lld uses argv to determine the operating mode, and expects ld.lld[suffix] to operate in GNU ld mode, for Clang's -fuse-ld= arg.
% sudo cp /usr/local/bin/lld-devel /usr/local/bin/ld.lld-devel
% cc -fuse-ld=lld-devel hello.c
A commit references this bug:
Date: Wed Dec 7 20:03:42 UTC 2016
New revision: 428083
Update to a fresh snapshot.
Sponsored by: DARPA, AFRL