Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

PR12778.cpp
// RUN: %clang_cc1 -fsyntax-only -verify %s

void operator delete() throw(void*); // expected-error{{'operator delete' must have at least one parameter}}
void* allocate(int __n) {
   return ::operator new(__n);
}