Fix some clippy warnings (#1277)

cranelift/codegen/src/binemit/memorysink.rs

@@ -46,6 +46,8 @@ pub struct MemoryCodeSink<'a> {
 impl<'a> MemoryCodeSink<'a> {
     /// Create a new memory code sink that writes a function to the memory pointed to by `data`.
     ///
+    /// # Safety
+    ///
     /// This function is unsafe since `MemoryCodeSink` does not perform bounds checking on the
     /// memory buffer, and it can't guarantee that the `data` pointer is valid.
     pub unsafe fn new(

cranelift/codegen/src/context.rs

@@ -175,6 +175,8 @@ impl Context {
     ///
     /// The machine code is not relocated. Instead, any relocations are emitted into `relocs`.
     ///
+    /// # Safety
+    ///
     /// This function is unsafe since it does not perform bounds checking on the memory buffer,
     /// and it can't guarantee that the `mem` pointer is valid.
     ///

cranelift/codegen/src/isa/mod.rs

@@ -22,7 +22,6 @@
 //! ```
 //! # extern crate cranelift_codegen;
 //! # #[macro_use] extern crate target_lexicon;
-//! # fn main() {
 //! use cranelift_codegen::isa;
 //! use cranelift_codegen::settings::{self, Configurable};
 //! use std::str::FromStr;
@@ -40,7 +39,6 @@
 //!         let isa = isa_builder.finish(shared_flags);
 //!     }
 //! }
-//! # }
 //! ```
 //!
 //! The configured target ISA trait object is a `Box<TargetIsa>` which can be used for multiple

cranelift/codegen/src/isa/x86/abi.rs

@@ -938,7 +938,7 @@ fn insert_common_epilogue(
             .entry(fp_pop_inst)
             .and_modify(|insts| {
                 *insts = insts
-                    .into_iter()
+                    .iter()
                     .cloned()
                     .chain(std::iter::once(new_cfa))
                     .collect::<Box<[_]>>();

cranelift/codegen/src/licm.rs

@@ -73,7 +73,6 @@ fn create_pre_header(
     let pool = &mut ListPool::<Value>::new();
     let header_args_values = func.dfg.ebb_params(header).to_vec();
     let header_args_types: Vec<Type> = header_args_values
-        .clone()
         .into_iter()
         .map(|val| func.dfg.value_type(val))
         .collect();

cranelift/codegen/src/verifier/mod.rs

@@ -107,7 +107,7 @@ pub struct VerifierError {
 fn format_context(context: &Option<String>) -> String {
     match context {
         None => "".to_string(),
-        Some(c) => format!(" ({})", c).to_string(),
+        Some(c) => format!(" ({})", c),
     }
 }