Re: build failure affecting port: "error: reference to 'filesystem' is ambiguous"

On 30 Apr 2024, at 14:26, Nuno Teixeira <eduardo@freebsd.org> wrote:
> 
> I'm lost on build failure of audio/amsynth (updated to version 1.13.3) on recent main.
> Thre strange thing is if I use llvm from ports, USES+=llvm, it fails with same error so I suspect that something related to main.
> 
> Any help is welcome and I didn't openned an upstream PR yet.
> 
> Thanks,
> 
> ---
> src/Configuration.cpp:35:20: error: reference to 'filesystem' is ambiguous
>    35 |         amsynthrc_fname = filesystem::get().config;
>       |                           ^
> src/filesystem.h:27:7: note: candidate found by name lookup is 'filesystem'
>    27 | class filesystem
>       |       ^
> /usr/include/c++/v1/__chrono/file_clock.h:49:1: note: candidate found by name lookup is 'std::filesystem'
>    49 | _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
>       | ^
> /usr/include/c++/v1/__config:892:80: note: expanded from macro '_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM'
>   892 |                                              inline namespace __fs { namespace filesystem {
>       |                                                                                ^

It looks like the program defines its own "filesystem" class, and also
has "using namespace std;". 

Usually the easiest fix is to use "::filesystem" for the call sites that
want to use the program's own definition.

Alternatively, rename the 'local' definition to something else, like
"my_filesystem".

-Dimitry