Not a bug, but big annoyance: Sometime in the past 3 months, boost-libs have started depending on llvm60. Is this dep *really* needed? Due to this, my total compile time has drastically increased. :-/ llvm60 itself takes a loooong time to compile, plus the time for all its deps. Multiply this time by three (I'm using poudirere for building packages for three different FreeBSD versions) and half a day has passed before the builder has finished. :-) If the dep can be removed, please make efforts to do so.
Fix Summary and assign. However, I doubt that this will happen. The ports default compiler for 11.x and 12.x is llvm60.
Upgrade to FreeBSD 11.2 or 12.0 if you don't want llvm60. In-base Clang/libc++ 3.4 on FreeBSD 10.4 doesn't support C++14 but building with -std=c++14 (or -std=gnu++14) is required in order for Boost to be usable in C++14 consumers e.g., databases/clickhouse databases/mongodb34 databases/mongodb36 editors/jucipp math/cadabra2 multimedia/mkvtoolnix science/libgeodecomp sysutils/osquery www/osrm-backend https://github.com/boostorg/system/issues/24 If you really want to stick to FreeBSD 10.4 beware that I'm planning to drop support after EOL on 2018-10-31.
Once FreeBSD 10.4 and 11.1 support is gone ports/ can enjoy C++17 everywhere except some architectures stuck on GCC: sparc64, powerpc*, mips*, riscv*. Very few ports will depend on devel/llvm60 (or newer) e.g., graphics/mesa-dri needs libLLVM for Gallium, www/firefox needs libclang to generate Rust bindings for C/C++.