The builds used to complete normally by default. `CFLAGS="-O2" pyenv install 3.6.7` resolves the issue. ### Description - [X] Platform information (e.g. Ubuntu Linux 16.04): Fedora 34 - [X] OS architecture (e.g. amd64): amd64 - [X] pyenv version: 2.0.6 - [X] Python version: [3.6.7; 3.7.3] - [X] C Compiler information (e.g. gcc 7.3): gcc 11.2.1 - [X] Please attach verbose build log as gist * You can turn on verbose debug logging using by setting `PYENV_DEBUG=1`, e.g. `env PYENV_DEBUG=1 pyenv install -v 3.6.4`