don't lazily evaulate some trivial values for Option::None replacements (clippy::unnecessary_lazy_evaluations)

Author: matthiaskrgr

compiler/rustc_lint/src/builtin.rs

@@ -961,7 +961,7 @@ fn warn_if_doc(cx: &EarlyContext<'_>, node_span: Span, node_kind: &str, attrs: &
             continue;
         }
 
-        let span = sugared_span.take().unwrap_or_else(|| attr.span);
+        let span = sugared_span.take().unwrap_or(attr.span);
 
         if attr.is_doc_comment() || cx.sess().check_name(attr, sym::doc) {
             cx.struct_span_lint(UNUSED_DOC_COMMENTS, span, |lint| {

compiler/rustc_metadata/src/native_libs.rs

@@ -170,7 +170,7 @@ impl Collector<'tcx> {
             feature_err(
                 &self.tcx.sess.parse_sess,
                 sym::static_nobundle,
-                span.unwrap_or_else(|| rustc_span::DUMMY_SP),
+                span.unwrap_or(rustc_span::DUMMY_SP),
                 "kind=\"static-nobundle\" is unstable",
             )
             .emit();
@@ -179,7 +179,7 @@ impl Collector<'tcx> {
             feature_err(
                 &self.tcx.sess.parse_sess,
                 sym::raw_dylib,
-                span.unwrap_or_else(|| rustc_span::DUMMY_SP),
+                span.unwrap_or(rustc_span::DUMMY_SP),
                 "kind=\"raw-dylib\" is unstable",
             )
             .emit();

compiler/rustc_mir/src/dataflow/move_paths/builder.rs

@@ -480,10 +480,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
             };
             let base_ty = base_place.ty(self.builder.body, self.builder.tcx).ty;
             let len: u64 = match base_ty.kind() {
-                ty::Array(_, size) => {
-                    let length: u64 = size.eval_usize(self.builder.tcx, self.builder.param_env);
-                    length
-                }
+                ty::Array(_, size) => size.eval_usize(self.builder.tcx, self.builder.param_env),
                 _ => bug!("from_end: false slice pattern of non-array type"),
             };
             for offset in from..to {