Add compatibilty with rust-stable.

  * Add feature flag for const-fn functionality, which simplifies some
    things and lets this crate run on architectures where atomic CAS
    isn't available (e.g., thumbv6).

  * Remove `const fn` where necessary to compile under rust-stable.

  * BREAKING CHANGE - Change signature of `Handler::replace` to take a
    mutable borrow. This is required because the underlying type is
    now a NonNull, which needs `mut`. The old behavior was never
    desired, but a consequence of trying to avoid `Option` by using a
    default handler.

  * Use lazy_static crate for initialization of Handler/HandlerArray.

  * Specify Sync for Handler. This is not amazing, since it isn't, but
    it's necessary for initialization in static contexts inside
    `lazy_static`. This should be fine, because any actual
    manipulation of the handler is done in unsafe functions.

1 files changed, 6 insertions, 1 deletions

diff --git a/examples/scope.rs b/examples/scope.rs
index cd17570..8df0702 100644
--- a/examples/scope.rs
+++ b/examples/scope.rs
@@ -1,6 +1,11 @@
 use clint::HandlerArray;
 
-static HANDLERS: HandlerArray = HandlerArray::new();
+#[macro_use]
+extern crate lazy_static;
+
+lazy_static! {
+    static ref HANDLERS: HandlerArray<'static> = HandlerArray::new();
+}
 
 fn main() {
     let mut cl = || println!("whoa!");