Fix wasm benches on nightly (#93)

.travis.yml

@@ -22,7 +22,7 @@ install:
 - command -v cargo-deadlinks &> /dev/null || cargo install cargo-deadlinks
 - if [ "$TRAVIS_RUST_VERSION" == "nightly" ]; then rustup target add wasm32-unknown-unknown; fi
 script:
-# Make sure fuzz targets are not broken.
+# Make sure nightly targets are not broken.
 - if [ "$TRAVIS_RUST_VERSION" == "nightly" ]; then cargo check --tests --manifest-path=fuzz/Cargo.toml; fi
 - if [ "$TRAVIS_RUST_VERSION" == "nightly" ]; then cargo check --benches --manifest-path=benches/Cargo.toml; fi
 - ./test.sh

benches/wasm-kernel/src/lib.rs

@@ -1,6 +1,7 @@
 #![no_std]
 #![feature(lang_items)]
 #![feature(core_intrinsics)]
+#![feature(panic_implementation)]
 
 extern crate rlibc;
 extern crate tiny_keccak;
@@ -8,13 +9,8 @@ extern crate tiny_keccak;
 use tiny_keccak::Keccak;
 
 #[no_mangle]
-#[lang = "panic_fmt"]
-pub extern "C" fn panic_fmt(
-	_args: ::core::fmt::Arguments,
-	_file: &'static str,
-	_line: u32,
-	_col: u32,
-) -> ! {
+#[panic_implementation]
+pub fn panic_fmt(_info: &::core::panic::PanicInfo) -> ! {
 	use core::intrinsics;
 	unsafe {
 		intrinsics::abort();