builtin-constant.x

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

set torture_eval_before_execute {
    global compiler_conditional_xfail_data
    set compiler_conditional_xfail_data {
        "This test fails on all targets when optimizing." \
        { "*-*-*" } \
        { "*" } \
        { "-O0" }
    }
}

return 0