diff --git a/tests/cfail/borrow.rs b/tests/cfail/borrow.rs
index 14762dc7dc..6f9e1a863a 100644
--- a/tests/cfail/borrow.rs
+++ b/tests/cfail/borrow.rs
@@ -12,22 +12,26 @@ static R6: Resource<i32, C2> = Resource::new(0);
 fn j1(prio: P2) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R1, |ceil| {
-        // CAN borrow a resource with ceiling C when the current ceiling SC > C
-        let r2 = R2.borrow(&prio, ceil);
+    ceil.raise(
+        &R1, |ceil| {
+            // NOTE CC = Current Ceiling, P = task Priority
 
-        // CAN borrow a resource with ceiling C when the current ceiling SC == C
-        let r3 = R3.borrow(&prio, ceil);
+            // CAN borrow a resource with ceiling RC when CC > RC
+            let r2 = R2.borrow(&prio, ceil);
 
-        // CAN'T borrow a resource with ceiling C when the current ceiling SC < C
-        let r4 = R4.borrow(&prio, ceil);
-        //~^ error
+            // CAN borrow a resource with ceiling RC when CC == RC
+            let r3 = R3.borrow(&prio, ceil);
 
-        // CAN'T borrow a resource with ceiling C < P (task priority)
-        let r5 = R5.borrow(&prio, ceil);
-        //~^ error
+            // CAN'T borrow a resource with ceiling RC when CC < RC
+            let r4 = R4.borrow(&prio, ceil);
+            //~^ error
 
-        // CAN borrow a resource with ceiling C == P (task priority)
-        let r6 = R6.borrow(&prio, ceil);
-    });
+            // CAN'T borrow a resource with ceiling RC when RC < P
+            let r5 = R5.borrow(&prio, ceil);
+            //~^ error
+
+            // CAN borrow a resource with ceiling RC when RC == P
+            let r6 = R6.borrow(&prio, ceil);
+        }
+    );
 }
diff --git a/tests/cfail/ceiling.rs b/tests/cfail/ceiling.rs
index 8bbd1f7b40..b13be80239 100644
--- a/tests/cfail/ceiling.rs
+++ b/tests/cfail/ceiling.rs
@@ -7,20 +7,24 @@ static R1: Resource<(), C3> = Resource::new(());
 fn j1(prio: P2) {
     let ceil = prio.as_ceiling();
 
-    let c3 = ceil.raise(&R1, |ceil| {
-        // forbidden: ceiling token can't outlive critical section
-        ceil  //~ error
-    });
+    let c3 = ceil.raise(
+        &R1, |ceil| {
+            // forbidden: ceiling token can't outlive the critical section
+            ceil //~ error
+        }
+    );
 
     // Would be bad: lockless access to a resource with ceiling = 3
     let r2 = R1.borrow(&prio, c3);
 }
 
 fn j2(prio: P0) {
-    let c16 = rtfm::critical(|c16| {
-        // forbidden: ceiling token can't outlive critical section
-        c16  //~ error
-    });
+    let c16 = rtfm::critical(
+        |c16| {
+            // forbidden: ceiling token can't outlive the critical section
+            c16 //~ error
+        },
+    );
 
     // Would be bad: lockless access to a resource with ceiling = 16
     let r1 = R1.borrow(&prio, c16);
diff --git a/tests/cfail/lock.rs b/tests/cfail/lock.rs
index 36541f2542..ca4ea73c4d 100644
--- a/tests/cfail/lock.rs
+++ b/tests/cfail/lock.rs
@@ -4,17 +4,16 @@ use rtfm::{C16, C2, P1, P16, P2, P3, Resource};
 
 static R1: Resource<i32, C2> = Resource::new(0);
 
-// You CAN'T lock a resource with ceiling C from a task with priority P if P > C
+// You CAN'T use `raise` to lower the system ceiling
 fn j1(prio: P3) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R1, |ceil| {
-        //~^ error
-    });
+    ceil.raise(&R1, |ceil| {});
+    //~^ error
 }
 
-// DON'T lock a resource with ceiling equal to the task priority.
-// Instead use `borrow`
+// You don't need to raise the ceiling to access a resource with ceiling equal
+// to the task priority.
 fn j2(prio: P2) {
     let ceil = prio.as_ceiling();
 
@@ -25,28 +24,26 @@ fn j2(prio: P2) {
     let r1 = R1.borrow(&prio, ceil);
 }
 
-// You CAN lock a resource with ceiling C from a task with priority P if C > P
+// You CAN access a resource with ceiling C from a task with priority P if C > P
+// and you raise the ceiling first
 fn j3(prio: P1) {
     let ceil = prio.as_ceiling();
 
     // OK
-    ceil.raise(&R1, |ceil| {
-        let r1 = R1.borrow(&prio, ceil);
-    })
+    ceil.raise(&R1, |ceil| { let r1 = R1.borrow(&prio, ceil); })
 }
 
 static R2: Resource<i32, C16> = Resource::new(0);
 
-// Tasks with priority less than P16 can't lock a resource with ceiling C16
+// Tasks with priority less than P16 can't access a resource with ceiling C16
 fn j4(prio: P1) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R2, |ceil| {
-        //~^ error
-    });
+    ceil.raise(&R2, |ceil| {});
+    //~^ error
 }
 
-// Only tasks with priority P16 can claim a resource with ceiling C16
+// Only tasks with priority P16 can access a resource with ceiling C16
 fn j5(prio: P16) {
     // OK
     let r2 = R2.borrow(&prio, prio.as_ceiling());
diff --git a/tests/cfail/race-1.rs b/tests/cfail/race-1.rs
index e9d030d484..9037ed44f9 100644
--- a/tests/cfail/race-1.rs
+++ b/tests/cfail/race-1.rs
@@ -7,17 +7,38 @@ static R1: Resource<i32, C2> = Resource::new(0);
 fn j1(prio: P1) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R1, |ceil| {
-        let r1 = R1.borrow(&prio, ceil);
+    ceil.raise(
+        &R1, |ceil| {
+            let r1 = R1.borrow(&prio, ceil);
 
-        // Would preempt this critical section
-        // rtfm::request(j2);
-    });
+            // `j2` preempts this critical section
+            rtfm::request(j2);
+        }
+    );
 }
 
-fn j2(prio: P3) {
-    rtfm::critical(|ceil| {
-        let r1 = R1.borrow(&prio, &ceil);
-        //~^ error
-    });
+fn j2(_task: Task, prio: P3) {
+    rtfm::critical(
+        |ceil| {
+            // OK  C2 (R1's ceiling) <= C16 (system ceiling)
+            // BAD C2 (R1's ceiling) <  P3 (j2's priority)
+            let r1 = R1.borrow(&prio, &ceil);
+            //~^ error
+        },
+    );
+}
+
+// glue
+extern crate cortex_m;
+
+use cortex_m::ctxt::Context;
+use cortex_m::interrupt::Nr;
+
+struct Task;
+
+unsafe impl Context for Task {}
+unsafe impl Nr for Task {
+    fn nr(&self) -> u8 {
+        0
+    }
 }
diff --git a/tests/cfail/race-2.rs b/tests/cfail/race-2.rs
index 55dedb6ee5..6bd957e5dc 100644
--- a/tests/cfail/race-2.rs
+++ b/tests/cfail/race-2.rs
@@ -8,21 +8,40 @@ static R2: Resource<i32, C4> = Resource::new(0);
 fn j1(prio: P1) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R1, |ceil| {
-        let r1 = R1.borrow(&prio, ceil);
+    ceil.raise(
+        &R1, |ceil| {
+            let r1 = R1.borrow(&prio, ceil);
 
-        // Would preempt this critical section
-        // rtfm::request(j2);
-    });
+            // `j2` preempts this critical section
+            rtfm::request(j2);
+        }
+    );
 }
 
-fn j2(prio: P3) {
+fn j2(_task: Task, prio: P3) {
     let ceil = prio.as_ceiling();
 
-    ceil.raise(&R2, |ceil| {
-        // OK  C2 (R1's ceiling) <= C4 (system ceiling)
-        // BAD C2 (R1's ceiling) <  P3 (j2's priority)
-        let r1 = R1.borrow(&prio, ceil);
-        //~^ error
-    });
+    ceil.raise(
+        &R2, |ceil| {
+            // OK  C2 (R1's ceiling) <= C4 (system ceiling)
+            // BAD C2 (R1's ceiling) <  P3 (j2's priority)
+            let r1 = R1.borrow(&prio, ceil);
+            //~^ error
+        }
+    );
+}
+
+// glue
+extern crate cortex_m;
+
+use cortex_m::ctxt::Context;
+use cortex_m::interrupt::Nr;
+
+struct Task;
+
+unsafe impl Context for Task {}
+unsafe impl Nr for Task {
+    fn nr(&self) -> u8 {
+        0
+    }
 }
diff --git a/tests/cfail/tasks-p0.rs b/tests/cfail/tasks-p0.rs
index f1e83a378d..4db3d3895e 100644
--- a/tests/cfail/tasks-p0.rs
+++ b/tests/cfail/tasks-p0.rs
@@ -2,15 +2,14 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
 use rtfm::{C16, P0, P1};
 use device::interrupt::Exti0;
 
-/// Tasks can't have priority 0. Only idle has priority 0
+// WRONG: Tasks can't have a priority of 0.
+// Only idle and init can have a priority of 0.
 tasks!(device, {
     j1: (Exti0, P0),
 });
@@ -23,6 +22,10 @@ fn idle(_: P0) -> ! {
 
 fn j1(_task: Exti0, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
+
 mod device {
     pub mod interrupt {
         use cortex_m::interrupt::Nr;
diff --git a/tests/cfail/tasks-same-handler.rs b/tests/cfail/tasks-same-handler.rs
index 662a67db4a..89e20121bf 100644
--- a/tests/cfail/tasks-same-handler.rs
+++ b/tests/cfail/tasks-same-handler.rs
@@ -2,8 +2,6 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
@@ -26,6 +24,9 @@ fn j1(_task: Exti0, _prio: P1) {}
 
 fn j2(_task: Exti0, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
 
 mod device {
     pub mod interrupt {
diff --git a/tests/cfail/tasks-wrong-idle.rs b/tests/cfail/tasks-wrong-idle.rs
index 77afef6b3f..4ee910ee84 100644
--- a/tests/cfail/tasks-wrong-idle.rs
+++ b/tests/cfail/tasks-wrong-idle.rs
@@ -2,15 +2,12 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
 use device::interrupt::Exti0;
 use rtfm::{C16, P0, P1};
 
-/// Tasks can't have priority 0. Only idle has priority 0
 tasks!(device, {
     j1: (Exti0, P1),
 });
@@ -24,6 +21,10 @@ fn idle(_: P1) -> ! {
 
 fn j1(_task: Exti0, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
+
 mod device {
     pub mod interrupt {
         use cortex_m::interrupt::Nr;
diff --git a/tests/cfail/tasks-wrong-init.rs b/tests/cfail/tasks-wrong-init.rs
index 8b8359c40a..0f6e1c1e1c 100644
--- a/tests/cfail/tasks-wrong-init.rs
+++ b/tests/cfail/tasks-wrong-init.rs
@@ -2,8 +2,6 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
@@ -23,6 +21,10 @@ fn idle(_: P0) -> ! {
 
 fn j1(_task: Exti0, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
+
 mod device {
     pub mod interrupt {
         use cortex_m::interrupt::Nr;
diff --git a/tests/cfail/tasks-wrong-priority.rs b/tests/cfail/tasks-wrong-priority.rs
index 08deef32e9..75cbc0cc40 100644
--- a/tests/cfail/tasks-wrong-priority.rs
+++ b/tests/cfail/tasks-wrong-priority.rs
@@ -2,8 +2,6 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
@@ -23,6 +21,10 @@ fn idle(_: P0) -> ! {
 // Wrong priority token. Declared P1, got P2
 fn j1(_task: Exti1, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
+
 mod device {
     pub mod interrupt {
         use cortex_m::interrupt::Nr;
diff --git a/tests/cfail/tasks-wrong-task.rs b/tests/cfail/tasks-wrong-task.rs
index 15bd7764cd..0200da2d18 100644
--- a/tests/cfail/tasks-wrong-task.rs
+++ b/tests/cfail/tasks-wrong-task.rs
@@ -2,8 +2,6 @@
 
 #![feature(used)]
 
-extern crate core;
-extern crate cortex_m;
 #[macro_use]
 extern crate cortex_m_rtfm as rtfm;
 
@@ -23,6 +21,10 @@ fn idle(_: P0) -> ! {
 // Wrong task token. Declared Exti0, got Exti1
 fn j1(_task: Exti1, _prio: P1) {}
 
+// fake device crate
+extern crate core;
+extern crate cortex_m;
+
 mod device {
     pub mod interrupt {
         use cortex_m::interrupt::Nr;