Building examples with specified path of omega_h install

[joshia5]

following errors when building examples with scorec/omega_h, (https://github.com/SCOREC/omega_h ) after make command

build instructions

module load gcc mpich cmake
export kk= # This is where kokkos is installed
export oh= # This is where omega_h is installed
module load cuda/10.2
export LD_LIBRARY_PATH=$cuda/lib64:$LD_LIBRARY_PATH
export CMAKE_PREFIX_PATH=$engpar:$kk:$oh:$CMAKE_PREFIX_PATH
export MPICH_CXX=$root/kokkos/bin/nvcc_wrapper
git clone git@github.com:SCOREC/omegah_examples.git
mkdir build-ohExamples-cuda
cd !$
cmake ../omegah_examples -DCMAKE_CXX_COMPILER=mpicxx
make

error in make

g++: error: cross-execution-space-call,deprecated-declarations: No such file or directory
g++: error: unrecognized command line option '--compiler-options'; did you mean '--no-exceptions'?
g++: error: unrecognized command line option '-W,-Wall,-Wextra,-Werror,-Wno-noexcept-type'
g++: error: unrecognized command line option '--Werror'; did you mean '-Werror'?
g++: error: unrecognized command line option '--expt-extended-lambda'
make[2]: *** [CMakeFiles/hypercube.dir/hypercube.cpp.o] Error 1
make[1]: *** [CMakeFiles/hypercube.dir/all] Error 2
make: *** [all] Error 2

[cwsmith]

@joshia5 The hack that we used in mfem was to remove these flags by modifying the mfem CMakeLists.txt after the flags are brought in by find_package(omegah).

https://github.com/SCOREC/mfem/blob/c8dc12486d4117a00b729c9b14a7e8fc8cdc521d/CMakeLists.txt#L344-L359

In the short-term, we can either port the hack from mfem to omegah_examples, or try disabling the warning flags when you build omegah via cmake command line options; I think there is a 'disable_warnings' or cxx_warnings=off...

The long-term solution is to get a better understanding of how to deal with the flags. We should probably ask Dan about this to see how he writes cmake integration for his applications that use omegah.