Silence buildbot errors for unsupported Mac OS versions?

[Leo Singer]

Hi,

I have a port, ds9, that supports only certain Mac OS variants (Lion or newer). This is currently enforced as :

platform darwin {
    if {${os.major} <= 10} {
        depends_lib
        depends_run
        ui_error "$name requires Mac OS X Lion or later."
        error "unsupported platform"
    }
}

But this causes buildbot failures for the unsupported Mac OS versions. How do I suppress the buildbot failures?

Thanks,
Leo