Move more to the lints table

Author: cuviper

Cargo.toml

@@ -67,5 +67,10 @@ private-interfaces = "deny"
 unnameable-types = "deny"
 unreachable-pub = "deny"
 
+# We *mostly* avoid unsafe code, but there are a few fine-grained cases allowed
+unsafe-code = "deny"
+
+rust-2018-idioms = "warn"
+
 [lints.clippy]
 style = "allow"

benches/faststring.rs

@@ -33,8 +33,10 @@ impl<'a, S> From<&'a S> for &'a OneShot<str>
 where
     S: AsRef<str>,
 {
+    #[allow(unsafe_code)]
     fn from(s: &'a S) -> Self {
         let s: &str = s.as_ref();
+        // SAFETY: OneShot is a `repr(transparent)` wrapper
         unsafe { &*(s as *const str as *const OneShot<str>) }
     }
 }

src/lib.rs

@@ -1,6 +1,3 @@
-// We *mostly* avoid unsafe code, but `Slice` allows it for DST casting.
-#![deny(unsafe_code)]
-#![warn(rust_2018_idioms)]
 #![no_std]
 
 //! [`IndexMap`] is a hash table where the iteration order of the key-value