diff --git a/ast.c b/ast.c
index 8de6e85..51912e9 100644
--- a/ast.c
+++ b/ast.c
@@ -1361,6 +1361,10 @@ bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_valu
     for (i = 0; i < vec_size(self->exprs); ++i)
     {
         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
+        if (func->curblock->final) {
+            asterror(ast_ctx(self->exprs[i]), "unreachable statement");
+            return false;
+        }
         if (!(*gen)(self->exprs[i], func, false, out))
             return false;
     }