Yes, GCC 4.2.1 for tier 2 and 3 architectures only (like MIPS or PPC) for quite some time.
Clang/LLVM was imported into FreeBSD base in FreeBSD 9, released in 2012[1]. I don't believe it was the system compiler for any arch at that time, but could be wrong. In FreeBSD 10 (2014) it became the default compiler for amd64/i386[2].