Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

invalid-opaque-ptr-double-addrspace.ll
; RUN: not llvm-as < %s -opaque-pointers -disable-output 2>&1 | FileCheck %s

; CHECK: expected top-level entity
@g1 = external global ptr addrspace(3) addrspace(4)