Auto merge of #130179 - workingjubilee:rollup-l78cv44, r=workingjubilee

Rollup of 11 pull requests

Successful merges:

 - #128316 (Stabilize most of `io_error_more`)
 - #129473 (use  `download-ci-llvm=true` in the default compiler config)
 - #129529 (Add test to build crates used by r-a on stable)
 - #129981 (Remove `serialized_bitcode` from `LtoModuleCodegen`.)
 - #130094 (Inform the solver if evaluation is concurrent)
 - #130132 ([illumos] enable SIGSEGV handler to detect stack overflows)
 - #130146 (bootstrap `naked_asm!` for `compiler-builtins`)
 - #130149 (Helper function for formatting with `LifetimeSuggestionPosition`)
 - #130152 (adapt a test for llvm 20)
 - #130162 (bump download-ci-llvm-stamp)
 - #130164 (move some const fn out of the const_ptr_as_ref feature)

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

Author: bors

compiler/rustc_builtin_macros/src/asm.rs

@@ -812,6 +812,44 @@ pub(super) fn expand_asm<'cx>(
     })
 }
 
+pub(super) fn expand_naked_asm<'cx>(
+    ecx: &'cx mut ExtCtxt<'_>,
+    sp: Span,
+    tts: TokenStream,
+) -> MacroExpanderResult<'cx> {
+    ExpandResult::Ready(match parse_args(ecx, sp, tts, false) {
+        Ok(args) => {
+            let ExpandResult::Ready(mac) = expand_preparsed_asm(ecx, args) else {
+                return ExpandResult::Retry(());
+            };
+            let expr = match mac {
+                Ok(mut inline_asm) => {
+                    // for future compatibility, we always set the NORETURN option.
+                    //
+                    // When we turn `asm!` into `naked_asm!` with this implementation, we can drop
+                    // the `options(noreturn)`, which makes the upgrade smooth when `naked_asm!`
+                    // starts disallowing the `noreturn` option in the future
+                    inline_asm.options |= ast::InlineAsmOptions::NORETURN;
+
+                    P(ast::Expr {
+                        id: ast::DUMMY_NODE_ID,
+                        kind: ast::ExprKind::InlineAsm(P(inline_asm)),
+                        span: sp,
+                        attrs: ast::AttrVec::new(),
+                        tokens: None,
+                    })
+                }
+                Err(guar) => DummyResult::raw_expr(sp, Some(guar)),
+            };
+            MacEager::expr(expr)
+        }
+        Err(err) => {
+            let guar = err.emit();
+            DummyResult::any(sp, guar)
+        }
+    })
+}
+
 pub(super) fn expand_global_asm<'cx>(
     ecx: &'cx mut ExtCtxt<'_>,
     sp: Span,

compiler/rustc_builtin_macros/src/lib.rs

@@ -94,6 +94,7 @@ pub fn register_builtin_macros(resolver: &mut dyn ResolverExpand) {
         line: source_util::expand_line,
         log_syntax: log_syntax::expand_log_syntax,
         module_path: source_util::expand_mod,
+        naked_asm: asm::expand_naked_asm,
         option_env: env::expand_option_env,
         pattern_type: pattern_type::expand,
         std_panic: edition_panic::expand_panic,

compiler/rustc_codegen_gcc/src/back/lto.rs

@@ -272,7 +272,6 @@ fn fat_lto(
             }*/
         }
     };
-    let mut serialized_bitcode = Vec::new();
     {
         info!("using {:?} as a base module", module.name);
 
@@ -317,7 +316,6 @@ fn fat_lto(
                     unimplemented!("from uncompressed file")
                 }
             }
-            serialized_bitcode.push(bc_decoded);
         }
         save_temp_bitcode(cgcx, &module, "lto.input");
 
@@ -337,7 +335,7 @@ fn fat_lto(
     // of now.
     module.module_llvm.temp_dir = Some(tmp_path);
 
-    Ok(LtoModuleCodegen::Fat { module, _serialized_bitcode: serialized_bitcode })
+    Ok(LtoModuleCodegen::Fat(module))
 }
 
 pub struct ModuleBuffer(PathBuf);

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -314,7 +314,6 @@ fn fat_lto(
             }
         }
     };
-    let mut serialized_bitcode = Vec::new();
     {
         let (llcx, llmod) = {
             let llvm = &module.module_llvm;
@@ -342,9 +341,7 @@ fn fat_lto(
         serialized_modules.sort_by(|module1, module2| module1.1.cmp(&module2.1));
 
         // For all serialized bitcode files we parse them and link them in as we did
-        // above, this is all mostly handled in C++. Like above, though, we don't
-        // know much about the memory management here so we err on the side of being
-        // save and persist everything with the original module.
+        // above, this is all mostly handled in C++.
         let mut linker = Linker::new(llmod);
         for (bc_decoded, name) in serialized_modules {
             let _timer = cgcx
@@ -355,7 +352,6 @@ fn fat_lto(
             info!("linking {:?}", name);
             let data = bc_decoded.data();
             linker.add(data).map_err(|()| write::llvm_err(dcx, LlvmError::LoadBitcode { name }))?;
-            serialized_bitcode.push(bc_decoded);
         }
         drop(linker);
         save_temp_bitcode(cgcx, &module, "lto.input");
@@ -372,7 +368,7 @@ fn fat_lto(
         }
     }
 
-    Ok(LtoModuleCodegen::Fat { module, _serialized_bitcode: serialized_bitcode })
+    Ok(LtoModuleCodegen::Fat(module))
 }
 
 pub(crate) struct Linker<'a>(&'a mut llvm::Linker<'a>);

compiler/rustc_codegen_ssa/src/back/lto.rs

@@ -41,18 +41,14 @@ pub struct ThinShared<B: WriteBackendMethods> {
 }
 
 pub enum LtoModuleCodegen<B: WriteBackendMethods> {
-    Fat {
-        module: ModuleCodegen<B::Module>,
-        _serialized_bitcode: Vec<SerializedModule<B::ModuleBuffer>>,
-    },
-
+    Fat(ModuleCodegen<B::Module>),
     Thin(ThinModule<B>),
 }
 
 impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
     pub fn name(&self) -> &str {
         match *self {
-            LtoModuleCodegen::Fat { .. } => "everything",
+            LtoModuleCodegen::Fat(_) => "everything",
             LtoModuleCodegen::Thin(ref m) => m.name(),
         }
     }
@@ -68,7 +64,7 @@ impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
         cgcx: &CodegenContext<B>,
     ) -> Result<ModuleCodegen<B::Module>, FatalError> {
         match self {
-            LtoModuleCodegen::Fat { mut module, .. } => {
+            LtoModuleCodegen::Fat(mut module) => {
                 B::optimize_fat(cgcx, &mut module)?;
                 Ok(module)
             }
@@ -81,7 +77,7 @@ impl<B: WriteBackendMethods> LtoModuleCodegen<B> {
     pub fn cost(&self) -> u64 {
         match *self {
             // Only one module with fat LTO, so the cost doesn't matter.
-            LtoModuleCodegen::Fat { .. } => 0,
+            LtoModuleCodegen::Fat(_) => 0,
             LtoModuleCodegen::Thin(ref m) => m.cost(),
         }
     }

compiler/rustc_hir/src/hir.rs

@@ -168,6 +168,19 @@ impl Lifetime {
             (LifetimeSuggestionPosition::Normal, self.ident.span)
         }
     }
+
+    pub fn suggestion(&self, new_lifetime: &str) -> (Span, String) {
+        debug_assert!(new_lifetime.starts_with('\''));
+        let (pos, span) = self.suggestion_position();
+        let code = match pos {
+            LifetimeSuggestionPosition::Normal => format!("{new_lifetime}"),
+            LifetimeSuggestionPosition::Ampersand => format!("{new_lifetime} "),
+            LifetimeSuggestionPosition::ElidedPath => format!("<{new_lifetime}>"),
+            LifetimeSuggestionPosition::ElidedPathArgument => format!("{new_lifetime}, "),
+            LifetimeSuggestionPosition::ObjectDefault => format!("+ {new_lifetime}"),
+        };
+        (span, code)
+    }
 }
 
 /// A `Path` is essentially Rust's notion of a name; for instance,

compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs

@@ -1191,23 +1191,7 @@ impl<'a, 'tcx> BoundVarContext<'a, 'tcx> {
                                     (generics.span, "<'a>".to_owned())
                                 };
 
-                            let lifetime_sugg = match lifetime_ref.suggestion_position() {
-                                (hir::LifetimeSuggestionPosition::Normal, span) => {
-                                    (span, "'a".to_owned())
-                                }
-                                (hir::LifetimeSuggestionPosition::Ampersand, span) => {
-                                    (span, "'a ".to_owned())
-                                }
-                                (hir::LifetimeSuggestionPosition::ElidedPath, span) => {
-                                    (span, "<'a>".to_owned())
-                                }
-                                (hir::LifetimeSuggestionPosition::ElidedPathArgument, span) => {
-                                    (span, "'a, ".to_owned())
-                                }
-                                (hir::LifetimeSuggestionPosition::ObjectDefault, span) => {
-                                    (span, "+ 'a".to_owned())
-                                }
-                            };
+                            let lifetime_sugg = lifetime_ref.suggestion("'a");
                             let suggestions = vec![lifetime_sugg, new_param_sugg];
 
                             diag.span_label(

compiler/rustc_middle/src/ty/context.rs

@@ -181,6 +181,10 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
         }
     }
 
+    fn evaluation_is_concurrent(&self) -> bool {
+        self.sess.threads() > 1
+    }
+
     fn expand_abstract_consts<T: TypeFoldable<TyCtxt<'tcx>>>(self, t: T) -> T {
         self.expand_abstract_consts(t)
     }

compiler/rustc_span/src/symbol.rs

@@ -1255,6 +1255,7 @@ symbols! {
         mut_preserve_binding_mode_2024,
         mut_ref,
         naked,
+        naked_asm,
         naked_functions,
         name,
         names,

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

@@ -852,18 +852,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
         impl<'hir, 'tcx> hir::intravisit::Visitor<'hir> for LifetimeReplaceVisitor<'tcx, '_> {
             fn visit_lifetime(&mut self, lt: &'hir hir::Lifetime) {
                 if lt.res == self.needle {
-                    let (pos, span) = lt.suggestion_position();
-                    let new_lt = &self.new_lt;
-                    let sugg = match pos {
-                        hir::LifetimeSuggestionPosition::Normal => format!("{new_lt}"),
-                        hir::LifetimeSuggestionPosition::Ampersand => format!("{new_lt} "),
-                        hir::LifetimeSuggestionPosition::ElidedPath => format!("<{new_lt}>"),
-                        hir::LifetimeSuggestionPosition::ElidedPathArgument => {
-                            format!("{new_lt}, ")
-                        }
-                        hir::LifetimeSuggestionPosition::ObjectDefault => format!("+ {new_lt}"),
-                    };
-                    self.add_lt_suggs.push((span, sugg));
+                    self.add_lt_suggs.push(lt.suggestion(self.new_lt));
                 }
             }
 

compiler/rustc_type_ir/src/elaborate.rs

@@ -237,7 +237,7 @@ pub fn supertrait_def_ids<I: Interner>(
     cx: I,
     trait_def_id: I::DefId,
 ) -> impl Iterator<Item = I::DefId> {
-    let mut set: HashSet<I::DefId> = HashSet::default();
+    let mut set = HashSet::default();
     let mut stack = vec![trait_def_id];
 
     set.insert(trait_def_id);

compiler/rustc_type_ir/src/interner.rs

@@ -137,6 +137,8 @@ pub trait Interner:
         f: impl FnOnce(&mut search_graph::GlobalCache<Self>) -> R,
     ) -> R;
 
+    fn evaluation_is_concurrent(&self) -> bool;
+
     fn expand_abstract_consts<T: TypeFoldable<Self>>(self, t: T) -> T;
 
     type GenericsOf: GenericsOf<Self>;
@@ -404,4 +406,7 @@ impl<I: Interner> search_graph::Cx for I {
     ) -> R {
         I::with_global_cache(self, mode, f)
     }
+    fn evaluation_is_concurrent(&self) -> bool {
+        self.evaluation_is_concurrent()
+    }
 }

compiler/rustc_type_ir/src/search_graph/global_cache.rs

@@ -44,22 +44,28 @@ impl<X: Cx> GlobalCache<X> {
         cx: X,
         input: X::Input,
 
-        result: X::Result,
+        origin_result: X::Result,
         dep_node: X::DepNodeIndex,
 
         additional_depth: usize,
         encountered_overflow: bool,
         nested_goals: NestedGoals<X>,
     ) {
-        let result = cx.mk_tracked(result, dep_node);
+        let result = cx.mk_tracked(origin_result, dep_node);
         let entry = self.map.entry(input).or_default();
         if encountered_overflow {
             let with_overflow = WithOverflow { nested_goals, result };
             let prev = entry.with_overflow.insert(additional_depth, with_overflow);
-            assert!(prev.is_none());
+            if let Some(prev) = &prev {
+                assert!(cx.evaluation_is_concurrent());
+                assert_eq!(cx.get_tracked(&prev.result), origin_result);
+            }
         } else {
             let prev = entry.success.replace(Success { additional_depth, nested_goals, result });
-            assert!(prev.is_none());
+            if let Some(prev) = &prev {
+                assert!(cx.evaluation_is_concurrent());
+                assert_eq!(cx.get_tracked(&prev.result), origin_result);
+            }
         }
     }
 

compiler/rustc_type_ir/src/search_graph/mod.rs

@@ -53,6 +53,8 @@ pub trait Cx: Copy {
         mode: SolverMode,
         f: impl FnOnce(&mut GlobalCache<Self>) -> R,
     ) -> R;
+
+    fn evaluation_is_concurrent(&self) -> bool;
 }
 
 pub trait Delegate {

config.example.toml

@@ -42,6 +42,9 @@
 # Unless you're developing for a target where Rust CI doesn't build a compiler
 # toolchain or changing LLVM locally, you probably want to leave this enabled.
 #
+# Set this to `true` to download if CI llvm available otherwise it builds
+# from `src/llvm-project`.
+#
 # Set this to `"if-unchanged"` to download only if the llvm-project has not
 # been modified. You can also use this if you are unsure whether you're on a
 # tier 1 target. All tier 1 targets are currently supported.
@@ -236,7 +239,7 @@
 # Instead of downloading the src/stage0 version of cargo-clippy specified,
 # use this cargo-clippy binary instead as the stage0 snapshot cargo-clippy.
 #
-# Note that this option should be used with the same toolchain as the `rustc` option above. 
+# Note that this option should be used with the same toolchain as the `rustc` option above.
 # Otherwise, clippy is likely to fail due to a toolchain conflict.
 #cargo-clippy = "/path/to/cargo-clippy"
 

library/core/src/arch.rs

@@ -17,6 +17,20 @@ pub macro asm("assembly template", $(operands,)* $(options($(option),*))?) {
     /* compiler built-in */
 }
 
+/// Inline assembly used in combination with `#[naked]` functions.
+///
+/// Refer to [Rust By Example] for a usage guide and the [reference] for
+/// detailed information about the syntax and available options.
+///
+/// [Rust By Example]: https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html
+/// [reference]: https://doc.rust-lang.org/nightly/reference/inline-assembly.html
+#[unstable(feature = "naked_functions", issue = "90957")]
+#[rustc_builtin_macro]
+#[cfg(not(bootstrap))]
+pub macro naked_asm("assembly template", $(operands,)* $(options($(option),*))?) {
+    /* compiler built-in */
+}
+
 /// Module-level inline assembly.
 ///
 /// Refer to [Rust By Example] for a usage guide and the [reference] for

library/core/src/ptr/const_ptr.rs

@@ -270,7 +270,7 @@ impl<T: ?Sized> *const T {
     /// }
     /// ```
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
-    #[rustc_const_unstable(feature = "const_ptr_as_ref", issue = "91822")]
+    #[rustc_const_unstable(feature = "const_ptr_is_null", issue = "74939")]
     #[inline]
     pub const unsafe fn as_ref<'a>(self) -> Option<&'a T> {
         // SAFETY: the caller must guarantee that `self` is valid
@@ -302,7 +302,7 @@ impl<T: ?Sized> *const T {
     /// ```
     // FIXME: mention it in the docs for `as_ref` and `as_uninit_ref` once stabilized.
     #[unstable(feature = "ptr_as_ref_unchecked", issue = "122034")]
-    #[rustc_const_unstable(feature = "const_ptr_as_ref", issue = "91822")]
+    #[rustc_const_unstable(feature = "ptr_as_ref_unchecked", issue = "122034")]
     #[inline]
     #[must_use]
     pub const unsafe fn as_ref_unchecked<'a>(self) -> &'a T {
@@ -336,7 +336,7 @@ impl<T: ?Sized> *const T {
     /// ```
     #[inline]
     #[unstable(feature = "ptr_as_uninit", issue = "75402")]
-    #[rustc_const_unstable(feature = "const_ptr_as_ref", issue = "91822")]
+    #[rustc_const_unstable(feature = "ptr_as_uninit", issue = "75402")]
     pub const unsafe fn as_uninit_ref<'a>(self) -> Option<&'a MaybeUninit<T>>
     where
         T: Sized,
@@ -1664,7 +1664,7 @@ impl<T> *const [T] {
     /// [allocated object]: crate::ptr#allocated-object
     #[inline]
     #[unstable(feature = "ptr_as_uninit", issue = "75402")]
-    #[rustc_const_unstable(feature = "const_ptr_as_ref", issue = "91822")]
+    #[rustc_const_unstable(feature = "ptr_as_uninit", issue = "75402")]
     pub const unsafe fn as_uninit_slice<'a>(self) -> Option<&'a [MaybeUninit<T>]> {
         if self.is_null() {
             None