bump clang version to 13 or fails under clang 11

[kluete]

the error with clang11 was:

$ clang++-11 --version Debian clang version 11.0.1-2 Target: x86_64-pc-linux-gnu

$ clang++-11 -std=c++2a range.example.cpp In file included from range.example.cpp:11: In file included from ./tc/string/format.h:14: ./tc/string/../algorithm/empty.h:29:108: error: a non-type template parameter cannot have type 'std::integral_constant<tc::break_or_continue_adl::break_or_continue, tc::break_or_continue_adl::break_orcontinue::break>' return [&]() returnMAYTHROW(tc::continue==tc::for_each(tc_move_if_owned(rng), tc::constexprfunction<tc::constant<tc::break>{}>())); ^ ./tc/range/../algorithm/../base/trivial_functors.h:26:17: note: template parameter is declared here template ^ In file included from range.example.cpp:11: In file included from ./tc/string/format.h:14: ./tc/string/../algorithm/empty.h:29:108: error: a non-type template parameter cannot have type 'std::integral_constant<tc::break_or_continue_adl::break_or_continue, tc::break_or_continue_adl::break_orcontinue::break>' return [&]() returnMAYTHROW(tc::continue==tc::for_each(tc_move_if_owned(rng), tc::constexprfunction<tc::constant<tc::break>{}>())); ^ ./tc/range/../algorithm/../base/trivial_functors.h:26:17: note: template parameter is declared here template ^ 2 errors generated.

[stheophil]

Thanks. I will update the README. We also support gcc12 now.