Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

PR49534.cpp
// RUN: %clang_cc1 -x c++ -fsyntax-only %s -verify

static union {     // expected-warning {{declaration does not declare anything}}
  virtual int a(); // expected-error {{unions cannot have virtual functions}}
};