2 files changed, 41 insertions, 2 deletions
diff --git a/examples/schedule.rs b/examples/schedule.rs
index 97818e3..d5de9db 100644
--- a/examples/schedule.rs
+++ b/examples/schedule.rs
@@ -1,9 +1,11 @@
 //! examples/schedule.rs
 
+#![deny(unsafe_code)]
 #![deny(warnings)]
 #![no_main]
 #![no_std]
 
+use cortex_m::peripheral::DWT;
 use cortex_m_semihosting::hprintln;
 use panic_halt as _;
 use rtfm::cyccnt::{Instant, U32Ext as _};
@@ -15,11 +17,12 @@ const APP: () = {
     fn init(mut cx: init::Context) {
         // Initialize (enable) the monotonic timer (CYCCNT)
         cx.core.DCB.enable_trace();
-        // required on devices that software lock the DWT (e.g. STM32F7)
-        unsafe { cx.core.DWT.lar.write(0xC5ACCE55) }
+        // required on Cortex-M7 devices that software lock the DWT (e.g. STM32F7)
+        DWT::unlock();
         cx.core.DWT.enable_cycle_counter();
 
         // semantically, the monotonic timer is frozen at time "zero" during `init`
+        // NOTE do *not* call `Instant::now` in this context; it will return a nonsense value
         let now = cx.start; // the start time of the system
 
         hprintln!("init @ {:?}", now).unwrap();
diff --git a/examples/t-cfg-resources.rs b/examples/t-cfg-resources.rs
new file mode 100644
index 0000000..a8efe79
--- /dev/null
+++ b/examples/t-cfg-resources.rs
@@ -0,0 +1,36 @@
+//! [compile-pass] check that `#[cfg]` attributes applied on resources work
+//!
+#![no_main]
+#![no_std]
+
+use panic_halt as _;
+
+#[rtfm::app(device = lm3s6965)]
+const APP: () = {
+    struct Resources {
+        // A resource
+        #[init(0)]
+        shared: u32,
+
+        // A conditionally compiled resource behind feature_x
+        #[cfg(feature = "feature_x")]
+        x: u32,
+
+        dummy: (),
+    }
+
+    #[init]
+    fn init(_: init::Context) -> init::LateResources {
+        init::LateResources {
+            // The feature needs to be applied everywhere x is defined or used
+            #[cfg(feature = "feature_x")]
+            x: 0,
+            dummy: (), // dummy such that we have at least one late resource
+        }
+    }
+
+    #[idle]
+    fn idle(_cx: idle::Context) -> ! {
+        loop {}
+    }
+};