Create a new channel as a copy of main.
Rename main to:
Delete main? This cannot be undone.
// RUN: %clang -mbackchain --target=s390x-linux -S -emit-llvm -o - %s | FileCheck %s // CHECK: define dso_local void @foo() [[NUW:#[0-9]+]] void foo(void) { } // CHECK: attributes [[NUW]] = { {{.*}} "backchain" {{.*}} }