Fails to build with libc++ 19

[jbeich]

Regressed by llvm/llvm-project@c3668779c135. From error log:

$ export CC=clang CXX=clang++ CXXFLAGS=-stdlib=libc++
$ cmake -G Ninja -B _build
$ cmake --build _build
[...]
/usr/include/c++/v1/string:820:42: error: implicit instantiation of undefined template 'std::char_traits<unsigned long>'
  static_assert(is_same<_CharT, typename traits_type::char_type>::value,
                                         ^
rpcs3/Emu/Cell/PPUAnalyser.h:184:25: note: in instantiation of template class 'std::basic_string<unsigned int>' requested here
        std::basic_string<u32> applied_patches;
                               ^
rpcs3/Emu/Cell/lv2/sys_prx.h:198:26: note: in instantiation of template class 'std::basic_string<bool>' requested here
        std::basic_string<bool> m_loaded_flags;
                                ^
rpcs3/Emu/System.cpp:1228:39: note: in instantiation of template class 'std::basic_string_view<unsigned char>' requested here
                                        const std::basic_string_view<u8> dirname{reinterpret_cast<const u8*>(game_data.data()), game_data.size()};
                                                                         ^
rpcs3/util/logs.cpp:401:52: note: in instantiation of template class 'std::basic_string<unsigned long>' requested here
        /*constinit thread_local*/ std::basic_string<u64> args;
                                                          ^
rpcs3/util/logs.cpp:410:7: note: in instantiation of member function 'std::basic_string<unsigned long>::resize' requested here
        args.resize(args_count);
             ^
Utilities/bin_patch.cpp:912:38: note: in instantiation of template class 'std::basic_string<unsigned int>' requested here
        const usz old_applied_size = applied.size();
                                            ^
Utilities/bin_patch.cpp:992:14: note: in instantiation of member function 'std::basic_string<unsigned int>::push_back' requested here
                                        applied.push_back(::narrow<u32>(&p - patch.data_list.data())); // Remember index in case of failure to allocate any memory
                                                ^
Utilities/bin_patch.cpp:1012:11: note: in instantiation of member function 'std::basic_string<unsigned int>::resize' requested here
                applied.resize(old_applied_size);
                        ^
/usr/include/c++/v1/string_view:300:42: error: implicit instantiation of undefined template 'std::char_traits<unsigned char>'
  static_assert(is_same<_CharT, typename traits_type::char_type>::value,
                                         ^
Utilities/File.cpp:296:31: note: in instantiation of template class 'std::basic_string_view<unsigned char>' requested here
                        std::basic_string_view<u8> data_view;
                                                   ^
Utilities/File.cpp:332:61: note: in instantiation of function template specialization 'std::__1::operator==<unsigned char, std::char_traits<unsigned char>>' requested here
                return _rhs.type_view == _lhs.type_view && _rhs.data_view == _lhs.data_view;
                                                                          ^
rpcs3/Crypto/unedat.cpp:617:15: note: in instantiation of template class 'std::basic_string_view<unsigned char>' requested here
        for (usz i = std::basic_string_view<u8>(buf.get() + 0x30, file_name.size()).find_last_of('.'); i < buf_len; i++)
                     ^
rpcs3/Crypto/unedat.cpp:617:78: note: in instantiation of member function 'std::basic_string_view<unsigned char>::find_last_of' requested here
        for (usz i = std::basic_string_view<u8>(buf.get() + 0x30, file_name.size()).find_last_of('.'); i < buf_len; i++)
                                                                                    ^
rpcs3/Emu/Cell/PPUAnalyser.h:180:8: note: while declaring the implicit move constructor for 'main_ppu_module'
struct main_ppu_module : public ppu_module
       ^
rpcs3/Emu/Cell/PPUAnalyser.h:184:25: note: in instantiation of template class 'std::basic_string<unsigned int>' requested here
        std::basic_string<u32> applied_patches;
                               ^
rpcs3/Loader/PSF.cpp:78:45: note: in instantiation of template class 'std::basic_string_view<unsigned char>' requested here
                fmt::append(out, "%s: %s\n", entry.first, std::basic_string_view<u8>(reinterpret_cast<const u8*>(entry.second.as_string().data()), entry.second.size()));
                                                          ^

Affects future versions of FreeBSD, macOS and Chimera Linux. See also related downstream bug.

[oltolm]

I fixed it in a branch in my fork. I can submit a PR later.

[Nekotekina]

It's a bit complicated... It should be some sort of FixedVector in some cases, or probably just vector in another.