if(NOT DEFINED ENV{FCFLAGS})
    if(CMAKE_Fortran_COMPILER_ID MATCHES XL)
        set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -qzerosize -qextname -qsuppress=cmpmsg")
        set(CMAKE_Fortran_FLAGS_RELEASE "-O3")
        set(CMAKE_Fortran_FLAGS_DEBUG "-g")
    endif()
endif()