Describe the bug
Ninja build with -Denable-autodiff=true or -Denable-directdiff=true failed.
Build success with both option = false

To Reproduce
set either -Denable-autodiff=true or -Denable-directdiff=true and rebuild

Desktop (please complete the following information):

• OS: Macosx BigSur
• C++ compiler and version: clang-1200.0.32.29
• MPI implementation and version: OpenMPI 4.0.5 [via homebrew]
• SU2 Version: 7.1.0 [via git]

Attached are the logs for ninja build and meson.py --reconfigure
Cheers
bakakouhai

ninja.log
meson.log