diff --git a/src/typechecker.cpp b/src/typechecker.cpp
index 7262438..84ad77a 100644
--- a/src/typechecker.cpp
+++ b/src/typechecker.cpp
@@ -27,11 +27,19 @@ namespace AST {
     }
 
     std::shared_ptr<types::Type> ValueReferenceExpression::typecheck(
-        typecheck::State&,
+        typecheck::State& state,
         typecheck::Scope& scope,
         std::optional<std::shared_ptr<types::Type>>
     ) {
-        return scope.symbols[this->m_name];
+        if (scope.symbols.contains(this->m_name)) {
+            return scope.symbols[this->m_name];
+        }
+        else {
+            state.errors.push_back(CompileError("Value " + this->m_name + " not defined", this->m_meta));
+            return std::shared_ptr<types::Type>{
+                new types::FundamentalType{ types::FundamentalTypeKind::Void }
+            };
+        }
     }
 
     std::shared_ptr<types::Type> BinaryOperationExpression::typecheck(
@@ -78,6 +86,7 @@ namespace AST {
 
     void ReturnStatement::typecheck(typecheck::State& state, typecheck::Scope& scope) {
         this->m_expr->typecheck(state, scope, scope.return_ty);
+        // TODO make sure returned type matches function return type.
     }
 
     void InitializationStatement::typecheck(typecheck::State& state, typecheck::Scope& scope) {
@@ -112,6 +121,7 @@ namespace AST {
         scope.symbols[this->m_name] = std::shared_ptr<types::Type>{ function_ty };
 
         typecheck::Scope inner{ scope };
+        inner.return_ty = return_ty;
 
         if (this->m_statements) {
             for (auto& statement : *this->m_statements) {