I'm working on switching to LLVM's lld linker as the FreeBSD system linker (/usr/bin/ld), and the port in this PR is reported as a new failure in the exp-run, PR 214864.
An excerpt from the build log:
ld: error: unable to find library -lc
Known issues in this port or in lld that affect this port:
(2) lld has no built-in search paths (/lib, /usr/lib). Normally the linker is invoked from the compiler driver, and the search paths are added by the compiler. If lld is invoked directly library search paths must be specified explicitly, with -L/lib -L/usr/lib.
FreeBSD 11 and later have lld available as /usr/bin/ld.lld, so one simple option for testing is to just symlink /usr/bin/ld to ld.lld (and restore it to ld.bfd).
A port Makefile knob, LLD_UNSAFE=yes, exists to indicate that a port does not work with lld, and requires either /usr/bin/ld.bfd or binutils from ports. This should work for the common case of ports written in C using GNU autoconf; it may have no effect on other ports.
A commit references this bug:
Date: Tue Mar 27 21:11:25 UTC 2018
New revision: 465755
devel/pdcurses: use BINARY_ALIAS to ensure linker is ld.bfd
lld has no built-in search paths (/lib, /usr/lib). Normally the linker
is invoked from the compiler driver, and the search paths are added by
the compiler. If lld is invoked directly library search paths must be
specified explicitly, with -L/lib -L/usr/lib.
This port does not honour LD or -fuse-ld in CFLAGS via LLD_UNSAFE, but
BINARY_ALIAS can be used to ensure we use the BFD linker.
Approved by: portmgr (LLD_UNSAFE blanket)
Sponsored by: The FreeBSD Foundation