diff --git a/examples/gen_ok.rs b/examples/gen_ok.rs
new file mode 100644
index 0000000000..076bb81557
--- /dev/null
+++ b/examples/gen_ok.rs
@@ -0,0 +1,352 @@
+#![feature(prelude_import)]
+//! examples/idle.rs
+#![feature(generator_trait)]
+#![feature(generators)]
+#![feature(never_type)]
+#![feature(type_alias_impl_trait)]
+#![feature(const_fn)]
+#![feature(fmt_internals)]
+#![feature(compiler_builtins_lib)]
+#![no_main]
+#![no_std]
+#[rustfmt::skip]
+#[prelude_import]
+use core::prelude::v1::*;
+#[macro_use]
+extern crate core;
+#[macro_use]
+extern crate compiler_builtins;
+
+use core::ops::Generator;
+use cortex_m_semihosting::{debug, hprintln};
+use lm3s6965::Interrupt;
+use panic_semihosting as _;
+use rtfm::{Exclusive, Mutex};
+
+#[allow(non_snake_case)]
+fn init(_: init::Context) {
+    // #[task(binds = GPIOA, resources = [shared2])]
+    // // fn foo1(ctx: &'static mut foo1::Context) -> impl Generator<Yield = (), Return = !> {
+    // fn foo1(mut ctx: foo1::Context) -> impl Generator<Yield = (), Return = !> {
+    //     let mut local = 0;
+    //     //let shared_res = Exclusive(ctx.resources.shared);
+    //     // static shared_res : &mut u32 = ctx.resources.shared;
+    //     // hprintln!("init foo1: {}", ctx.resources.shared);
+    //     static mut X: u32 = 0;
+    //     // let mut e = Exclusive(unsafe { &mut X });
+    //     // //let mut e = Exclusive(ctx.resources.shared);
+    //     // hprintln!(
+    //     //     "ex {:?}",
+    //     //     e.lock(|v| {
+    //     //         *v += 1;
+    //     //         *v
+    //     //     })
+    //     // )
+    //     // .unwrap();
+    //     hprintln!("{}", ctx.resources.shared2.lock(|v| *v));
+    //     move || loop {
+    //         hprintln!("foo1_1 {} {}", local, unsafe { X }).unwrap();
+    //         // hprintln!(
+    //         //     "ex {}",
+    //         //     e.lock(|v| {
+    //         //         *v += 1;
+    //         //         *v
+    //         //     })
+    //         // )
+    //         // .unwrap();
+
+    //         local += 1;
+    //         // shared_res.lock(|s| hprintln!("s {}", s));
+    //         //   *shared_res += 1;
+    //         // *ctx.resources.shared += 1;
+    //         unsafe { X += 1 };
+    //         yield;
+    //         hprintln!("foo1_2 {} {}", local, unsafe { X }).unwrap();
+    //         local += 1;
+    //         // unsafe { X += 1 };
+    //         yield;
+    //     }
+    // }
+
+    // ctx.resources.shared2.lock(|v| *v);
+    //        hprintln!("{}", ctx.resources.shared2.lock(|v| *v)).unwrap();
+
+    ::cortex_m_semihosting::export::hstdout_str("init\n").unwrap();
+    rtfm::pend(Interrupt::GPIOA);
+}
+#[allow(non_snake_case)]
+fn idle(_: idle::Context) -> ! {
+    use rtfm::Mutex as _;
+    ::cortex_m_semihosting::export::hstdout_str("idle\n").unwrap();
+    rtfm::pend(Interrupt::GPIOA);
+    ::cortex_m_semihosting::export::hstdout_str("idle1\n").unwrap();
+    rtfm::pend(Interrupt::GPIOA);
+    debug::exit(debug::EXIT_SUCCESS);
+    loop {}
+}
+#[rustfmt::skip]
+type Generatorfoo1= impl Generator<Yield = (), Return = !>;
+static mut GENERATOR_FOO1: core::mem::MaybeUninit<Generatorfoo1> =
+    core::mem::MaybeUninit::uninit();
+#[allow(non_snake_case)]
+fn foo1(mut ctx: foo1::Context) -> Generatorfoo1 {
+    use rtfm::Mutex as _;
+    //    ctx.resources.shared2.lock(|v| *v);
+    move || loop {
+        ctx.resources.shared2.lock(|v| {
+            *v += 1;
+            hprintln!("{}", v)
+        });
+        ::cortex_m_semihosting::export::hstdout_str("foo1_1\n").unwrap();
+        yield;
+        ctx.resources.shared2.lock(|v| {
+            *v += 1;
+            hprintln!("{}", v)
+        });
+        ::cortex_m_semihosting::export::hstdout_str("foo1_2\n").unwrap();
+        yield;
+    }
+}
+#[allow(non_snake_case)]
+fn foo2(mut ctx: foo2::Context) {
+    use rtfm::Mutex as _;
+    ctx.resources.shared2.lock(|v| *v += 1);
+}
+#[allow(non_snake_case)]
+fn foo3(mut ctx: foo3::Context) {
+    use rtfm::Mutex as _;
+    ctx.resources.shared2.lock(|v| *v += 1);
+}
+#[allow(non_snake_case)]
+#[doc = "Initialization function"]
+pub mod init {
+    fn plepps() {}
+    #[doc = r" Execution context"]
+    pub struct Context {
+        #[doc = r" Core (Cortex-M) peripherals"]
+        pub core: rtfm::export::Peripherals,
+    }
+    impl Context {
+        #[inline(always)]
+        pub unsafe fn new(core: rtfm::export::Peripherals) -> Self {
+            Context { core }
+        }
+    }
+}
+#[allow(non_snake_case)]
+#[doc = "Idle loop"]
+pub mod idle {
+    fn plepps() {}
+    #[doc = r" Execution context"]
+    pub struct Context {}
+    impl Context {
+        #[inline(always)]
+        pub unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            Context {}
+        }
+    }
+}
+mod resources {
+    use rtfm::export::Priority;
+    #[allow(non_camel_case_types)]
+    pub struct shared2 {
+        priority: Priority,
+    }
+    impl shared2 {
+        #[inline(always)]
+        pub unsafe fn new(priority: Priority) -> Self {
+            shared2 { priority }
+        }
+        #[inline(always)]
+        pub unsafe fn priority(&self) -> Priority {
+            self.priority.clone()
+        }
+    }
+}
+#[allow(non_snake_case)]
+#[doc = "Resources `foo1` has access to"]
+pub struct foo1Resources {
+    pub shared2: resources::shared2,
+}
+#[allow(non_snake_case)]
+#[doc = "Hardware task"]
+pub mod foo1 {
+    fn plepps() {}
+    #[doc(inline)]
+    pub use super::foo1Resources as Resources;
+    #[doc = r" Execution context"]
+    pub struct Context {
+        #[doc = r" Resources this task has access to"]
+        pub resources: Resources,
+    }
+    impl<'a> Context {
+        #[inline(always)]
+        pub unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            Context {
+                resources: Resources::new(priority),
+            }
+        }
+    }
+}
+#[allow(non_snake_case)]
+#[doc = "Resources `foo2` has access to"]
+pub struct foo2Resources {
+    pub shared2: resources::shared2,
+}
+#[allow(non_snake_case)]
+#[doc = "Hardware task"]
+pub mod foo2 {
+    fn plepps() {}
+    #[doc(inline)]
+    pub use super::foo2Resources as Resources;
+    #[doc = r" Execution context"]
+    pub struct Context {
+        #[doc = r" Resources this task has access to"]
+        pub resources: Resources,
+    }
+    impl Context {
+        #[inline(always)]
+        pub unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            Context {
+                resources: Resources::new(priority),
+            }
+        }
+    }
+}
+#[allow(non_snake_case)]
+#[doc = "Resources `foo3` has access to"]
+pub struct foo3Resources {
+    pub shared2: resources::shared2,
+}
+#[allow(non_snake_case)]
+#[doc = "Hardware task"]
+pub mod foo3 {
+    fn plepps() {}
+    #[doc(inline)]
+    pub use super::foo3Resources as Resources;
+    #[doc = r" Execution context"]
+    pub struct Context {
+        #[doc = r" Resources this task has access to"]
+        pub resources: Resources,
+    }
+    impl Context {
+        #[inline(always)]
+        pub unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            Context {
+                resources: Resources::new(priority),
+            }
+        }
+    }
+}
+#[doc = r" Implementation details"]
+const APP: () = {
+    #[doc = r" Always include the device crate which contains the vector table"]
+    use lm3s6965 as _;
+    #[allow(non_upper_case_globals)]
+    static mut shared2: u32 = 1;
+    impl<'a> rtfm::Mutex for resources::shared2 {
+        type T = u32;
+        #[inline(always)]
+        fn lock<R>(&mut self, f: impl FnOnce(&mut u32) -> R) -> R {
+            #[doc = r" Priority ceiling"]
+            const CEILING: u8 = 3u8;
+            unsafe {
+                rtfm::export::lock(
+                    &mut shared2,
+                    &self.priority(),
+                    CEILING,
+                    lm3s6965::NVIC_PRIO_BITS,
+                    f,
+                )
+            }
+        }
+    }
+    #[allow(non_snake_case)]
+    #[no_mangle]
+    unsafe fn GPIOA() {
+        const PRIORITY: u8 = 1u8;
+        rtfm::export::run(PRIORITY, || {
+            ::cortex_m_semihosting::export::hstdout_str("interrupt dispatch\n")
+                .unwrap();
+            let mut g: &mut dyn Generator<Yield = (), Return = !> =
+                &mut *GENERATOR_FOO1.as_mut_ptr();
+            core::pin::Pin::new_unchecked(&mut *g).resume();
+        });
+    }
+    impl foo1Resources {
+        #[inline(always)]
+        unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            foo1Resources {
+                shared2: resources::shared2::new(priority),
+            }
+        }
+    }
+    #[allow(non_snake_case)]
+    #[no_mangle]
+    unsafe fn GPIOB() {
+        const PRIORITY: u8 = 2u8;
+        rtfm::export::run(PRIORITY, || {
+            crate::foo2(foo2::Context::new(rtfm::export::Priority::new(
+                PRIORITY,
+            )))
+        });
+    }
+    impl<'a> foo2Resources {
+        #[inline(always)]
+        unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            foo2Resources {
+                shared2: resources::shared2::new(priority),
+            }
+        }
+    }
+    #[allow(non_snake_case)]
+    #[no_mangle]
+    unsafe fn GPIOC() {
+        const PRIORITY: u8 = 3u8;
+        rtfm::export::run(PRIORITY, || {
+            crate::foo3(foo3::Context::new(rtfm::export::Priority::new(
+                PRIORITY,
+            )))
+        });
+    }
+    impl foo3Resources {
+        #[inline(always)]
+        unsafe fn new(priority: rtfm::export::Priority) -> Self {
+            foo3Resources {
+                shared2: resources::shared2::new(priority),
+            }
+        }
+    }
+    #[no_mangle]
+    unsafe extern "C" fn main() -> ! {
+        rtfm::export::interrupt::disable();
+        let mut core: rtfm::export::Peripherals = core::mem::transmute(());
+        let _ = [(); ((1 << lm3s6965::NVIC_PRIO_BITS) - 1u8 as usize)];
+        core.NVIC.set_priority(
+            lm3s6965::Interrupt::GPIOA,
+            rtfm::export::logical2hw(1u8, lm3s6965::NVIC_PRIO_BITS),
+        );
+        rtfm::export::NVIC::unmask(lm3s6965::Interrupt::GPIOA);
+        let _ = [(); ((1 << lm3s6965::NVIC_PRIO_BITS) - 2u8 as usize)];
+        core.NVIC.set_priority(
+            lm3s6965::Interrupt::GPIOB,
+            rtfm::export::logical2hw(2u8, lm3s6965::NVIC_PRIO_BITS),
+        );
+        rtfm::export::NVIC::unmask(lm3s6965::Interrupt::GPIOB);
+        let _ = [(); ((1 << lm3s6965::NVIC_PRIO_BITS) - 3u8 as usize)];
+        core.NVIC.set_priority(
+            lm3s6965::Interrupt::GPIOC,
+            rtfm::export::logical2hw(3u8, lm3s6965::NVIC_PRIO_BITS),
+        );
+        rtfm::export::NVIC::unmask(lm3s6965::Interrupt::GPIOC);
+        let late = init(init::Context::new(core.into()));
+        const PRIORITY: u8 = 1u8;
+        unsafe {
+            GENERATOR_FOO1.as_mut_ptr().write(foo1(foo1::Context::new(
+                rtfm::export::Priority::new(PRIORITY),
+            )));
+        };
+        rtfm::export::interrupt::enable();
+        idle(idle::Context::new(rtfm::export::Priority::new(0)))
+    }
+};