How to use a different C++ compiler?

[matthiashaedrich]

I am trying to package an extension module. My CMakeLists.txt file gets correctly used and builds the project.

However, compilation fails because of using static constexpr.

Now I noticed when poetry is creating its virtual environment it uses GNU 11.4 for compilation. So I checked which compilers are installed on the build server, and it is Clang 18 and GNU 13.3 For using static constexpr we have to use GNU 13.3.

How can I tell poetry or the virtual environment to use GNU 13.3 (or just the system's default C++ compiler) instead of GNU 11.4? And how would I tell it to use clang?

Output when creating the docker image the build will run in:

[3/3] RUN clang++ --version && g++ --version
0.122 Ubuntu clang version 18.1.3 (1ubuntu1)
0.122 Target: x86_64-pc-linux-gnu
0.122 Thread model: posix
0.122 InstalledDir: /usr/bin
0.125 g++ (Ubuntu 13.3.0-6ubuntu2~24.04) 13.3.0
0.125 Copyright (C) 2023 Free Software Foundation, Inc.

Output of poetry build:

running build_ext
-- The CXX compiler identification is GNU 11.4.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- The C compiler identification is GNU 11.4.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE

The installed Poetry version is 1.8.2.