WIP: Add `const-fn` feature to attempt support for stable toolchain.

To get this to work, either `FnMut` traits need to be allowed in
`const fn` in stable, or `Handler::new` needs to be non-`const`.

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 1079e1d..6d6f192 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,7 @@ cortex-m = "~0.6"
 
 [features]
 default = ["isr-32"]
+const-fn = []
 
 # Number of ISR closures to hold in a HandlerTable. This is pretty
 # clumsy, but doesn't require const generics.