Change LAMMPS_SIZE_LIMIT to LAMMPS_SIZES and use lower case values

  list(APPEND LAMMPS_LINK_LIBS mpi_stubs)

endif()

set(LAMMPS_SIZE_LIMIT "LAMMPS_SMALLBIG" CACHE STRING "Lammps size limit")

set_property(CACHE LAMMPS_SIZE_LIMIT PROPERTY STRINGS LAMMPS_SMALLBIG LAMMPS_BIGBIG LAMMPS_SMALLSMALL)

add_definitions(-D${LAMMPS_SIZE_LIMIT})

set(LAMMPS_API_DEFINES "${LAMMPS_API_DEFINES} -D${LAMMPS_SIZE_LIMIT}")

set(LAMMPS_SIZES "smallbig" CACHE STRING "LAMMPS size limit")

set_property(CACHE LAMMPS_SIZES PROPERTY STRINGS smallbig bigbig smallsmall)

string(TOUPPER ${LAMMPS_SIZES} LAMMPS_SIZES_DEFINE)

add_definitions(-DLAMMPS_${LAMMPS_SIZES_DEFINE})

set(LAMMPS_API_DEFINES "${LAMMPS_API_DEFINES} -DLAMMPS_${LAMMPS_SIZES_DEFINE}")

# posix_memalign is not available on Windows

if(NOT ${CMAKE_SYSTEM_NAME} STREQUAL "Windows")

  if(${FFTW}_FOUND)

    set(FFT "${FFTW}" CACHE STRING "FFT library for KSPACE package")

  else()

    set(FFT "KISSFFT" CACHE STRING "FFT library for KSPACE package")

    set(FFT "KISS" CACHE STRING "FFT library for KSPACE package")

  endif()

  set_property(CACHE FFT PROPERTY STRINGS KISSFFT ${FFTW} MKL)

  if(NOT FFT STREQUAL "KISSFFT")

  set_property(CACHE FFT PROPERTY STRINGS KISS ${FFTW} MKL)

  if(NOT FFT STREQUAL "KISS")

    find_package(${FFT} REQUIRED)

    if(NOT FFT STREQUAL "FFTW3F")

      add_definitions(-DFFT_FFTW)

    include_directories(${${FFT}_INCLUDE_DIRS})

    list(APPEND LAMMPS_LINK_LIBS ${${FFT}_LIBRARIES})

  else()

    add_definitions(-DFFT_KISSFFT)

    add_definitions(-DFFT_KISS)

  endif()

  set(PACK_OPTIMIZATION "PACK_ARRAY" CACHE STRING "Optimization for FFT")

  set_property(CACHE PACK_OPTIMIZATION PROPERTY STRINGS PACK_ARRAY PACK_POINTER PACK_MEMCPY)

  if(NOT PACK_OPTIMIZATION STREQUAL "PACK_ARRAY")

    add_definitions(-D${PACK_OPTIMIZATION})

  set(FFT_PACK "array" CACHE STRING "Optimization for FFT")

  set_property(CACHE PACK_OPTIMIZATION PROPERTY STRINGS array pointer memcpy)

  if(NOT FFT_PACK STREQUAL "array")

    string(TOUPPER ${FFT_PACK} FFT_PACK_DEFINE)

    add_definitions(-DFFT_PACK_${FFT_PACK_DEFINE})

  endif()

endif()