Auto merge of #126736 - matthiaskrgr:rollup-rb20oe3, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #126380 (Add std Xtensa targets support)
 - #126636 (Resolve Clippy `f16` and `f128` `unimplemented!`/`FIXME`s )
 - #126659 (More status-quo tests for the `#[coverage(..)]` attribute)
 - #126711 (Make Option::as_[mut_]slice const)
 - #126717 (Clean up some comments near `use` declarations)
 - #126719 (Fix assertion failure for some `Expect` diagnostics.)
 - #126730 (Add opaque type corner case test)

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

Author: bors

Cargo.lock

@@ -709,6 +709,7 @@ dependencies = [
  "clippy_config",
  "itertools 0.12.1",
  "rustc-semver",
+ "rustc_apfloat",
 ]
 
 [[package]]

compiler/rustc_builtin_macros/src/test.rs

@@ -1,6 +1,7 @@
+//! The expansion from a test function to the appropriate test struct for libtest
+//! Ideally, this code would be in libtest but for efficiency and error messages it lives here.
+
 use crate::errors;
-/// The expansion from a test function to the appropriate test struct for libtest
-/// Ideally, this code would be in libtest but for efficiency and error messages it lives here.
 use crate::util::{check_builtin_macro_attribute, warn_on_duplicate_attribute};
 use rustc_ast::ptr::P;
 use rustc_ast::{self as ast, attr, GenericParamKind};

compiler/rustc_codegen_gcc/tests/lang_tests_common.rs

@@ -1,4 +1,5 @@
 //! The common code for `tests/lang_tests_*.rs`
+
 use std::{
     env::{self, current_dir},
     path::{Path, PathBuf},

compiler/rustc_codegen_ssa/src/mir/locals.rs

@@ -1,6 +1,7 @@
 //! Locals are in a private module as updating `LocalRef::Operand` has to
 //! be careful wrt to subtyping. To deal with this we only allow updates by using
 //! `FunctionCx::overwrite_local` which handles it automatically.
+
 use crate::mir::{FunctionCx, LocalRef};
 use crate::traits::BuilderMethods;
 use rustc_index::IndexVec;

compiler/rustc_data_structures/src/base_n.rs

@@ -1,5 +1,6 @@
-/// Converts unsigned integers into a string representation with some base.
-/// Bases up to and including 36 can be used for case-insensitive things.
+//! Converts unsigned integers into a string representation with some base.
+//! Bases up to and including 36 can be used for case-insensitive things.
+
 use std::ascii;
 use std::fmt;
 

compiler/rustc_errors/src/lib.rs

@@ -1437,6 +1437,24 @@ impl DiagCtxtInner {
 
     // Return value is only `Some` if the level is `Error` or `DelayedBug`.
     fn emit_diagnostic(&mut self, mut diagnostic: DiagInner) -> Option<ErrorGuaranteed> {
+        match diagnostic.level {
+            Expect(expect_id) | ForceWarning(Some(expect_id)) => {
+                // The `LintExpectationId` can be stable or unstable depending on when it was
+                // created. Diagnostics created before the definition of `HirId`s are unstable and
+                // can not yet be stored. Instead, they are buffered until the `LintExpectationId`
+                // is replaced by a stable one by the `LintLevelsBuilder`.
+                if let LintExpectationId::Unstable { .. } = expect_id {
+                    // We don't call TRACK_DIAGNOSTIC because we wait for the
+                    // unstable ID to be updated, whereupon the diagnostic will be
+                    // passed into this method again.
+                    self.unstable_expect_diagnostics.push(diagnostic);
+                    return None;
+                }
+                // Continue through to the `Expect`/`ForceWarning` case below.
+            }
+            _ => {}
+        }
+
         if diagnostic.has_future_breakage() {
             // Future breakages aren't emitted if they're `Level::Allow`,
             // but they still need to be constructed and stashed below,
@@ -1512,16 +1530,8 @@ impl DiagCtxtInner {
                 return None;
             }
             Expect(expect_id) | ForceWarning(Some(expect_id)) => {
-                // Diagnostics created before the definition of `HirId`s are
-                // unstable and can not yet be stored. Instead, they are
-                // buffered until the `LintExpectationId` is replaced by a
-                // stable one by the `LintLevelsBuilder`.
                 if let LintExpectationId::Unstable { .. } = expect_id {
-                    // We don't call TRACK_DIAGNOSTIC because we wait for the
-                    // unstable ID to be updated, whereupon the diagnostic will
-                    // be passed into this method again.
-                    self.unstable_expect_diagnostics.push(diagnostic);
-                    return None;
+                    unreachable!(); // this case was handled at the top of this function
                 }
                 self.fulfilled_expectations.insert(expect_id.normalize());
                 if let Expect(_) = diagnostic.level {

compiler/rustc_errors/src/markdown/mod.rs

@@ -1,6 +1,7 @@
 //! A simple markdown parser that can write formatted text to the terminal
 //!
 //! Entrypoint is `MdStream::parse_str(...)`
+
 use std::io;
 
 use termcolor::{Buffer, BufferWriter, ColorChoice};

compiler/rustc_expand/src/mbe/macro_check.rs

@@ -104,6 +104,7 @@
 //! Kleene operators under which a meta-variable is repeating is the concatenation of the stacks
 //! stored when entering a macro definition starting from the state in which the meta-variable is
 //! bound.
+
 use crate::errors;
 use crate::mbe::{KleeneToken, TokenTree};
 

compiler/rustc_fs_util/src/lib.rs

@@ -1,9 +1,7 @@
-// tidy-alphabetical-start
 use std::ffi::CString;
 use std::fs;
 use std::io;
 use std::path::{absolute, Path, PathBuf};
-// tidy-alphabetical-end
 
 // Unfortunately, on windows, it looks like msvcrt.dll is silently translating
 // verbatim paths under the hood to non-verbatim paths! This manifests itself as

compiler/rustc_hir_analysis/src/check/dropck.rs

@@ -1,6 +1,7 @@
 // FIXME(@lcnr): Move this module out of `rustc_hir_analysis`.
 //
 // We don't do any drop checking during hir typeck.
+
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{codes::*, struct_span_code_err, ErrorGuaranteed};
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;