Prioritize errors from __main__ in multipass analysis

trans/transpiler/phases/typing/common.py

@@ -42,7 +42,7 @@ class ScoperVisitor(NodeVisitorSeq):
                         self.visit_function_definition(node, rtype)
                     except CompileError as e:
                         new_list.append((node, rtype))
-                        if not exc:
+                        if not exc or getattr(node, "is_main", False):
                             exc = e
                 if len(new_list) == len(old_list):
                     raise exc