Support 0 prio tasks

examples/zero-prio-task.rs

@@ -0,0 +1,56 @@
+#![no_main]
+#![no_std]
+#![feature(type_alias_impl_trait)]
+
+use core::marker::PhantomData;
+use panic_semihosting as _;
+
+pub struct NotSend {
+    _0: PhantomData<*const ()>,
+}
+
+#[rtic::app(device = lm3s6965, peripherals = true)]
+mod app {
+    use super::NotSend;
+    use core::marker::PhantomData;
+    use cortex_m_semihosting::{debug, hprintln};
+
+    #[shared]
+    struct Shared {
+        x: NotSend,
+    }
+
+    #[local]
+    struct Local {
+        y: NotSend,
+    }
+
+    #[init]
+    fn init(_cx: init::Context) -> (Shared, Local) {
+        hprintln!("init");
+
+        async_task::spawn().unwrap();
+        async_task2::spawn().unwrap();
+
+        (
+            Shared {
+                x: NotSend { _0: PhantomData },
+            },
+            Local {
+                y: NotSend { _0: PhantomData },
+            },
+        )
+    }
+
+    #[task(priority = 0, shared = [x], local = [y])]
+    async fn async_task(_: async_task::Context) {
+        hprintln!("hello from async");
+    }
+
+    #[task(priority = 0, shared = [x])]
+    async fn async_task2(_: async_task2::Context) {
+        hprintln!("hello from async2");
+
+        debug::exit(debug::EXIT_SUCCESS); // Exit QEMU simulator
+    }
+}