I upgraded from High Sierra to Big Sur, this meant that I hit some XCode changes.
These were solved via the following two commands:
xcode-select --install sudo xcode-select -switch /Library/Developer/CommandLineTools
xcode-select -switch isn’t necessary when upgrading from Catalina)
Then I went to my existing install of the GitHub CmdStan repo, which had existing CmdStan binaries and header files and tried to compile a model.
This failed because the PCH header file was out of date, so I did:
make clean-all; make -j4 build
Then I fired up Python and tried to do the same via CmdStanPy - all good!
As CmdStanPy doesn’t yet have a “rebuild CmdStan” utility, options are to
rebuild existing CmdStan install from the command line, per above commands,
or to run the
install_cmdstan function with argument