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# - Define macro to check if linking to zlib actually works,
# because the find_package macro is content if one exists.  This can
# fail in cross-compilation environments, and we want to know about
# zlib so the zlib TNG support is built only when it will work.
#
#  GMX_TEST_ZLIB(VARIABLE)
#
#  VARIABLE will be set to true if zlib support is present

include(CheckLibraryExists)
include(gmxOptionUtilities)
function(GMX_TEST_ZLIB VARIABLE)
    if(ZLIB_FOUND)
        gmx_check_if_changed(_do_zlib_recompile ZLIB_INCLUDE_DIR ZLIB_LIBRARIES)
        if(_do_zlib_recompile)
            unset(ZLIB_LINKS_OK CACHE)
        endif()
        check_library_exists("${ZLIB_LIBRARIES}" "zlibVersion" "" ZLIB_LINKS_OK)
        set(${VARIABLE} ${ZLIB_LINKS_OK} PARENT_SCOPE)
    else()
        set(${VARIABLE} OFF PARENT_SCOPE)
    endif()
endfunction()