Compilation failure with Clang 17 and `-std=cpp23`

[planetmarshall]

Summary

Including <boost/program_options.hpp> causes a compilation failure when compiling with clang 17.0.6 and GNU stdlibc++ 14 with -std=gnu++23

Steps to reproduce

Install boost (a conanfile is provided) and extract the attached archive.

boost-po-test.tar.gz

tar -xf boost-po-test-tgz
cd boost-po-test/
cmake --preset default
cmake --build build/default

Expected result

compilation is successful

Actual result

compilation fails with

/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/14.1.1/../../../../include/c++/14.1.1/tuple:956:36: error: no matching function for call to 'get'
  956 |             return __convertible<decltype(std::get<_Is>(std::declval<_UTuple>()))...>();

Workaround

Edit the CMakeLists.txt file and change

set(CMAKE_CXX_STANDARD 23)

to

set(CMAKE_CXX_STANDARD 20)

and recompile.

System Info

Boost 1.85.0 (conan)
Arch Linux
Clang 17.0.6
GCC 14.1.1

[vprus]

Andrew, thanks for such a nice bug report.

Sadly, I'm far away from C++ these days, so our only hope for a fix is if somebody else, or maybe you, writes a PR.

Thanks again!

[planetmarshall]

No problem. Thanks for taking the time to look and your hard work on the library.