Auto merge of #146255 - fmease:rollup-1v0kp8i, r=fmease

Rollup of 11 pull requests

Successful merges:

 - #138944 (Add `__isPlatformVersionAtLeast` and `__isOSVersionAtLeast` symbols)
 - #139113 (unstable book: in a sanitizer example, check the code)
 - #145735 (style-guide: Document absence of trailing whitespace)
 - #146041 (tidy: --bless now makes escheck run with --fix)
 - #146144 (compiler: Apply target features to the entry function)
 - #146225 (Simplify `{f16, f32, f64, f128}::midpoint()`)
 - #146234 (change file-is-generated doc comment to inner)
 - #146241 (rustc_infer: change top-level doc comment to inner)
 - #146242 (Ensure that `--html-after-content` option is used to check `scrape_examples_ice` rustdoc GUI test)
 - #146243 (remove couple of redundant clones)
 - #146250 (Bump stage0 rustfmt)

Failed merges:

 - #146200 (Simplify rustdoc-gui tester by calling directly browser-ui-test)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -296,6 +296,19 @@ pub(crate) fn tune_cpu_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribu
         .map(|tune_cpu| llvm::CreateAttrStringValue(cx.llcx, "tune-cpu", tune_cpu))
 }
 
+/// Get the `target-features` LLVM attribute.
+pub(crate) fn target_features_attr<'ll>(
+    cx: &CodegenCx<'ll, '_>,
+    function_features: Vec<String>,
+) -> Option<&'ll Attribute> {
+    let global_features = cx.tcx.global_backend_features(()).iter().map(String::as_str);
+    let function_features = function_features.iter().map(String::as_str);
+    let target_features =
+        global_features.chain(function_features).intersperse(",").collect::<String>();
+    (!target_features.is_empty())
+        .then(|| llvm::CreateAttrStringValue(cx.llcx, "target-features", &target_features))
+}
+
 /// Get the `NonLazyBind` LLVM attribute,
 /// if the codegen options allow skipping the PLT.
 pub(crate) fn non_lazy_bind_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
@@ -523,14 +536,7 @@ pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
         }
     }
 
-    let global_features = cx.tcx.global_backend_features(()).iter().map(|s| s.as_str());
-    let function_features = function_features.iter().map(|s| s.as_str());
-    let target_features: String =
-        global_features.chain(function_features).intersperse(",").collect();
-
-    if !target_features.is_empty() {
-        to_add.push(llvm::CreateAttrStringValue(cx.llcx, "target-features", &target_features));
-    }
+    to_add.extend(target_features_attr(cx, function_features));
 
     attributes::apply_to_llfn(llfn, Function, &to_add);
 }

compiler/rustc_codegen_llvm/src/context.rs

@@ -853,15 +853,21 @@ impl<'ll, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     fn declare_c_main(&self, fn_type: Self::Type) -> Option<Self::Function> {
         let entry_name = self.sess().target.entry_name.as_ref();
         if self.get_declared_value(entry_name).is_none() {
-            Some(self.declare_entry_fn(
+            let llfn = self.declare_entry_fn(
                 entry_name,
                 llvm::CallConv::from_conv(
                     self.sess().target.entry_abi,
                     self.sess().target.arch.borrow(),
                 ),
                 llvm::UnnamedAddr::Global,
                 fn_type,
-            ))
+            );
+            attributes::apply_to_llfn(
+                llfn,
+                llvm::AttributePlace::Function,
+                attributes::target_features_attr(self, vec![]).as_slice(),
+            );
+            Some(llfn)
         } else {
             // If the symbol already exists, it is an error: for example, the user wrote
             // #[no_mangle] extern "C" fn main(..) {..}

compiler/rustc_codegen_ssa/src/lib.rs

@@ -119,7 +119,7 @@ impl<M> ModuleCodegen<M> {
         });
 
         CompiledModule {
-            name: self.name.clone(),
+            name: self.name,
             object,
             dwarf_object,
             bytecode,

compiler/rustc_infer/src/infer/context.rs

@@ -1,4 +1,4 @@
-///! Definition of `InferCtxtLike` from the librarified type layer.
+//! Definition of `InferCtxtLike` from the librarified type layer.
 use rustc_hir::def_id::DefId;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::relate::RelateResult;

compiler/rustc_mir_transform/src/coverage/expansion.rs

@@ -82,7 +82,7 @@ impl ExpnNode {
         Self {
             expn_id,
 
-            expn_kind: expn_data.kind.clone(),
+            expn_kind: expn_data.kind,
             call_site,
             call_site_expn_id,
 

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -3099,7 +3099,7 @@ impl<'ast, 'ra, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
                 |err, _, span, message, suggestion, span_suggs| {
                     err.multipart_suggestion_verbose(
                         message,
-                        std::iter::once((span, suggestion)).chain(span_suggs.clone()).collect(),
+                        std::iter::once((span, suggestion)).chain(span_suggs).collect(),
                         Applicability::MaybeIncorrect,
                     );
                     true

compiler/rustc_symbol_mangling/src/v0.rs

@@ -82,9 +82,13 @@ pub(super) fn mangle<'tcx>(
 }
 
 pub fn mangle_internal_symbol<'tcx>(tcx: TyCtxt<'tcx>, item_name: &str) -> String {
-    if item_name == "rust_eh_personality" {
+    match item_name {
         // rust_eh_personality must not be renamed as LLVM hard-codes the name
-        return "rust_eh_personality".to_owned();
+        "rust_eh_personality" => return item_name.to_owned(),
+        // Apple availability symbols need to not be mangled to be usable by
+        // C/Objective-C code.
+        "__isPlatformVersionAtLeast" | "__isOSVersionAtLeast" => return item_name.to_owned(),
+        _ => {}
     }
 
     let prefix = "_R";

compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs

@@ -318,7 +318,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                     let (expected, found) = if expected_str == found_str {
                         (join_path_syms(&expected_abs), join_path_syms(&found_abs))
                     } else {
-                        (expected_str.clone(), found_str.clone())
+                        (expected_str, found_str)
                     };
 
                     // We've displayed "expected `a::b`, found `a::b`". We add context to

library/core/src/num/f128.rs

@@ -832,7 +832,6 @@ impl f128 {
     #[unstable(feature = "f128", issue = "116909")]
     #[rustc_const_unstable(feature = "f128", issue = "116909")]
     pub const fn midpoint(self, other: f128) -> f128 {
-        const LO: f128 = f128::MIN_POSITIVE * 2.;
         const HI: f128 = f128::MAX / 2.;
 
         let (a, b) = (self, other);
@@ -842,14 +841,7 @@ impl f128 {
         if abs_a <= HI && abs_b <= HI {
             // Overflow is impossible
             (a + b) / 2.
-        } else if abs_a < LO {
-            // Not safe to halve `a` (would underflow)
-            a + (b / 2.)
-        } else if abs_b < LO {
-            // Not safe to halve `b` (would underflow)
-            (a / 2.) + b
         } else {
-            // Safe to halve `a` and `b`
             (a / 2.) + (b / 2.)
         }
     }

library/core/src/num/f16.rs

@@ -820,7 +820,6 @@ impl f16 {
     #[unstable(feature = "f16", issue = "116909")]
     #[rustc_const_unstable(feature = "f16", issue = "116909")]
     pub const fn midpoint(self, other: f16) -> f16 {
-        const LO: f16 = f16::MIN_POSITIVE * 2.;
         const HI: f16 = f16::MAX / 2.;
 
         let (a, b) = (self, other);
@@ -830,14 +829,7 @@ impl f16 {
         if abs_a <= HI && abs_b <= HI {
             // Overflow is impossible
             (a + b) / 2.
-        } else if abs_a < LO {
-            // Not safe to halve `a` (would underflow)
-            a + (b / 2.)
-        } else if abs_b < LO {
-            // Not safe to halve `b` (would underflow)
-            (a / 2.) + b
         } else {
-            // Safe to halve `a` and `b`
             (a / 2.) + (b / 2.)
         }
     }