] virtual void visit(pointer_type_expression *) override;
         [[noreturn]] virtual void visit(program *) override;
@@ -165,7 +165,7 @@ namespace elna::frontend
         [[noreturn]] virtual void visit(traits_expression *) override;
         [[noreturn]] virtual void visit(binary_expression *) override;
         [[noreturn]] virtual void visit(unary_expression *) override;
-        [[noreturn]] virtual void visit(variable_expression *) override;
+        [[noreturn]] virtual void visit(named_expression *) override;
         [[noreturn]] virtual void visit(array_access_expression *) override;
         [[noreturn]] virtual void visit(field_access_expression *) override;
         [[noreturn]] virtual void visit(dereference_expression *) override;
@@ -232,10 +232,10 @@ namespace elna::frontend
     /**
      * Some type expression.
      */
-    class type_expression : public node
+    class type_expression : public virtual node
     {
     public:
-        virtual named_type_expression *is_named();
+        virtual named_expression *is_named();
         virtual array_type_expression *is_array();
         virtual pointer_type_expression *is_pointer();
         virtual record_type_expression *is_record();
@@ -243,21 +243,8 @@ namespace elna::frontend
         virtual procedure_type_expression *is_procedure();
         virtual enumeration_type_expression *is_enumeration();
 
-    protected:
-        type_expression(const struct position position);
-    };
-
-    /**
-     * Expression refering to a type by its name.
-     */
-    class named_type_expression : public type_expression
-    {
-    public:
-        const std::string name;
-
-        named_type_expression(const struct position position, const std::string& name);
         void accept(parser_visitor *visitor) override;
-        named_type_expression *is_named() override;
+        ~type_expression() = 0;
     };
 
     class array_type_expression : public type_expression
@@ -363,9 +350,6 @@ namespace elna::frontend
     {
     public:
         literal_expression *is_literal() override;
-
-    protected:
-        literal_expression();
     };
 
     /**
@@ -407,6 +391,7 @@ namespace elna::frontend
     {
         block(std::vector<constant_declaration*>&& constants, std::vector<variable_declaration *>&& variables,
                 std::vector<statement *>&& body);
+        block(std::vector<constant_declaration*>&& constants, std::vector<variable_declaration *>&& variables);
         block(const block&) = delete;
         block(block&& that);
 
@@ -553,7 +538,7 @@ namespace elna::frontend
     class designator_expression : public expression
     {
     public:
-        virtual variable_expression *is_variable();
+        virtual named_expression *is_named();
         virtual array_access_expression *is_array_access();
         virtual field_access_expression *is_field_access();
         virtual dereference_expression *is_dereference();
@@ -561,20 +546,20 @@ namespace elna::frontend
         designator_expression *is_designator() override;
         void accept(parser_visitor *visitor);
         ~designator_expression() = 0;
-
-    protected:
-        designator_expression();
     };
 
-    class variable_expression : public designator_expression, public literal_expression
+    /**
+     * Expression refering to an entity by its name.
+     */
+    class named_expression : public designator_expression, public type_expression
     {
     public:
         const std::string name;
 
-        variable_expression(const struct position position, const std::string& name);
+        named_expression(const struct position position, const std::string& name);
         void accept(parser_visitor *visitor) override;
 
-        variable_expression *is_variable() override;
+        named_expression *is_named() override;
     };
 
     class array_access_expression : public designator_expression
diff --git a/include/elna/frontend/semantic.h b/include/elna/frontend/semantic.h
index 8a295e4..887b660 100644
--- a/include/elna/frontend/semantic.h
+++ b/include/elna/frontend/semantic.h
@@ -127,11 +127,13 @@ namespace elna::frontend
 
         procedure_type build_procedure(procedure_type_expression& type_expression);
         std::vector<type_field> build_composite_type(const std::vector<field_declaration>& fields);
+        std::shared_ptr<variable_info> register_variable(const std::string& name,
+                const bool is_extern, const struct position position);
 
     public:
         name_analysis_visitor(const char *path, symbol_bag bag);
 
-        void visit(named_type_expression *type_expression) override;
+        void visit(type_expression *) override;
         void visit(array_type_expression *type_expression) override;
         void visit(pointer_type_expression *type_expression) override;
         void visit(program *program) override;
@@ -157,7 +159,7 @@ namespace elna::frontend
         void visit(traits_expression *trait) override;
         void visit(binary_expression *expression) override;
         void visit(unary_expression *expression) override;
-        void visit(variable_expression *) override;
+        void visit(named_expression *type_expression) override;
         void visit(array_access_expression *expression) override;
         void visit(field_access_expression *expression) override;
         void visit(dereference_expression *expression) override;
diff --git a/include/elna/gcc/elna-generic.h b/include/elna/gcc/elna-generic.h
index 97cd512..ec6f32f 100644
--- a/include/elna/gcc/elna-generic.h
+++ b/include/elna/gcc/elna-generic.h
@@ -81,7 +81,7 @@ namespace elna::gcc
         void visit(frontend::unary_expression *expression) override;
         void visit(frontend::constant_declaration *definition) override;
         void visit(frontend::variable_declaration *declaration) override;
-        void visit(frontend::variable_expression *expression) override;
+        void visit(frontend::named_expression *expression) override;
         void visit(frontend::array_access_expression *expression) override;
         void visit(frontend::field_access_expression *expression) override;
         void visit(frontend::dereference_expression *expression) override;
diff --git a/rakelib/gcc.rake b/rakelib/gcc.rake
index 39b4442..2b8bbfb 100644
--- a/rakelib/gcc.rake
+++ b/rakelib/gcc.rake
@@ -10,7 +10,7 @@ require 'pathname'
 
 def gcc_verbose(gcc_binary)
   read, write = IO.pipe
-  sh({'LANG' => 'C'}, gcc_binary, '--verbose', err: write)
+  sh({'LC_ALL' => 'C'}, gcc_binary, '--verbose', err: write)
   write.close
   output = read.read
   read.close
@@ -60,10 +60,10 @@ end
 
 namespace :gcc do
   # Dependencies.
-  GCC_VERSION = "15.2.0"
+  GCC_VERSION = "15.3.0"
   HOST_GCC = 'build/host/gcc'
   HOST_INSTALL = 'build/host/install'
-  GCC_PATCH = 'https://raw.githubusercontent.com/Homebrew/formula-patches/575ffcaed6d3112916fed77d271dd3799a7255c4/gcc/gcc-15.1.0.diff'
+  GCC_PATCH = 'https://raw.githubusercontent.com/Homebrew/homebrew-core/refs/heads/main/Patches/gcc/gcc-15.3.0.diff'
 
   directory HOST_GCC
   directory HOST_INSTALL
diff --git a/source/cctype.elna b/source/cctype.elna
index 3906cd1..13dc50a 100644
--- a/source/cctype.elna
+++ b/source/cctype.elna
@@ -1,14 +1,23 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
-proc isdigit*(c: Int ) -> Int; extern;
-proc isalnum*(c: Int) -> Int; extern;
-proc isalpha*(c: Int) -> Int; extern;
-proc isspace*(c: Int) -> Int; extern;
+proc isdigit*(c: Int ) -> Int
+extern
 
-proc tolower*(c: Int) -> Int; extern;
-proc toupper*(c: Int) -> Int; extern;
+proc isalnum*(c: Int) -> Int
+extern
+
+proc isalpha*(c: Int) -> Int
+extern
+
+proc isspace*(c: Int) -> Int
+extern
+
+proc tolower*(c: Int) -> Int
+extern
+
+proc toupper*(c: Int) -> Int
+extern
 
 end.
diff --git a/source/command_line_interface.elna b/source/command_line_interface.elna
index 040fdeb..78e1cf5 100644
--- a/source/command_line_interface.elna
+++ b/source/command_line_interface.elna
@@ -5,9 +5,7 @@
 (*
   Command line handling.
 *)
-module;
-
-import cstdlib, cstring, common;
+import cstdlib, cstring, common
 
 type
   CommandLine* = record
@@ -15,14 +13,14 @@ type
     output: ^Char;
     lex: Bool;
     parse: Bool
-  end;
+  end
 
-proc parse_command_line*(argc: Int, argv: ^^Char) -> ^CommandLine;
+proc parse_command_line*(argc: Int, argv: ^^Char) -> ^CommandLine
 var
-  parameter: ^Char;
-  i: Int;
-  result: ^CommandLine;
-  parsed: Bool;
+  parameter: ^Char
+  i: Int
+  result: ^CommandLine
+  parsed: Bool
 begin
   i := 1;
   result := cast(malloc(#size(CommandLine)): ^CommandLine);
@@ -88,6 +86,6 @@ begin
   end;
 
   return result
-end;
+end
 
 end.
diff --git a/source/common.elna b/source/common.elna
index e7b30ca..33a79b8 100644
--- a/source/common.elna
+++ b/source/common.elna
@@ -1,50 +1,50 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
-import cstring, cstdio;
+import cstring, cstdio
 
 type
-  Identifier = [256]Char;
+  Identifier = [256]Char
   TextLocation* = record
     line: Word;
     column: Word
-  end;
+  end
 
-proc write*(fd: Int, buf: Pointer, Word: Int) -> Int; extern;
+proc write*(fd: Int, buf: Pointer, Word: Int) -> Int
+extern
 
-proc write_s*(value: String);
+proc write_s*(value: String)
 begin
   (* fwrite(cast(value.ptr: Pointer), value.length, 1u, stdout) *)
   write(1, cast(value.ptr: Pointer), cast(value.length: Int))
-end;
+end
 
-proc write_z*(value: ^Char);
+proc write_z*(value: ^Char)
 begin
   write(1, cast(value: Pointer), cast(strlen(value): Int))
-end;
+end
 
-proc write_b*(value: Bool);
+proc write_b*(value: Bool)
 begin
   if value then
     write_s("true")
   else
     write_s("false")
   end
-end;
+end
 
-proc write_c*(value: Char);
+proc write_c*(value: Char)
 begin
   putchar(cast(value: Int));
   fflush(nil)
-end;
+end
 
-proc write_i*(value: Int);
+proc write_i*(value: Int)
 var
-  digit: Int;
-  n: Word;
-  buffer: [10]Char;
+  digit: Int
+  n: Word
+  buffer: [10]Char
 begin
   n := 10u;
 
@@ -62,11 +62,11 @@ begin
     n := n + 1u;
     write_c(buffer[n])
   end
-end;
+end
 
-proc write_u*(value: Word);
+proc write_u*(value: Word)
 begin
   write_i(cast(value: Int))
-end;
+end
 
 end.
diff --git a/source/cstdio.elna b/source/cstdio.elna
index c7507ff..b86014f 100644
--- a/source/cstdio.elna
+++ b/source/cstdio.elna
@@ -1,29 +1,46 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
 type
-  FILE* = record end;
+  FILE* = record end
 
 var
-  stdin*: ^FILE := extern;
-  stdout*: ^FILE := extern;
-  stderr*: ^FILE := extern;
+  stdin*: ^FILE := extern
+  stdout*: ^FILE := extern
+  stderr*: ^FILE := extern
 
-proc fopen*(pathname: ^Char, mode: ^Char) -> ^FILE; extern;
-proc fclose*(stream: ^FILE) -> Int; extern;
-proc fseek*(stream: ^FILE, off: Int, whence: Int) -> Int; extern;
-proc rewind*(stream: ^FILE); extern;
-proc ftell*(stream: ^FILE) -> Int; extern;
-proc fflush*(stream: ^FILE) -> Int; extern;
+proc fopen*(pathname: ^Char, mode: ^Char) -> ^FILE
+extern
 
-proc fread*(ptr: Pointer, size: Word, nmemb: Word, stream: ^FILE) -> Word; extern;
-proc fwrite*(ptr: Pointer, size: Word, nitems: Word, stream: ^FILE) -> Word; extern;
+proc fclose*(stream: ^FILE) -> Int
+extern
 
-proc perror(s: ^Char); extern;
+proc fseek*(stream: ^FILE, off: Int, whence: Int) -> Int
+extern
 
-proc puts(s: ^Char) -> Int; extern;
-proc putchar(c: Int) -> Int; extern;
+proc rewind*(stream: ^FILE)
+extern
+
+proc ftell*(stream: ^FILE) -> Int
+extern
+
+proc fflush*(stream: ^FILE) -> Int
+extern
+
+proc fread*(ptr: Pointer, size: Word, nmemb: Word, stream: ^FILE) -> Word
+extern
+
+proc fwrite*(ptr: Pointer, size: Word, nitems: Word, stream: ^FILE) -> Word
+extern
+
+proc perror(s: ^Char)
+extern
+
+proc puts(s: ^Char) -> Int
+extern
+
+proc putchar(c: Int) -> Int
+extern
 
 end.
diff --git a/source/cstdlib.elna b/source/cstdlib.elna
index da2029c..3346440 100644
--- a/source/cstdlib.elna
+++ b/source/cstdlib.elna
@@ -1,15 +1,23 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
-proc malloc(size: Word) -> Pointer; extern;
-proc free(ptr: Pointer); extern;
-proc calloc(nmemb: Word, size: Word) -> Pointer; extern;
-proc realloc(ptr: Pointer, size: Word) -> Pointer; extern;
+proc malloc(size: Word) -> Pointer
+extern
 
-proc atoi(str: ^Char) -> Int; extern;
+proc free(ptr: Pointer)
+extern
 
-proc exit(code: Int) -> !; extern;
+proc calloc(nmemb: Word, size: Word) -> Pointer
+extern
+
+proc realloc(ptr: Pointer, size: Word) -> Pointer
+extern
+
+proc atoi(str: ^Char) -> Int
+extern
+
+proc exit(code: Int) -> !
+extern
 
 end.
diff --git a/source/cstring.elna b/source/cstring.elna
index 24d852a..ef04e59 100644
--- a/source/cstring.elna
+++ b/source/cstring.elna
@@ -1,15 +1,26 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
-proc memset(ptr: Pointer, c: Int, n: Word) -> ^Char; extern;
-proc memcpy(dst: Pointer, src: Pointer, n: Word); extern;
+proc memset(ptr: Pointer, c: Int, n: Word) -> ^Char
+extern
 
-proc strcmp(s1: ^Char, s2: ^Char) -> Int; extern;
-proc strncmp(s1: ^Char, s2: ^Char, n: Word) -> Int; extern;
-proc strncpy(dst: ^Char, src: ^Char, dsize: Word) -> ^Char; extern;
-proc strcpy(dst: ^Char, src: ^Char) -> ^Char; extern;
-proc strlen(ptr: ^Char) -> Word; extern;
+proc memcpy(dst: Pointer, src: Pointer, n: Word)
+extern
+
+proc strcmp(s1: ^Char, s2: ^Char) -> Int
+extern
+
+proc strncmp(s1: ^Char, s2: ^Char, n: Word) -> Int
+extern
+
+proc strncpy(dst: ^Char, src: ^Char, dsize: Word) -> ^Char
+extern
+
+proc strcpy(dst: ^Char, src: ^Char) -> ^Char
+extern
+
+proc strlen(ptr: ^Char) -> Word
+extern
 
 end.
diff --git a/source/lexer.elna b/source/lexer.elna
index d5f529b..e6fc38c 100644
--- a/source/lexer.elna
+++ b/source/lexer.elna
@@ -1,12 +1,11 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-module;
 
-import cstdio, cstring, cctype, cstdlib, common;
+import cstdio, cstring, cctype, cstdlib, common
 
 const
-  CHUNK_SIZE := 85536u;
+  CHUNK_SIZE := 85536u
 
 type
   (*
@@ -38,7 +37,7 @@ type
     greater,
     less,
     other
-  );
+  )
   TransitionState = (
     start,
     colon,
@@ -56,7 +55,7 @@ type
     leading_zero,
     decimal_suffix,
     finish
-  );
+  )
   LexerToken = record
     kind: LexerKind;
     value: union
@@ -67,18 +66,18 @@ type
     end;
     start_location: TextLocation;
     end_location: TextLocation
-  end;
-  TransitionAction = proc(^Lexer, ^LexerToken);
+  end
+  TransitionAction = proc(^Lexer, ^LexerToken)
   Transition = record
     action: TransitionAction;
     next_state: TransitionState
-  end;
-  TransitionClasses = [22]Transition;
+  end
+  TransitionClasses = [22]Transition
 
   BufferPosition* = record
     iterator: ^Char;
     location: TextLocation
-  end;
+  end
   Lexer* = record
     input: ^FILE;
     buffer: ^Char;
@@ -86,7 +85,7 @@ type
     length: Word;
     start: BufferPosition;
     current: BufferPosition
-  end;
+  end
   LexerKind* = (
     unknown,
     identifier,
@@ -153,15 +152,15 @@ type
     _program,
     _module,
     _import
-  );
+  )
 
 var
-  classification: [128]TransitionClass;
-  transitions: [16]TransitionClasses;
+  classification: [128]TransitionClass
+  transitions: [16]TransitionClasses
 
-proc initialize_classification();
+proc initialize_classification()
 var
-  i: Word;
+  i: Word
 begin
   classification[1] := TransitionClass.eof; (* NUL *)
   classification[2] := TransitionClass.invalid; (* SOH *)
@@ -297,13 +296,13 @@ begin
     classification[i] := TransitionClass.other;
     i := i + 1u
   end
-end;
+end
 
-proc compare_keyword(keyword: String, token_start: BufferPosition, token_end: ^Char) -> Bool;
+proc compare_keyword(keyword: String, token_start: BufferPosition, token_end: ^Char) -> Bool
 var
-  result: Bool;
-  index: Word;
-  continue: Bool;
+  result: Bool
+  index: Word
+  continue: Bool
 begin
   index := 0u;
   result := true;
@@ -319,28 +318,28 @@ begin
   result := result & index = keyword.length;
 
   return result & (token_start.iterator = token_end)
-end;
+end
 
 (* Reached the end of file. *)
-proc transition_action_eof(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_eof(lexer: ^Lexer, token: ^LexerToken)
 begin
   token^.kind := LexerKind.unknown
-end;
+end
 
-proc increment(position: ^BufferPosition);
+proc increment(position: ^BufferPosition)
 begin
   position^.iterator := position^.iterator + 1
-end;
+end
 
 (* Add the character to the token currently read and advance to the next character. *)
-proc transition_action_accumulate(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_accumulate(lexer: ^Lexer, token: ^LexerToken)
 begin
   increment(@lexer^.current)
-end;
+end
 
 (* The current character is not a part of the token. Finish the token already
  * read. Don't advance to the next character. *)
-proc transition_action_finalize(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_finalize(lexer: ^Lexer, token: ^LexerToken)
 begin
   if lexer^.start.iterator^ = ':' then
     token^.kind := LexerKind.colon
@@ -360,10 +359,10 @@ begin
   if lexer^.start.iterator^ = '.' then
     token^.kind := LexerKind.dot
   end
-end;
+end
 
 (* An action for tokens containing multiple characters. *)
-proc transition_action_composite(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_composite(lexer: ^Lexer, token: ^LexerToken)
 begin
   if lexer^.start.iterator^ = '<' then
     if lexer^.current.iterator^ = '>' then
@@ -383,10 +382,10 @@ begin
     token^.kind := LexerKind.arrow
   end;
   increment(@lexer^.current)
-end;
+end
 
 (* Skip a space. *)
-proc transition_action_skip(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_skip(lexer: ^Lexer, token: ^LexerToken)
 begin
   increment(@lexer^.start);
 
@@ -395,12 +394,12 @@ begin
     lexer^.start.location.column := 1u
   end;
   lexer^.current := lexer^.start
-end;
+end
 
 (* Delimited string action. *)
-proc transition_action_delimited(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_delimited(lexer: ^Lexer, token: ^LexerToken)
 var
-  text_length: Word;
+  text_length: Word
 begin
   if lexer^.start.iterator^ = '(' then
     token^.kind := LexerKind.comment
@@ -422,10 +421,10 @@ begin
     token^.kind := LexerKind.string
   end;
   increment(@lexer^.current)
-end;
+end
 
 (* Finalize keyword or identifier. *)
-proc transition_action_key_id(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_key_id(lexer: ^Lexer, token: ^LexerToken)
 begin
   token^.kind := LexerKind.identifier;
 
@@ -515,11 +514,11 @@ begin
     token^.kind := LexerKind.boolean;
     token^.value.booleanKind := false
   end
-end;
+end
 
 (* Action for tokens containing only one character. The character cannot be
  * followed by other characters forming a composite token. *)
-proc transition_action_single(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_single(lexer: ^Lexer, token: ^LexerToken)
 begin
   if lexer^.current.iterator^ = '&' then
     token^.kind := LexerKind.and
@@ -567,14 +566,14 @@ begin
     token^.kind := LexerKind.pipe
   end;
   increment(@lexer^.current)
-end;
+end
 
 (* Handle an integer literal. *)
-proc transition_action_integer(lexer: ^Lexer, token: ^LexerToken);
+proc transition_action_integer(lexer: ^Lexer, token: ^LexerToken)
 var
-  buffer: String;
-  integer_length: Word;
-  found: Bool;
+  buffer: String
+  integer_length: Word
+  found: Bool
 begin
   token^.kind := LexerKind.integer;
 
@@ -584,12 +583,12 @@ begin
 
   token^.value.identifierKind[cast(token^.value.identifierKind[1]: Int) + 2] := '\0';
   token^.value.integerKind := atoi(@token^.value.identifierKind[2])
-end;
+end
 
-proc set_default_transition(current_state: TransitionState, default_action: TransitionAction, next_state: TransitionState) -> Int;
+proc set_default_transition(current_state: TransitionState, default_action: TransitionAction, next_state: TransitionState) -> Int
 var
-  default_transition: Transition;
-  state_index: Int;
+  default_transition: Transition
+  state_index: Int
 begin
   default_transition.action := default_action;
   default_transition.next_state := next_state;
@@ -619,7 +618,7 @@ begin
   transitions[state_index][cast(TransitionClass.other: Int) + 1] := default_transition;
 
   return state_index
-end;
+end
 
 (*
  * The transition table describes transitions from one state to another, given
@@ -637,9 +636,9 @@ end;
  *   For the meaning of actions see labels in the lex_next function, which
  *   handles each action.
  *)
-proc initialize_transitions();
+proc initialize_transitions()
 var
-  state_index: Int;
+  state_index: Int
 begin
   (* Start state. *)
   state_index := cast(TransitionState.start: Int) + 1;
@@ -877,9 +876,9 @@ begin
 
   transitions[state_index][cast(TransitionClass.x: Int) + 1].action := nil;
   transitions[state_index][cast(TransitionClass.x: Int) + 1].next_state := TransitionState.finish
-end;
+end
 
-proc lexer_make*(lexer: ^Lexer, input: ^FILE);
+proc lexer_make*(lexer: ^Lexer, input: ^FILE)
 begin
   lexer^.input := input;
   lexer^.length := 0u;
@@ -887,17 +886,17 @@ begin
   lexer^.buffer := cast(malloc(CHUNK_SIZE): ^Char);
   memset(cast(lexer^.buffer: Pointer), 0, CHUNK_SIZE);
   lexer^.size := CHUNK_SIZE
-end;
+end
 
 (* Returns the last read token. *)
-proc lexer_current*(lexer: ^Lexer) -> LexerToken;
+proc lexer_current*(lexer: ^Lexer) -> LexerToken
 var
-  current_class: TransitionClass;
-  current_state: TransitionState;
-  current_transition: Transition;
-  result: LexerToken;
-  index1: Word;
-  index2: Word;
+  current_class: TransitionClass
+  current_state: TransitionState
+  current_transition: Transition
+  result: LexerToken
+  index1: Word
+  index2: Word
 begin
   lexer^.current := lexer^.start;
   current_state := TransitionState.start;
@@ -919,12 +918,12 @@ begin
   result.end_location := lexer^.current.location;
 
   return result
-end;
+end
 
 (* Read and return the next token. *)
-proc lexer_lex*(lexer: ^Lexer) -> LexerToken;
+proc lexer_lex*(lexer: ^Lexer) -> LexerToken
 var
-  result: LexerToken;
+  result: LexerToken
 begin
   if lexer^.length = 0u then
     lexer^.length := fread(cast(lexer^.buffer: Pointer), CHUNK_SIZE, 1u, lexer^.input);
@@ -936,17 +935,17 @@ begin
 
   result := lexer_current(lexer);
   return result
-end;
+end
 
-proc lexer_destroy*(lexer: ^Lexer);
+proc lexer_destroy*(lexer: ^Lexer)
 begin
   free(cast(lexer^.buffer: Pointer))
-end;
+end
 
-proc lexer_initialize();
+proc lexer_initialize()
 begin
   initialize_classification();
   initialize_transitions()
-end;
+end
 
 end.
diff --git a/source/main.elna b/source/main.elna
index dae045b..e60f9ae 100644
--- a/source/main.elna
+++ b/source/main.elna
@@ -1,9 +1,8 @@
 (* This Source Code Form is subject to the terms of the Mozilla Public License,
   v. 2.0. If a copy of the MPL was not distributed with this file, You can
   obtain one at https://mozilla.org/MPL/2.0/. *)
-program;
 
-import cstdio, cctype, common, command_line_interface, lexer;
+import cstdio, cstdlib, cstring, cctype, common, command_line_interface, lexer
 
 type
   SourceFile* = record
@@ -11,12 +10,12 @@ type
     handle: ^FILE;
     size: Word;
     index: Word
-  end;
+  end
   StringBuffer* = record
     data: Pointer;
     size: Word;
     capacity: Word
-  end;
+  end
   SourceCode = record
     position: TextLocation;
 
@@ -24,7 +23,7 @@ type
     empty: proc(Pointer) -> Bool;
     advance: proc(Pointer);
     head: proc(Pointer) -> Char
-  end;
+  end
   Token* = record
     kind: LexerKind;
     value: union
@@ -33,49 +32,49 @@ type
       boolean_value: Bool;
       char_value: Char
     end
-  end;
+  end
   Tokenizer* = record
     length: Word;
     data: ^Token
-  end;
+  end
 
 (*
   Standard procedures.
 *)
-proc reallocarray(ptr: Pointer, n: Word, size: Word) -> Pointer;
+proc reallocarray(ptr: Pointer, n: Word, size: Word) -> Pointer
   return realloc(ptr, n * size)
-end;
+end
 
-proc substring(string: String, start: Word, count: Word) -> String;
+proc substring(string: String, start: Word, count: Word) -> String
   return String(string.ptr + start, count)
-end;
+end
 
-proc open_substring(string: String, start: Word) -> String;
+proc open_substring(string: String, start: Word) -> String
   return substring(string, start, string.length - start)
-end;
+end
 
-proc string_dup(origin: String) -> String;
+proc string_dup(origin: String) -> String
 var
-  copy: ^Char;
+  copy: ^Char
 begin
   copy := cast(malloc(origin.length): ^Char);
   strncpy(copy, origin.ptr, origin.length);
 
   return String(copy, origin.length)
-end;
+end
 
-proc string_buffer_new() -> StringBuffer;
+proc string_buffer_new() -> StringBuffer
 var
-  result: StringBuffer;
+  result: StringBuffer
 begin
   result.capacity := 64u;
   result.data := malloc(result.capacity);
   result.size := 0u;
 
   return result
-end;
+end
 
-proc string_buffer_push(buffer: ^StringBuffer, char: Char);
+proc string_buffer_push(buffer: ^StringBuffer, char: Char)
 begin
   if buffer^.size >= buffer^.capacity then
     buffer^.capacity := buffer^.capacity + 1024u;
@@ -83,30 +82,30 @@ begin
   end;
   cast(buffer^.data + buffer^.size: ^Char)^ := cast(char: Char);
   buffer^.size := buffer^.size + 1u
-end;
+end
 
-proc string_buffer_pop(buffer: ^StringBuffer, count: Word);
+proc string_buffer_pop(buffer: ^StringBuffer, count: Word)
 begin
   buffer^.size := buffer^.size - count
-end;
+end
 
-proc string_buffer_clear(buffer: ^StringBuffer) -> String;
+proc string_buffer_clear(buffer: ^StringBuffer) -> String
 var
-  result: String;
+  result: String
 begin
   result := String(cast(buffer^.data: ^Char), buffer^.size);
   buffer^.size := 0u;
   return result
-end;
+end
 
 (*
   Source code stream procedures.
 *)
 
-proc read_source(filename: ^Char) -> ^SourceFile;
+proc read_source(filename: ^Char) -> ^SourceFile
 var
-  result: ^SourceFile;
-  file_handle: ^FILE;
+  result: ^SourceFile
+  file_handle: ^FILE
 begin
   file_handle := fopen(filename, "rb\0".ptr);
 
@@ -117,11 +116,11 @@ begin
     result^.index := 1u
   end;
   return result
-end;
+end
 
-proc source_file_empty(source_input: Pointer) -> Bool;
+proc source_file_empty(source_input: Pointer) -> Bool
 var
-  source_file: ^SourceFile;
+  source_file: ^SourceFile
 begin
   source_file := cast(source_input: ^SourceFile);
 
@@ -131,57 +130,57 @@ begin
   end;
 
   return source_file^.size = 0u
-end;
+end
 
-proc source_file_head(source_input: Pointer) -> Char;
+proc source_file_head(source_input: Pointer) -> Char
 var
-  source_file: ^SourceFile;
+  source_file: ^SourceFile
 begin
   source_file := cast(source_input: ^SourceFile);
 
   return source_file^.buffer[source_file^.index]
-end;
+end
 
-proc source_file_advance(source_input: Pointer);
+proc source_file_advance(source_input: Pointer)
 var
-  source_file: ^SourceFile;
+  source_file: ^SourceFile
 begin
   source_file := cast(source_input: ^SourceFile);
 
   source_file^.index := source_file^.index + 1u
-end;
+end
 
-proc source_code_empty(source_code: ^SourceCode) -> Bool;
+proc source_code_empty(source_code: ^SourceCode) -> Bool
   return source_code^.empty(source_code^.input)
-end;
+end
 
-proc source_code_head(source_code: SourceCode) -> Char;
+proc source_code_head(source_code: SourceCode) -> Char
   return source_code.head(source_code.input)
-end;
+end
 
-proc source_code_advance(source_code: ^SourceCode);
+proc source_code_advance(source_code: ^SourceCode)
 begin
   source_code^.advance(source_code^.input);
   source_code^.position.column := source_code^.position.column
-end;
+end
 
-proc source_code_break(source_code: ^SourceCode);
+proc source_code_break(source_code: ^SourceCode)
 begin
   source_code^.position.line := source_code^.position.line + 1u;
   source_code^.position.column := 0u
-end;
+end
 
-proc source_code_expect(source_code: ^SourceCode, expected: Char) -> Bool;
+proc source_code_expect(source_code: ^SourceCode, expected: Char) -> Bool
   return ~source_code_empty(source_code) & source_code_head(source_code^) = expected
-end;
+end
 
 (*
   Token procedures.
 *)
 
-proc lexer_escape(escape: Char, result: ^Char) -> Bool;
+proc lexer_escape(escape: Char, result: ^Char) -> Bool
 var
-  successful: Bool;
+  successful: Bool
 begin
   case escape of
     'n':
@@ -224,12 +223,12 @@ begin
       successful := false
   end;
   return successful
-end;
+end
 
 (* Skip spaces. *)
-proc lexer_spaces(source_code: ^SourceCode);
+proc lexer_spaces(source_code: ^SourceCode)
 var
-  current: Char;
+  current: Char
 begin
   while ~source_code_empty(source_code) & isspace(cast(source_code_head(source_code^): Int)) <> 0 do
     current := source_code_head(source_code^);
@@ -239,26 +238,26 @@ begin
     end;
     source_code_advance(source_code)
   end
-end;
+end
 
 (* Checker whether the character is allowed in an identificator. *)
-proc lexer_is_ident(char: Char) -> Bool;
+proc lexer_is_ident(char: Char) -> Bool
   return isalnum(cast(char: Int)) <> 0 or char = '_'
-end;
+end
 
-proc lexer_identifier(source_code: ^SourceCode, token_content: ^StringBuffer);
+proc lexer_identifier(source_code: ^SourceCode, token_content: ^StringBuffer)
 var
-  content_length: Word;
+  content_length: Word
 begin
   while ~source_code_empty(source_code) & lexer_is_ident(source_code_head(source_code^)) do
     string_buffer_push(token_content, source_code_head(source_code^));
     source_code_advance(source_code)
   end
-end;
+end
 
-proc lexer_comment(source_code: ^SourceCode, token_content: ^StringBuffer) -> Bool;
+proc lexer_comment(source_code: ^SourceCode, token_content: ^StringBuffer) -> Bool
 var
-  trailing: Word;
+  trailing: Word
 begin
   trailing := 0u;
 
@@ -277,11 +276,11 @@ begin
   end;
 
   return trailing = 2u
-end;
+end
 
-proc lexer_character(source_code: ^SourceCode, token_content: ^Char) -> Bool;
+proc lexer_character(source_code: ^SourceCode, token_content: ^Char) -> Bool
 var
-  successful: Bool;
+  successful: Bool
 begin
   successful := ~source_code_empty(source_code);
 
@@ -299,14 +298,14 @@ begin
     source_code_advance(source_code)
   end;
   return successful
-end;
+end
 
-proc lexer_string(source_code: ^SourceCode, token_content: ^StringBuffer) -> Bool;
+proc lexer_string(source_code: ^SourceCode, token_content: ^StringBuffer) -> Bool
 var
-  token_end, constructed_string: ^Char;
-  token_length: Word;
-  is_valid: Bool := true;
-  next_char: Char;
+  token_end, constructed_string: ^Char
+  token_length: Word
+  is_valid: Bool := true
+  next_char: Char
 begin
   while is_valid & ~source_code_empty(source_code) & source_code_head(source_code^) <> '"' do
     is_valid := lexer_character(source_code, @next_char);
@@ -322,9 +321,9 @@ begin
     is_valid := false
   end;
   return is_valid
-end;
+end
 
-proc lexer_number(source_code: ^SourceCode, token_content: ^Int);
+proc lexer_number(source_code: ^SourceCode, token_content: ^Int)
 begin
   token_content^ := 0;
 
@@ -333,12 +332,12 @@ begin
 
     source_code_advance(source_code)
   end
-end;
+end
 
 (* Categorize an identifier. *)
-proc lexer_categorize(token_content: String) -> Token;
+proc lexer_categorize(token_content: String) -> Token
 var
-  current_token: Token;
+  current_token: Token
 begin
   if token_content = "if" then
     current_token.kind := LexerKind._if
@@ -402,23 +401,23 @@ begin
   end;
 
   return current_token
-end;
+end
 
-proc lexer_add_token(lexer: ^Tokenizer, token: Token);
+proc lexer_add_token(lexer: ^Tokenizer, token: Token)
 var
-  new_length: Word;
+  new_length: Word
 begin
   new_length := lexer^.length + 1u;
   lexer^.data := cast(reallocarray(cast(lexer^.data: Pointer), new_length, #size(Token)): ^Token);
   (lexer^.data + lexer^.length)^ := token;
   lexer^.length := new_length
-end;
+end
 
 (* Read the next token from the input. *)
-proc lexer_next(source_code: SourceCode, token_buffer: ^StringBuffer) -> Token;
+proc lexer_next(source_code: SourceCode, token_buffer: ^StringBuffer) -> Token
 var
-  current_token: Token;
-  first_char: Char;
+  current_token: Token
+  first_char: Char
 begin
   current_token.kind := LexerKind.unknown;
 
@@ -587,14 +586,14 @@ begin
   end;
 
   return current_token
-end;
+end
 
 (* Split the source text into tokens. *)
-proc lexer_text(source_code: SourceCode) -> Tokenizer;
+proc lexer_text(source_code: SourceCode) -> Tokenizer
 var
-  current_token: Token;
-  token_buffer: StringBuffer;
-  lexer: Tokenizer;
+  current_token: Token
+  token_buffer: StringBuffer
+  lexer: Tokenizer
 begin
   lexer := Tokenizer(0u, nil);
   token_buffer := string_buffer_new();
@@ -615,16 +614,16 @@ begin
   end;
 
   return lexer
-end;
+end
 
 (*
   Parser.
 *)
 
-proc parse(tokens: ^Token, tokens_size: Word);
+proc parse(tokens: ^Token, tokens_size: Word)
 var
-  current_token: ^Token;
-  i: Word := 0u;
+  current_token: ^Token
+  i: Word := 0u
 begin
   while i < tokens_size do
     current_token := tokens + i;
@@ -777,16 +776,16 @@ begin
     i := i + 1u
   end;
   write_c('\n')
-end;
+end
 
 (*
   Compilation entry.
 *)
 
-proc compile_in_stages(command_line: ^CommandLine, source_code: SourceCode) -> Int;
+proc compile_in_stages(command_line: ^CommandLine, source_code: SourceCode) -> Int
 var
-  return_code: Int := 0;
-  lexer: Tokenizer;
+  return_code: Int := 0
+  lexer: Tokenizer
 begin
   if command_line^.lex or command_line^.parse then
     lexer := lexer_text(source_code)
@@ -796,16 +795,16 @@ begin
   end;
 
   return return_code
-end;
+end
 
-proc process(argc: Int, argv: ^^Char) -> Int;
+proc process(argc: Int, argv: ^^Char) -> Int
 var
-  tokens: ^Token;
-  tokens_size: Word;
-  source_code: SourceCode;
-  command_line: ^CommandLine;
-  return_code: Int := 0;
-  source_file: ^SourceFile;
+  tokens: ^Token
+  tokens_size: Word
+  source_code: SourceCode
+  command_line: ^CommandLine
+  return_code: Int := 0
+  source_file: ^SourceFile
 begin
   command_line := parse_command_line(argc, argv);
   if command_line = nil then
@@ -835,7 +834,7 @@ begin
     return_code := compile_in_stages(command_line, source_code)
   end;
   return return_code
-end;
+end
 
   return process(count, parameters)
 end.