[clippy] stricter lints

Cargo.toml

@@ -5,12 +5,17 @@ edition = "2021"
 
 [dependencies]
 
+[lints.rust]
+unsafe_code = "forbid"
+
 [lints.clippy]
-pedantic = "warn"
+pedantic = { level = "warn", priority = -1 }
+todo = "warn"
+unwrap_used = "warn"
 
 [profile.release]
 lto = true
 debug = false
 strip = true
-codegen-units = 1
 panic = "unwind"
+codegen-units = 1

src/sieve.rs

@@ -38,8 +38,8 @@ fn find_next_prime(nr: &mut u64, sieve: &mut [bool]) -> Option<u64> {
     None
 }
 
+#[allow(clippy::unwrap_used)]
 fn check_off_multiples_of_nr(nr: u64, sieve: &mut [bool]) {
-
     let nr = usize::try_from(nr).unwrap();
 
     sieve