switch to rustversion

libafl/Cargo.toml

@@ -9,7 +9,6 @@ readme = "../README.md"
 license = "MIT OR Apache-2.0"
 keywords = ["fuzzing", "testing", "security"]
 edition = "2021"
-build = "build.rs"
 
 [features]
 default = ["std", "derive", "llmp_compression", "rand_trait", "fork"]
@@ -43,6 +42,7 @@ num_cpus = "1.0" # cpu count, for llmp example
 serial_test = "0.5"
 
 [dependencies]
+rustversion = "1.0"
 tuple_list = { version = "0.1.3" }
 hashbrown =  { version = "0.11", features = ["serde", "ahash-compile-time-rng"], default-features=false } # A faster hashmap, nostd compatible
 num-traits = { version = "0.2", default-features = false }

libafl/build.rs

@@ -1,22 +0,0 @@
-//! special handling to build and link libafl
-
-use rustc_version::{version_meta, Channel};
-
-#[allow(clippy::ptr_arg, clippy::upper_case_acronyms)]
-fn main() {
-    // Set cfg flags depending on release channel
-    match version_meta().unwrap().channel {
-        Channel::Stable => {
-            println!("cargo:rustc-cfg=RUSTC_IS_STABLE");
-        }
-        Channel::Beta => {
-            println!("cargo:rustc-cfg=RUSTC_IS_BETA");
-        }
-        Channel::Nightly => {
-            println!("cargo:rustc-cfg=RUSTC_IS_NIGHTLY");
-        }
-        Channel::Dev => {
-            println!("cargo:rustc-cfg=RUSTC_IS_DEV");
-        }
-    }
-}

libafl/src/bolts/tuples.rs

@@ -6,7 +6,7 @@ use core::any::TypeId;
 
 use xxhash_rust::xxh3::xxh3_64;
 
-#[cfg(feature = "RUSTC_IS_NIGHTLY")]
+#[rustversion::nightly]
 /// From https://stackoverflow.com/a/60138532/7658998
 const fn type_eq<T: ?Sized, U: ?Sized>() -> bool {
     // Helper trait. `VALUE` is false, except for the specialization of the
@@ -28,7 +28,7 @@ const fn type_eq<T: ?Sized, U: ?Sized>() -> bool {
     <T as TypeEq<U>>::VALUE
 }
 
-#[cfg(not(feature = "RUSTC_IS_NIGHTLY"))]
+#[rustversion::not(nightly)]
 const fn type_eq<T: ?Sized, U: ?Sized>() -> bool {
     // BEWARE! This is not unsafe, it is SUPER UNSAFE
     true