From 06c1e2f9b47b5bc9de049e1e1edfed27d8dd2c58 Mon Sep 17 00:00:00 2001
From: Jorge Aparicio <jorge@japaric.io>
Date: Sun, 16 Dec 2018 19:34:16 +0100
Subject: [PATCH] note that the timer queue is not supported on ARMv6-M

---
 CHANGELOG.md        |  3 +--
 README.md           |  4 +++-
 book/src/preface.md |  4 ++--
 build.rs            |  4 ++++
 ci/script.sh        | 26 ++++++++++++++++++--------
 src/lib.rs          |  5 +++++
 6 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e7fc88a48f..6b643f0a54 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,8 +9,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 
-- This crate now compiles on 1.31-beta and will compile on the stable 1.31
-  release.
+- This crate now compiles on stable 1.31.
 
 - [breaking-change] The `app!` macro has been transformed into an attribute. See
   the documentation for details.
diff --git a/README.md b/README.md
index 6c78e8bd7c..367a99275e 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,9 @@ behave the way you expect please open [an issue]!
 - **Highly efficient memory usage**: All the tasks share a single call stack and
   there's no hard dependency on a dynamic memory allocator.
 
-- **All Cortex-M devices are fully supported**.
+- **All Cortex-M devices are supported**. The core features of RTFM are
+  supported on all Cortex-M devices. The timer queue is currently only supported
+  on ARMv7-M devices.
 
 - This task model is amenable to known WCET (Worst Case Execution Time) analysis
   and scheduling analysis techniques. (Though we haven't yet developed Rust
diff --git a/book/src/preface.md b/book/src/preface.md
index c041ef5fa9..fe4ad620d3 100644
--- a/book/src/preface.md
+++ b/book/src/preface.md
@@ -7,6 +7,6 @@
 This book contains user level documentation for the Real Time For the Masses
 (RTFM) framework. The API reference can be found [here](../api/rtfm/index.html).
 
-{{#include ../../README.md:5:53}}
+{{#include ../../README.md:5:55}}
 
-{{#include ../../README.md:59:}}
+{{#include ../../README.md:61:}}
diff --git a/build.rs b/build.rs
index b29f0bd681..2419b4eb84 100644
--- a/build.rs
+++ b/build.rs
@@ -3,6 +3,10 @@ use std::env;
 fn main() {
     let target = env::var("TARGET").unwrap();
 
+    if target.starts_with("thumbv6m") {
+        println!("cargo:rustc-cfg=armv6m")
+    }
+
     if target.starts_with("thumbv7m") | target.starts_with("thumbv7em") {
         println!("cargo:rustc-cfg=armv7m")
     }
diff --git a/ci/script.sh b/ci/script.sh
index 20394d5cdc..0244c58171 100644
--- a/ci/script.sh
+++ b/ci/script.sh
@@ -12,11 +12,17 @@ main() {
         esac
 
         cargo check --target $T
-        cargo check --features timer-queue --target $T
+        if [ $TARGET != thumbv6m-none-eabi ]; then
+            cargo check --features timer-queue --target $T
+        fi
 
-        if [ $TRAVIS_RUST_VERSION = beta ]; then
+        if [ $TRAVIS_RUST_VERSION != nightly ]; then
             rm -f .cargo/config
-            cargo doc --features timer-queue
+            if [ $TARGET != thumbv6m-none-eabi ]; then
+                cargo doc --features timer-queue
+            else
+                cargo doc
+            fi
             ( cd book && mdbook build )
 
             local td=$(mktemp -d)
@@ -33,7 +39,9 @@ main() {
     fi
 
     cargo check --target $T --examples
-    cargo check --features timer-queue --target $T --examples
+    if [ $TARGET != thumbv6m-none-eabi ]; then
+        cargo check --features timer-queue --target $T --examples
+    fi
 
     # run-pass tests
     case $T in
@@ -76,11 +84,13 @@ main() {
                         diff -u ci/expected/$ex.run -
                 fi
 
-                cargo run --features timer-queue --example $ex --target $T | \
-                    diff -u ci/expected/$ex.run -
+                if [ $TARGET != thumbv6m-none-eabi ]; then
+                    cargo run --features timer-queue --example $ex --target $T | \
+                        diff -u ci/expected/$ex.run -
 
-                cargo run --features timer-queue --example $ex --target $T --release | \
-                    diff -u ci/expected/$ex.run -
+                    cargo run --features timer-queue --example $ex --target $T --release | \
+                        diff -u ci/expected/$ex.run -
+                fi
             done
     esac
 }
diff --git a/src/lib.rs b/src/lib.rs
index 213037b7e5..ba60078d7d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -44,6 +44,11 @@ pub mod export;
 #[cfg(feature = "timer-queue")]
 mod tq;
 
+#[cfg(all(feature = "timer-queue", armv6m))]
+compile_error!(
+    "The `timer-queue` feature is currently not supported on ARMv6-M (`thumbv6m-none-eabi`)"
+);
+
 /// Core peripherals
 ///
 /// This is `cortex_m::Peripherals` minus the peripherals that the RTFM runtime uses