cmake HAVE_LIBFFTW examples

QMCPACK/qmcpack CMakeLists.txt :550 

target_compile_definitions(Math::FFTW3 INTERFACE "HAVE_LIBFFTW")

QMCPACK/qmcpack src/QMCHamiltonians/CMakeLists.txt :81 

endif(HAVE_LIBFFTW)