Hi, here are some build screw-ups one can create by switching off the wrong options: o CONFIG_XENO_OPT_NATIVE_REGISTRY (but CONFIG_XENO_OPT_PERVASIVE remains on): unresolved symbols rt_registry_bind and rt_registry_fetch, several warnings due to "#[el]if CONFIG_XENO_..." instead of "#[el]if defined(CONFIG_XENO_...)" o CONFIG_XENO_OPT_PERVASIVE: xnheap_init_mapped and xnheap_destroy_mapped become unresolved The first issue reminds me of my unanswered question if (CONFIG_XENO_OPT_PERVASIVE && CONFIG_XENO_SKIN_NATIVE && !CONFIG_XENO_OPT_NATIVE_REGISTRY) makes any sense at all (kernel objects created from user space are looked up via the registry, right?). I haven't worked out any patch for those issues. Actually, I only wanted to put this patch forward when stumbling over the other: --- ksrc/skins/native/Kconfig (revision 564) +++ ksrc/skins/native/Kconfig (working copy) @@ -127,7 +127,6 @@ config XENO_OPT_NATIVE_INTR bool "Interrupts" - default y help This option provides a simple API to deal with interrupts, Rationale: the /default/ way of handling IRQs should be via RTDM-based drivers. Only users who know what they are doing should leave this path and will have to switch on this feature explicitly. If this view can be commonly accepted, I will add some lines to the feature's help text as well. Jan