compiler.blacklist does not work correctly now and prohibits new Clangs on 10.6 Intel

[barracuda156]

I cannot make the base to pick correct compilers now via blacklist for folly. What I need is clang-15 or later and not clang-11.

The port currently has:

compiler.cxx_standard   2017
compiler.blacklist-append {clang < 1100}
compiler.blacklist-append {macports-clang-[5-9].0}
compiler.blacklist-append macports-gcc-12

On 10.6.8 I get in result:

10:MacPorts-2.9.0 svacchanda$ port deps folly
Full Name: folly @2024.01.22.00_0
Build Dependencies:   cmake, ninja, clang-11, pkgconfig
Library Dependencies: bzip2, double-conversion, gflags, google-glog, libevent,
                      libsodium, libunwind, lz4, lzma, snappy, xz, zlib, zstd,
                      libfmt10, libcxx, boost181, openssl3, legacy-support,
                      macports-libcxx

I though C++17 will pick a newer clang, but anyway, clang-11 cannot built it, so I try adding:

compiler.blacklist-append {macports-clang-[5-9].0} macports-clang-10 macports-clang-11

And nothing, it still wants clang-11:

10:MacPorts-2.9.0 svacchanda$ port deps folly
Warning: All compilers are either blacklisted or unavailable; defaulting to first fallback option
Full Name: folly @2024.01.22.00_0
Build Dependencies:   cmake, ninja, clang-11, pkgconfig
Library Dependencies: bzip2, double-conversion, gflags, google-glog, libevent,
                      libsodium, libunwind, lz4, lzma, snappy, xz, zlib, zstd,
                      libfmt10, libcxx, boost181, openssl3, legacy-support,
                      macports-libcxx

Only compiler.whitelist macports-clang-16 works:

10:MacPorts-2.9.0 svacchanda$ port deps folly
Full Name: folly @2024.01.22.00_0
Build Dependencies:   cmake, ninja, clang-16, pkgconfig
Library Dependencies: bzip2, double-conversion, gflags, google-glog, libevent,
                      libsodium, libunwind, lz4, lzma, snappy, xz, zlib, zstd,
                      libfmt10, libcxx, boost181, openssl3, legacy-support,
                      macports-libcxx

There is no overriding compiler.blacklist in the portfile, everything is appended.