Trivial clippy fixes after the update to nightly-2022-10-08.

c2rust-ast-exporter/build.rs

@@ -83,7 +83,7 @@ fn generate_bindings() -> Result<(), &'static str> {
         .clang_arg("-xc++")
         // Finish the builder and generate the bindings.
         .generate()
-        .or(Err("Unable to generate AST bindings"))?;
+        .map_err(|_| "Unable to generate AST bindings")?;
 
     let cppbindings = bindgen::Builder::default()
         .header("src/ExportResult.hpp")
@@ -95,7 +95,7 @@ fn generate_bindings() -> Result<(), &'static str> {
         .clang_arg("-std=c++11")
         // Finish the builder and generate the bindings.
         .generate()
-        .or(Err("Unable to generate ExportResult bindings"))?;
+        .map_err(|_| "Unable to generate ExportResult bindings")?;
 
     // Write the bindings to the $OUT_DIR/bindings.rs file.
     let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());

c2rust-transpile/src/translator/atomics.rs

@@ -318,7 +318,7 @@ impl<'c> Translation<'c> {
         // Emit `atomic_cxchg(a0, a1, a2).idx`
         let atomic_cxchg = mk().abs_path_expr(vec!["core", "intrinsics", intrinsic_name]);
         let call = mk().call_expr(atomic_cxchg, vec![dst, old_val, src_val]);
-        let field_idx = if returns_val { 0 } else { 1 };
+        let field_idx = (!returns_val).into();
         let call_expr = mk().anon_field_expr(call, field_idx);
         self.convert_side_effects_expr(
             ctx,