Problem building pio_lustre_perf reproducer

[roryck]

README suggests that 'make all' within the bugreports/derecho/pio_lustre_perf/ directory should be sufficient to build the reproducer, however, I get:
`---------------------------------------------
CMake 3.24.3, Copyright 2000-2022 Kitware, Inc. and Contributors

Error when bootstrapping CMake:
Cannot find appropriate C compiler on this system.
Please specify one using environment variable CC.
See cmake_bootstrap.log for compilers attempted.`

Do I need additional setup prior to 'make all' ?

[roryck]

Looks like I needed to

unset CC
unset FC
unset F77
unset LDFLAGS
unset FFLAGS
unset CFLAGS

prior to 'make all'

[benkirk]

Hmm, what's your working directory?

I would have expected the first two lines of build_cmake.sh to get you in a consistent state, then CXX and CC are specified on line 25, so not sure what's up.

(Runs successfully as csgteam in a new checkout)

[benkirk]

I'm guessing those are set in your user env in a way that don't disappear with the logic in config_env.sh ?
If so, I can harmlessly add the unsets to that script.

[roryck]

Yes, I had previously set those variables to build another tool and forgotten about it. Adding the unsets would solve the problem, but also probably an edge case if people are building from a fresh shell.