Specialization feature in nightly

libafl/Cargo.toml

@@ -30,7 +30,7 @@ llmp_debug = [] # Enables debug output for LLMP
 llmp_small_maps = [] # reduces initial map size for llmp
 
 [build-dependencies]
-rustc_version = "0.4"
+rustversion = "1.0"
 
 [dev-dependencies]
 criterion = "0.3" # Benchmarking

libafl/build.rs

@@ -0,0 +1,7 @@
+#[rustversion::nightly]
+fn main() {
+    println!("cargo:rustc-cfg=unstable_feature");
+}
+
+#[rustversion::not(nightly)]
+fn main() {}

libafl/src/lib.rs

@@ -3,7 +3,7 @@ Welcome to `LibAFL`
 */
 
 #![cfg_attr(not(feature = "std"), no_std)]
-#![cfg_attr(feature = "RUSTC_IS_NIGHTLY", feature(min_specialization))]
+#![cfg_attr(unstable_feature, feature(specialization))]
 #![deny(rustdoc::broken_intra_doc_links)]
 #![deny(clippy::pedantic)]
 #![allow(