Rollup of 11 pull requests

compiler/rustc_builtin_macros/src/assert.rs

@@ -1,8 +1,8 @@
 mod context;
 
-use rustc_ast::token::{self, Delimiter};
+use rustc_ast::token::Delimiter;
 use rustc_ast::tokenstream::{DelimSpan, TokenStream};
-use rustc_ast::{DelimArgs, Expr, ExprKind, MacCall, Path, PathSegment};
+use rustc_ast::{DelimArgs, Expr, ExprKind, MacCall, Path, PathSegment, UnOp, token};
 use rustc_ast_pretty::pprust;
 use rustc_errors::PResult;
 use rustc_expand::base::{DummyResult, ExpandResult, ExtCtxt, MacEager, MacroExpanderResult};
@@ -29,7 +29,7 @@ pub(crate) fn expand_assert<'cx>(
 
     // `core::panic` and `std::panic` are different macros, so we use call-site
     // context to pick up whichever is currently in scope.
-    let call_site_span = cx.with_call_site_ctxt(cond_expr.span);
+    let call_site_span = cx.with_call_site_ctxt(span);
 
     let panic_path = || {
         if use_panic_2021(span) {
@@ -63,7 +63,7 @@ pub(crate) fn expand_assert<'cx>(
                 }),
             })),
         );
-        assert_cond_check(cx, call_site_span, cond_expr, then)
+        expr_if_not(cx, call_site_span, cond_expr, then, None)
     }
     // If `generic_assert` is enabled, generates rich captured outputs
     //
@@ -88,33 +88,26 @@ pub(crate) fn expand_assert<'cx>(
                 )),
             )],
         );
-        assert_cond_check(cx, call_site_span, cond_expr, then)
+        expr_if_not(cx, call_site_span, cond_expr, then, None)
     };
 
     ExpandResult::Ready(MacEager::expr(expr))
 }
 
-/// `assert!($cond_expr, $custom_message)`
 struct Assert {
     cond_expr: Box<Expr>,
     custom_message: Option<TokenStream>,
 }
 
-/// `match <cond> { true => {} _ => <then> }`
-fn assert_cond_check(cx: &ExtCtxt<'_>, span: Span, cond: Box<Expr>, then: Box<Expr>) -> Box<Expr> {
-    // Instead of expanding to `if !<cond> { <then> }`, we expand to
-    // `match <cond> { true => {} _ => <then> }`.
-    // This allows us to always complain about mismatched types instead of "cannot apply unary
-    // operator `!` to type `X`" when passing an invalid `<cond>`, while also allowing `<cond>` to
-    // be `&true`.
-    let els = cx.expr_block(cx.block(span, thin_vec![]));
-    let mut arms = thin_vec![];
-    arms.push(cx.arm(span, cx.pat_lit(span, cx.expr_bool(span, true)), els));
-    arms.push(cx.arm(span, cx.pat_wild(span), then));
-
-    // We wrap the `match` in a statement to limit the length of any borrows introduced in the
-    // condition.
-    cx.expr_block(cx.block(span, [cx.stmt_expr(cx.expr_match(span, cond, arms))].into()))
+// if !{ ... } { ... } else { ... }
+fn expr_if_not(
+    cx: &ExtCtxt<'_>,
+    span: Span,
+    cond: Box<Expr>,
+    then: Box<Expr>,
+    els: Option<Box<Expr>>,
+) -> Box<Expr> {
+    cx.expr_if(span, cx.expr(span, ExprKind::Unary(UnOp::Not, cond)), then, els)
 }
 
 fn parse_assert<'a>(cx: &ExtCtxt<'a>, sp: Span, stream: TokenStream) -> PResult<'a, Assert> {

compiler/rustc_parse/src/parser/ty.rs

@@ -92,10 +92,10 @@ fn can_continue_type_after_non_fn_ident(t: &Token) -> bool {
 }
 
 fn can_begin_dyn_bound_in_edition_2015(t: &Token) -> bool {
-    // `Not`, `Tilde` & `Const` are deliberately not part of this list to
+    // `!`, `const`, `[`, `async` are deliberately not part of this list to
     // contain the number of potential regressions esp. in MBE code.
-    // `Const` would regress `rfc-2632-const-trait-impl/mbe-dyn-const-2015.rs`.
-    // `Not` would regress `dyn!(...)` macro calls in Rust 2015.
+    // `const` and `[` would regress UI test `macro-dyn-const-2015.rs`.
+    // `!` would regress `dyn!(...)` macro calls in Rust 2015.
     t.is_path_start()
         || t.is_lifetime()
         || t == &TokenKind::Question
@@ -1015,12 +1015,18 @@ impl<'a> Parser<'a> {
             || self.check(exp!(Tilde))
             || self.check_keyword(exp!(For))
             || self.check(exp!(OpenParen))
-            || self.check(exp!(OpenBracket))
+            || self.can_begin_maybe_const_bound()
             || self.check_keyword(exp!(Const))
             || self.check_keyword(exp!(Async))
             || self.check_keyword(exp!(Use))
     }
 
+    fn can_begin_maybe_const_bound(&mut self) -> bool {
+        self.check(exp!(OpenBracket))
+            && self.look_ahead(1, |t| t.is_keyword(kw::Const))
+            && self.look_ahead(2, |t| *t == token::CloseBracket)
+    }
+
     /// Parse a bound.
     ///
     /// ```ebnf
@@ -1199,10 +1205,7 @@ impl<'a> Parser<'a> {
             let span = tilde.to(self.prev_token.span);
             self.psess.gated_spans.gate(sym::const_trait_impl, span);
             BoundConstness::Maybe(span)
-        } else if self.check(exp!(OpenBracket))
-            && self.look_ahead(1, |t| t.is_keyword(kw::Const))
-            && self.look_ahead(2, |t| *t == token::CloseBracket)
-        {
+        } else if self.can_begin_maybe_const_bound() {
             let start = self.token.span;
             self.bump();
             self.expect_keyword(exp!(Const)).unwrap();

compiler/rustc_span/src/symbol.rs

@@ -7,7 +7,7 @@ use std::ops::Deref;
 use std::{fmt, str};
 
 use rustc_arena::DroplessArena;
-use rustc_data_structures::fx::FxIndexSet;
+use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_data_structures::stable_hasher::{
     HashStable, StableCompare, StableHasher, ToStableHashKey,
 };
@@ -2871,11 +2871,20 @@ impl Interner {
         let byte_strs = FxIndexSet::from_iter(
             init.iter().copied().chain(extra.iter().copied()).map(|str| str.as_bytes()),
         );
-        assert_eq!(
-            byte_strs.len(),
-            init.len() + extra.len(),
-            "duplicate symbols in the rustc symbol list and the extra symbols added by the driver",
-        );
+
+        // The order in which duplicates are reported is irrelevant.
+        #[expect(rustc::potential_query_instability)]
+        if byte_strs.len() != init.len() + extra.len() {
+            panic!(
+                "duplicate symbols in the rustc symbol list and the extra symbols added by the driver: {:?}",
+                FxHashSet::intersection(
+                    &init.iter().copied().collect(),
+                    &extra.iter().copied().collect(),
+                )
+                .collect::<Vec<_>>()
+            )
+        }
+
         Interner(Lock::new(InternerInner { arena: Default::default(), byte_strs }))
     }
 

compiler/rustc_target/src/target_features.rs

@@ -849,6 +849,7 @@ const IBMZ_FEATURES: &[(&str, Stability, ImpliedFeatures)] = &[
     ("miscellaneous-extensions-3", Unstable(sym::s390x_target_feature), &[]),
     ("miscellaneous-extensions-4", Unstable(sym::s390x_target_feature), &[]),
     ("nnp-assist", Unstable(sym::s390x_target_feature), &["vector"]),
+    ("soft-float", Forbidden { reason: "currently unsupported ABI-configuration feature" }, &[]),
     ("transactional-execution", Unstable(sym::s390x_target_feature), &[]),
     ("vector", Unstable(sym::s390x_target_feature), &[]),
     ("vector-enhancements-1", Unstable(sym::s390x_target_feature), &["vector"]),
@@ -1177,6 +1178,13 @@ impl Target {
                     _ => unreachable!(),
                 }
             }
+            "s390x" => {
+                // We don't currently support a softfloat target on this architecture.
+                // As usual, we have to reject swapping the `soft-float` target feature.
+                // The "vector" target feature does not affect the ABI for floats
+                // because the vector and float registers overlap.
+                FeatureConstraints { required: &[], incompatible: &["soft-float"] }
+            }
             _ => NOTHING,
         }
     }

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

@@ -1618,18 +1618,8 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
         {
             let e = self.tcx.erase_and_anonymize_regions(e);
             let f = self.tcx.erase_and_anonymize_regions(f);
-            let mut expected = with_forced_trimmed_paths!(e.sort_string(self.tcx));
-            let mut found = with_forced_trimmed_paths!(f.sort_string(self.tcx));
-            if let ObligationCauseCode::Pattern { span, .. } = cause.code()
-                && let Some(span) = span
-                && !span.from_expansion()
-                && cause.span.from_expansion()
-            {
-                // When the type error comes from a macro like `assert!()`, and we are pointing at
-                // code the user wrote the cause and effect are reversed as the expected value is
-                // what the macro expanded to.
-                (found, expected) = (expected, found);
-            }
+            let expected = with_forced_trimmed_paths!(e.sort_string(self.tcx));
+            let found = with_forced_trimmed_paths!(f.sort_string(self.tcx));
             if expected == found {
                 label_or_note(span, terr.to_string(self.tcx));
             } else {
@@ -2152,9 +2142,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     ) -> Option<(DiagStyledString, DiagStyledString)> {
         match values {
             ValuePairs::Regions(exp_found) => self.expected_found_str(exp_found),
-            ValuePairs::Terms(exp_found) => {
-                self.expected_found_str_term(cause, exp_found, long_ty_path)
-            }
+            ValuePairs::Terms(exp_found) => self.expected_found_str_term(exp_found, long_ty_path),
             ValuePairs::Aliases(exp_found) => self.expected_found_str(exp_found),
             ValuePairs::ExistentialTraitRef(exp_found) => self.expected_found_str(exp_found),
             ValuePairs::ExistentialProjection(exp_found) => self.expected_found_str(exp_found),
@@ -2193,35 +2181,15 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
 
     fn expected_found_str_term(
         &self,
-        cause: &ObligationCause<'tcx>,
         exp_found: ty::error::ExpectedFound<ty::Term<'tcx>>,
         long_ty_path: &mut Option<PathBuf>,
     ) -> Option<(DiagStyledString, DiagStyledString)> {
         let exp_found = self.resolve_vars_if_possible(exp_found);
         if exp_found.references_error() {
             return None;
         }
-        let (mut expected, mut found) = (exp_found.expected, exp_found.found);
-
-        if let ObligationCauseCode::Pattern { span, .. } = cause.code()
-            && let Some(span) = span
-            && !span.from_expansion()
-            && cause.span.from_expansion()
-        {
-            // When the type error comes from a macro like `assert!()`, and we are pointing at
-            // code the user wrote, the cause and effect are reversed as the expected value is
-            // what the macro expanded to. So if the user provided a `Type` when the macro is
-            // written in such a way that a `bool` was expected, we want to print:
-            // = note: expected `bool`
-            //            found `Type`"
-            // but as far as the compiler is concerned, after expansion what was expected was `Type`
-            // = note: expected `Type`
-            //            found `bool`"
-            // so we reverse them here to match user expectation.
-            (expected, found) = (found, expected);
-        }
 
-        Some(match (expected.kind(), found.kind()) {
+        Some(match (exp_found.expected.kind(), exp_found.found.kind()) {
             (ty::TermKind::Ty(expected), ty::TermKind::Ty(found)) => {
                 let (mut exp, mut fnd) = self.cmp(expected, found);
                 // Use the terminal width as the basis to determine when to compress the printed

library/core/src/ptr/const_ptr.rs

@@ -146,28 +146,7 @@ impl<T: PointeeSized> *const T {
         self as _
     }
 
-    /// Gets the "address" portion of the pointer.
-    ///
-    /// This is similar to `self as usize`, except that the [provenance][crate::ptr#provenance] of
-    /// the pointer is discarded and not [exposed][crate::ptr#exposed-provenance]. This means that
-    /// casting the returned address back to a pointer yields a [pointer without
-    /// provenance][without_provenance], which is undefined behavior to dereference. To properly
-    /// restore the lost information and obtain a dereferenceable pointer, use
-    /// [`with_addr`][pointer::with_addr] or [`map_addr`][pointer::map_addr].
-    ///
-    /// If using those APIs is not possible because there is no way to preserve a pointer with the
-    /// required provenance, then Strict Provenance might not be for you. Use pointer-integer casts
-    /// or [`expose_provenance`][pointer::expose_provenance] and [`with_exposed_provenance`][with_exposed_provenance]
-    /// instead. However, note that this makes your code less portable and less amenable to tools
-    /// that check for compliance with the Rust memory model.
-    ///
-    /// On most platforms this will produce a value with the same bytes as the original
-    /// pointer, because all the bytes are dedicated to describing the address.
-    /// Platforms which need to store additional information in the pointer may
-    /// perform a change of representation to produce a value containing only the address
-    /// portion of the pointer. What that means is up to the platform to define.
-    ///
-    /// This is a [Strict Provenance][crate::ptr#strict-provenance] API.
+    #[doc = include_str!("./docs/addr.md")]
     #[must_use]
     #[inline(always)]
     #[stable(feature = "strict_provenance", since = "1.84.0")]
@@ -254,23 +233,16 @@ impl<T: PointeeSized> *const T {
         (self.cast(), metadata(self))
     }
 
-    /// Returns `None` if the pointer is null, or else returns a shared reference to
-    /// the value wrapped in `Some`. If the value may be uninitialized, [`as_uninit_ref`]
-    /// must be used instead.
-    ///
-    /// [`as_uninit_ref`]: #method.as_uninit_ref
-    ///
-    /// # Safety
-    ///
-    /// When calling this method, you have to ensure that *either* the pointer is null *or*
-    /// the pointer is [convertible to a reference](crate::ptr#pointer-to-reference-conversion).
+    #[doc = include_str!("./docs/as_ref.md")]
     ///
-    /// # Panics during const evaluation
-    ///
-    /// This method will panic during const evaluation if the pointer cannot be
-    /// determined to be null or not. See [`is_null`] for more information.
+    /// ```
+    /// let ptr: *const u8 = &10u8 as *const u8;
     ///
-    /// [`is_null`]: #method.is_null
+    /// unsafe {
+    ///     let val_back = &*ptr;
+    ///     assert_eq!(val_back, &10);
+    /// }
+    /// ```
     ///
     /// # Examples
     ///
@@ -284,20 +256,9 @@ impl<T: PointeeSized> *const T {
     /// }
     /// ```
     ///
-    /// # Null-unchecked version
     ///
-    /// If you are sure the pointer can never be null and are looking for some kind of
-    /// `as_ref_unchecked` that returns the `&T` instead of `Option<&T>`, know that you can
-    /// dereference the pointer directly.
-    ///
-    /// ```
-    /// let ptr: *const u8 = &10u8 as *const u8;
-    ///
-    /// unsafe {
-    ///     let val_back = &*ptr;
-    ///     assert_eq!(val_back, &10);
-    /// }
-    /// ```
+    /// [`is_null`]: #method.is_null
+    /// [`as_uninit_ref`]: #method.as_uninit_ref
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
     #[rustc_const_stable(feature = "const_ptr_is_null", since = "1.84.0")]
     #[inline]
@@ -338,23 +299,10 @@ impl<T: PointeeSized> *const T {
         unsafe { &*self }
     }
 
-    /// Returns `None` if the pointer is null, or else returns a shared reference to
-    /// the value wrapped in `Some`. In contrast to [`as_ref`], this does not require
-    /// that the value has to be initialized.
-    ///
-    /// [`as_ref`]: #method.as_ref
-    ///
-    /// # Safety
-    ///
-    /// When calling this method, you have to ensure that *either* the pointer is null *or*
-    /// the pointer is [convertible to a reference](crate::ptr#pointer-to-reference-conversion).
-    ///
-    /// # Panics during const evaluation
-    ///
-    /// This method will panic during const evaluation if the pointer cannot be
-    /// determined to be null or not. See [`is_null`] for more information.
+    #[doc = include_str!("./docs/as_uninit_ref.md")]
     ///
     /// [`is_null`]: #method.is_null
+    /// [`as_ref`]: #method.as_ref
     ///
     /// # Examples
     ///

library/core/src/ptr/docs/INFO.md

@@ -0,0 +1,21 @@
+This directory holds method documentation that otherwise
+would be duplicated across mutable and immutable pointers.
+
+Note that most of the docs here are not the complete docs
+for their corresponding method. This is for a few reasons:
+
+1. Examples need to be different for mutable/immutable
+   pointers, in order to actually call the correct method.
+2. Link reference definitions are frequently different
+   between mutable/immutable pointers, in order to link to
+   the correct method.
+   For example, `<*const T>::as_ref` links to
+   `<*const T>::is_null`, while `<*mut T>::as_ref` links to
+   `<*mut T>::is_null`.
+3. Many methods on mutable pointers link to an alternate
+   version that returns a mutable reference instead of
+   a shared reference.
+
+Always review the rendered docs manually when making
+changes to these files to make sure you're not accidentally
+splitting up a section.