Rollup of 6 pull requests

compiler/rustc_ast/src/token.rs

@@ -881,11 +881,11 @@ impl Token {
     }
 
     pub fn is_qpath_start(&self) -> bool {
-        self == &Lt || self == &Shl
+        matches!(self.kind, Lt | Shl)
     }
 
     pub fn is_path_start(&self) -> bool {
-        self == &PathSep
+        self.kind == PathSep
             || self.is_qpath_start()
             || matches!(self.is_metavar_seq(), Some(MetaVarKind::Path))
             || self.is_path_segment_keyword()

compiler/rustc_attr_parsing/src/attributes/codegen_attrs.rs

@@ -6,6 +6,7 @@ use crate::session_diagnostics::{
     NakedFunctionIncompatibleAttribute, NullOnExport, NullOnObjcClass, NullOnObjcSelector,
     ObjcClassExpectedStringLiteral, ObjcSelectorExpectedStringLiteral,
 };
+use crate::target_checking::Policy::AllowSilent;
 
 pub(crate) struct OptimizeParser;
 
@@ -362,6 +363,8 @@ impl<S: Stage> NoArgsAttributeParser<S> for NoMangleParser {
         Allow(Target::Static),
         Allow(Target::Method(MethodKind::Inherent)),
         Allow(Target::Method(MethodKind::TraitImpl)),
+        AllowSilent(Target::Const), // Handled in the `InvalidNoMangleItems` pass
+        Error(Target::Closure),
     ]);
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::NoMangle;
 }

compiler/rustc_attr_parsing/src/target_checking.rs

@@ -31,7 +31,9 @@ impl AllowedTargets {
     pub(crate) fn is_allowed(&self, target: Target) -> AllowedResult {
         match self {
             AllowedTargets::AllowList(list) => {
-                if list.contains(&Policy::Allow(target)) {
+                if list.contains(&Policy::Allow(target))
+                    || list.contains(&Policy::AllowSilent(target))
+                {
                     AllowedResult::Allowed
                 } else if list.contains(&Policy::Warn(target)) {
                     AllowedResult::Warn
@@ -40,7 +42,9 @@ impl AllowedTargets {
                 }
             }
             AllowedTargets::AllowListWarnRest(list) => {
-                if list.contains(&Policy::Allow(target)) {
+                if list.contains(&Policy::Allow(target))
+                    || list.contains(&Policy::AllowSilent(target))
+                {
                     AllowedResult::Allowed
                 } else if list.contains(&Policy::Error(target)) {
                     AllowedResult::Error
@@ -61,17 +65,26 @@ impl AllowedTargets {
         .iter()
         .filter_map(|target| match target {
             Policy::Allow(target) => Some(*target),
+            Policy::AllowSilent(_) => None, // Not listed in possible targets
             Policy::Warn(_) => None,
             Policy::Error(_) => None,
         })
         .collect()
     }
 }
 
+/// This policy determines what diagnostics should be emitted based on the `Target` of the attribute.
 #[derive(Debug, Eq, PartialEq)]
 pub(crate) enum Policy {
+    /// A target that is allowed.
     Allow(Target),
+    /// A target that is allowed and not listed in the possible targets.
+    /// This is useful if the target is checked elsewhere.
+    AllowSilent(Target),
+    /// Emits a FCW on this target.
+    /// This is useful if the target was previously allowed but should not be.
     Warn(Target),
+    /// Emits an error on this target.
     Error(Target),
 }
 

compiler/rustc_builtin_macros/src/format.rs

@@ -69,35 +69,26 @@ struct MacroInput {
 /// Ok((fmtstr, parsed arguments))
 /// ```
 fn parse_args<'a>(ecx: &ExtCtxt<'a>, sp: Span, tts: TokenStream) -> PResult<'a, MacroInput> {
-    let mut args = FormatArguments::new();
-
     let mut p = ecx.new_parser_from_tts(tts);
 
-    if p.token == token::Eof {
-        return Err(ecx.dcx().create_err(errors::FormatRequiresString { span: sp }));
-    }
-
-    let first_token = &p.token;
-
-    let fmtstr = if let token::Literal(lit) = first_token.kind
-        && matches!(lit.kind, token::Str | token::StrRaw(_))
-    {
+    // parse the format string
+    let fmtstr = match p.token.kind {
+        token::Eof => return Err(ecx.dcx().create_err(errors::FormatRequiresString { span: sp })),
         // This allows us to properly handle cases when the first comma
         // after the format string is mistakenly replaced with any operator,
         // which cause the expression parser to eat too much tokens.
-        p.parse_literal_maybe_minus()?
-    } else {
+        token::Literal(token::Lit { kind: token::Str | token::StrRaw(_), .. }) => {
+            p.parse_literal_maybe_minus()?
+        }
         // Otherwise, we fall back to the expression parser.
-        p.parse_expr()?
+        _ => p.parse_expr()?,
     };
 
-    // Only allow implicit captures to be used when the argument is a direct literal
-    // instead of a macro expanding to one.
-    let is_direct_literal = matches!(fmtstr.kind, ExprKind::Lit(_));
-
+    // parse comma FormatArgument pairs
+    let mut args = FormatArguments::new();
     let mut first = true;
-
     while p.token != token::Eof {
+        // parse a comma, or else report an error
         if !p.eat(exp!(Comma)) {
             if first {
                 p.clear_expected_token_types();
@@ -120,9 +111,11 @@ fn parse_args<'a>(ecx: &ExtCtxt<'a>, sp: Span, tts: TokenStream) -> PResult<'a,
             }
         }
         first = false;
+        // accept a trailing comma
         if p.token == token::Eof {
             break;
-        } // accept trailing commas
+        }
+        // parse a FormatArgument
         match p.token.ident() {
             Some((ident, _)) if p.look_ahead(1, |t| *t == token::Eq) => {
                 p.bump();
@@ -156,6 +149,10 @@ fn parse_args<'a>(ecx: &ExtCtxt<'a>, sp: Span, tts: TokenStream) -> PResult<'a,
             }
         }
     }
+
+    // Only allow implicit captures for direct literals
+    let is_direct_literal = matches!(fmtstr.kind, ExprKind::Lit(_));
+
     Ok(MacroInput { fmtstr, args, is_direct_literal })
 }
 

compiler/rustc_codegen_ssa/messages.ftl

@@ -223,8 +223,6 @@ codegen_ssa_multiple_main_functions = entry symbol `main` declared multiple time
 
 codegen_ssa_no_field = no field `{$name}`
 
-codegen_ssa_no_mangle_nameless = `#[no_mangle]` cannot be used on {$definition} as it has no name
-
 codegen_ssa_no_module_named =
     no module named `{$user_path}` (mangled: {$cgu_name}). available modules: {$cgu_names}
 

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -19,7 +19,6 @@ use rustc_span::{Ident, Span, sym};
 use rustc_target::spec::SanitizerSet;
 
 use crate::errors;
-use crate::errors::NoMangleNameless;
 use crate::target_features::{
     check_target_feature_trait_unsafe, check_tied_features, from_target_feature_attr,
 };
@@ -182,14 +181,10 @@ fn process_builtin_attrs(
                     if tcx.opt_item_name(did.to_def_id()).is_some() {
                         codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
                     } else {
-                        tcx.dcx().emit_err(NoMangleNameless {
-                            span: *attr_span,
-                            definition: format!(
-                                "{} {}",
-                                tcx.def_descr_article(did.to_def_id()),
-                                tcx.def_descr(did.to_def_id())
-                            ),
-                        });
+                        tcx.dcx().span_delayed_bug(
+                            *attr_span,
+                            "no_mangle should be on a named function",
+                        );
                     }
                 }
                 AttributeKind::Optimize(optimize, _) => codegen_fn_attrs.optimize = *optimize,

compiler/rustc_codegen_ssa/src/errors.rs

@@ -1284,14 +1284,6 @@ impl<G: EmissionGuarantee> Diagnostic<'_, G> for TargetFeatureDisableOrEnable<'_
     }
 }
 
-#[derive(Diagnostic)]
-#[diag(codegen_ssa_no_mangle_nameless)]
-pub(crate) struct NoMangleNameless {
-    #[primary_span]
-    pub span: Span,
-    pub definition: String,
-}
-
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_feature_not_valid)]
 pub(crate) struct FeatureNotValid<'a> {

compiler/rustc_mir_transform/src/ctfe_limit.rs

@@ -28,12 +28,12 @@ impl<'tcx> crate::MirPass<'tcx> for CtfeLimit {
                 }
             })
             .collect();
+
+        let basic_blocks = body.basic_blocks.as_mut_preserves_cfg();
         for index in indices {
-            insert_counter(
-                body.basic_blocks_mut()
-                    .get_mut(index)
-                    .expect("basic_blocks index {index} should exist"),
-            );
+            let bbdata = &mut basic_blocks[index];
+            let source_info = bbdata.terminator().source_info;
+            bbdata.statements.push(Statement::new(source_info, StatementKind::ConstEvalCounter));
         }
     }
 
@@ -53,10 +53,3 @@ fn has_back_edge(
     // Check if any of the dominators of the node are also the node's successor.
     node_data.terminator().successors().any(|succ| doms.dominates(succ, node))
 }
-
-fn insert_counter(basic_block_data: &mut BasicBlockData<'_>) {
-    basic_block_data.statements.push(Statement::new(
-        basic_block_data.terminator().source_info,
-        StatementKind::ConstEvalCounter,
-    ));
-}

compiler/rustc_span/src/symbol.rs

@@ -981,10 +981,12 @@ symbols! {
         external_doc,
         f,
         f16,
+        f16_consts_mod,
         f16_epsilon,
         f16_nan,
         f16c_target_feature,
         f32,
+        f32_consts_mod,
         f32_epsilon,
         f32_legacy_const_digits,
         f32_legacy_const_epsilon,
@@ -1002,6 +1004,7 @@ symbols! {
         f32_legacy_const_radix,
         f32_nan,
         f64,
+        f64_consts_mod,
         f64_epsilon,
         f64_legacy_const_digits,
         f64_legacy_const_epsilon,
@@ -1019,6 +1022,7 @@ symbols! {
         f64_legacy_const_radix,
         f64_nan,
         f128,
+        f128_consts_mod,
         f128_epsilon,
         f128_nan,
         fabsf16,

library/core/src/num/f128.rs

@@ -18,6 +18,7 @@ use crate::{intrinsics, mem};
 
 /// Basic mathematical constants.
 #[unstable(feature = "f128", issue = "116909")]
+#[rustc_diagnostic_item = "f128_consts_mod"]
 pub mod consts {
     // FIXME: replace with mathematical constants from cmath.
 

library/core/src/num/f16.rs

@@ -20,6 +20,7 @@ use crate::{intrinsics, mem};
 
 /// Basic mathematical constants.
 #[unstable(feature = "f16", issue = "116909")]
+#[rustc_diagnostic_item = "f16_consts_mod"]
 pub mod consts {
     // FIXME: replace with mathematical constants from cmath.
 

library/core/src/num/f32.rs

@@ -277,6 +277,7 @@ pub const NEG_INFINITY: f32 = f32::NEG_INFINITY;
 
 /// Basic mathematical constants.
 #[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_diagnostic_item = "f32_consts_mod"]
 pub mod consts {
     // FIXME: replace with mathematical constants from cmath.
 

library/core/src/num/f64.rs

@@ -277,6 +277,7 @@ pub const NEG_INFINITY: f64 = f64::NEG_INFINITY;
 
 /// Basic mathematical constants.
 #[stable(feature = "rust1", since = "1.0.0")]
+#[rustc_diagnostic_item = "f64_consts_mod"]
 pub mod consts {
     // FIXME: replace with mathematical constants from cmath.
 

library/core/src/panicking.rs

@@ -36,7 +36,8 @@ use crate::panic::{Location, PanicInfo};
 compile_error!(
     "panic_immediate_abort is now a real panic strategy! \
     Enable it with `panic = \"immediate-abort\"` in Cargo.toml, \
-    or with the compiler flags `-Zunstable-options -Cpanic=immediate-abort`"
+    or with the compiler flags `-Zunstable-options -Cpanic=immediate-abort`. \
+    In both cases, you still need to build core, e.g. with `-Zbuild-std`"
 );
 
 // First we define the two main entry points that all panics go through.

library/std/src/error.rs

@@ -123,7 +123,7 @@ use crate::fmt::{self, Write};
 /// the `Debug` output means `Report` is an ideal starting place for formatting errors returned
 /// from `main`.
 ///
-/// ```should_panic
+/// ```
 /// #![feature(error_reporter)]
 /// use std::error::Report;
 /// # use std::error::Error;
@@ -154,10 +154,14 @@ use crate::fmt::{self, Write};
 /// #     Err(SuperError { source: SuperErrorSideKick })
 /// # }
 ///
-/// fn main() -> Result<(), Report<SuperError>> {
+/// fn run() -> Result<(), Report<SuperError>> {
 ///     get_super_error()?;
 ///     Ok(())
 /// }
+///
+/// fn main() {
+///     assert!(run().is_err());
+/// }
 /// ```
 ///
 /// This example produces the following output:
@@ -170,7 +174,7 @@ use crate::fmt::{self, Write};
 /// output format. If you want to make sure your `Report`s are pretty printed and include backtrace
 /// you will need to manually convert and enable those flags.
 ///
-/// ```should_panic
+/// ```
 /// #![feature(error_reporter)]
 /// use std::error::Report;
 /// # use std::error::Error;
@@ -201,12 +205,16 @@ use crate::fmt::{self, Write};
 /// #     Err(SuperError { source: SuperErrorSideKick })
 /// # }
 ///
-/// fn main() -> Result<(), Report<SuperError>> {
+/// fn run() -> Result<(), Report<SuperError>> {
 ///     get_super_error()
 ///         .map_err(Report::from)
 ///         .map_err(|r| r.pretty(true).show_backtrace(true))?;
 ///     Ok(())
 /// }
+///
+/// fn main() {
+///     assert!(run().is_err());
+/// }
 /// ```
 ///
 /// This example produces the following output: