Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

objc-cpp-output.m
// RUN: %clang -emit-llvm -x objc-cpp-output -S %s -o /dev/null

// PR13820
// REQUIRES: LP64

// Should compile without errors
@protocol P
- (void)m;
@end
void f() {}