gcc/testsuite/gdc.test/compilable/issue21813a.d

// https://issues.dlang.org/show_bug.cgi?id=21813
Target.OS defaultTargetOS()
{
    return Target.OS.linux;
}

struct Target
{
    enum OS { linux }
    OS os = defaultTargetOS();
    void deinitialize() { this = this.init; }
    @property isPOSIX() scope @nogc { }
}