Rollup of 7 pull requests

Cargo.lock

@@ -3815,6 +3815,7 @@ dependencies = [
  "rustc_query_system",
  "rustc_resolve",
  "rustc_session",
+ "rustc_smir",
  "rustc_span",
  "rustc_symbol_mangling",
  "rustc_target",

compiler/rustc_ast_lowering/src/expr.rs

@@ -42,8 +42,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     }
                     // Merge attributes into the inner expression.
                     if !e.attrs.is_empty() {
-                        let old_attrs =
-                            self.attrs.get(&ex.hir_id.local_id).map(|la| *la).unwrap_or(&[]);
+                        let old_attrs = self.attrs.get(&ex.hir_id.local_id).copied().unwrap_or(&[]);
                         self.attrs.insert(
                             ex.hir_id.local_id,
                             &*self.arena.alloc_from_iter(

compiler/rustc_ast_lowering/src/lib.rs

@@ -499,7 +499,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     /// Given the id of some node in the AST, finds the `LocalDefId` associated with it by the name
     /// resolver (if any).
     fn orig_opt_local_def_id(&self, node: NodeId) -> Option<LocalDefId> {
-        self.resolver.node_id_to_def_id.get(&node).map(|local_def_id| *local_def_id)
+        self.resolver.node_id_to_def_id.get(&node).copied()
     }
 
     /// Given the id of some node in the AST, finds the `LocalDefId` associated with it by the name
@@ -542,7 +542,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.generics_def_id_map
             .iter()
             .rev()
-            .find_map(|map| map.get(&local_def_id).map(|local_def_id| *local_def_id))
+            .find_map(|map| map.get(&local_def_id).copied())
             .unwrap_or(local_def_id)
     }
 

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -990,11 +990,7 @@ unsafe fn embed_bitcode(
     // reason (see issue #90326 for historical background).
     let is_aix = target_is_aix(cgcx);
     let is_apple = target_is_apple(cgcx);
-    if is_apple
-        || is_aix
-        || cgcx.opts.target_triple.triple().starts_with("wasm")
-        || cgcx.opts.target_triple.triple().starts_with("asmjs")
-    {
+    if is_apple || is_aix || cgcx.opts.target_triple.triple().starts_with("wasm") {
         // We don't need custom section flags, create LLVM globals.
         let llconst = common::bytes_in_context(llcx, bitcode);
         let llglobal = llvm::LLVMAddGlobal(

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -2243,9 +2243,9 @@ fn linker_with_args<'a>(
     // ------------ Late order-dependent options ------------
 
     // Doesn't really make sense.
-    // FIXME: In practice built-in target specs use this for arbitrary order-independent options,
-    // introduce a target spec option for order-independent linker options, migrate built-in specs
-    // to it and remove the option.
+    // FIXME: In practice built-in target specs use this for arbitrary order-independent options.
+    // Introduce a target spec option for order-independent linker options, migrate built-in specs
+    // to it and remove the option. Currently the last holdout is wasm32-unknown-emscripten.
     add_post_link_args(cmd, sess, flavor);
 
     Ok(cmd.take_cmd())

compiler/rustc_driver_impl/Cargo.toml

@@ -43,6 +43,7 @@ rustc_privacy = { path = "../rustc_privacy" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_resolve = { path = "../rustc_resolve" }
 rustc_session = { path = "../rustc_session" }
+rustc_smir ={ path = "../rustc_smir" }
 rustc_span = { path = "../rustc_span" }
 rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_target = { path = "../rustc_target" }

compiler/rustc_driver_impl/src/pretty.rs

@@ -9,6 +9,7 @@ use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::config::{OutFileName, PpHirMode, PpMode, PpSourceMode};
 use rustc_session::Session;
+use rustc_smir::rustc_internal::pretty::write_smir_pretty;
 use rustc_span::symbol::Ident;
 use rustc_span::FileName;
 
@@ -325,6 +326,11 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             write_mir_graphviz(ex.tcx(), None, &mut out).unwrap();
             String::from_utf8(out).unwrap()
         }
+        StableMir => {
+            let mut out = Vec::new();
+            write_smir_pretty(ex.tcx(), &mut out).unwrap();
+            String::from_utf8(out).unwrap()
+        }
         ThirTree => {
             let tcx = ex.tcx();
             let mut out = String::new();

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

@@ -860,7 +860,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                         self.suggest_boxing_for_return_impl_trait(
                             err,
                             ret_sp,
-                            prior_arms.iter().chain(std::iter::once(&arm_span)).map(|s| *s),
+                            prior_arms.iter().chain(std::iter::once(&arm_span)).copied(),
                         );
                     }
                 }

compiler/rustc_lint/src/context.rs

@@ -703,7 +703,7 @@ pub trait LintContext {
                     db.note("see the asm section of Rust By Example <https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html#labels> for more information");
                 },
                 BuiltinLintDiagnostics::UnexpectedCfgName((name, name_span), value) => {
-                    let possibilities: Vec<Symbol> = sess.parse_sess.check_config.expecteds.keys().map(|s| *s).collect();
+                    let possibilities: Vec<Symbol> = sess.parse_sess.check_config.expecteds.keys().copied().collect();
 
                     // Suggest the most probable if we found one
                     if let Some(best_match) = find_best_match_for_name(&possibilities, name, None) {

compiler/rustc_middle/src/mir/pretty.rs

@@ -1337,7 +1337,7 @@ pub fn write_allocations<'tcx>(
     fn alloc_ids_from_alloc(
         alloc: ConstAllocation<'_>,
     ) -> impl DoubleEndedIterator<Item = AllocId> + '_ {
-        alloc.inner().provenance().ptrs().values().map(|id| *id)
+        alloc.inner().provenance().ptrs().values().copied()
     }
 
     fn alloc_ids_from_const_val(val: ConstValue<'_>) -> impl Iterator<Item = AllocId> + '_ {

compiler/rustc_resolve/src/diagnostics.rs

@@ -2028,7 +2028,19 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     },
                 )
             });
-            (format!("use of undeclared crate or module `{ident}`"), suggestion)
+            if let Ok(binding) = self.early_resolve_ident_in_lexical_scope(
+                ident,
+                ScopeSet::All(ValueNS),
+                parent_scope,
+                None,
+                false,
+                ignore_binding,
+            ) {
+                let descr = binding.res().descr();
+                (format!("{descr} `{ident}` is not a crate or module"), suggestion)
+            } else {
+                (format!("use of undeclared crate or module `{ident}`"), suggestion)
+            }
         }
     }
 

compiler/rustc_session/src/config.rs

@@ -2926,12 +2926,13 @@ fn parse_pretty(handler: &EarlyErrorHandler, unstable_opts: &UnstableOptions) ->
         "thir-tree" => ThirTree,
         "thir-flat" => ThirFlat,
         "mir" => Mir,
+        "stable-mir" => StableMir,
         "mir-cfg" => MirCFG,
         name => handler.early_error(format!(
             "argument to `unpretty` must be one of `normal`, `identified`, \
                             `expanded`, `expanded,identified`, `expanded,hygiene`, \
                             `ast-tree`, `ast-tree,expanded`, `hir`, `hir,identified`, \
-                            `hir,typed`, `hir-tree`, `thir-tree`, `thir-flat`, `mir` or \
+                            `hir,typed`, `hir-tree`, `thir-tree`, `thir-flat`, `mir`, `stable-mir`, or \
                             `mir-cfg`; got {name}"
         )),
     };
@@ -3106,6 +3107,8 @@ pub enum PpMode {
     Mir,
     /// `-Zunpretty=mir-cfg`
     MirCFG,
+    /// `-Zunpretty=stable-mir`
+    StableMir,
 }
 
 impl PpMode {
@@ -3122,21 +3125,22 @@ impl PpMode {
             | ThirTree
             | ThirFlat
             | Mir
-            | MirCFG => true,
+            | MirCFG
+            | StableMir => true,
         }
     }
     pub fn needs_hir(&self) -> bool {
         use PpMode::*;
         match *self {
             Source(_) | AstTree | AstTreeExpanded => false,
 
-            Hir(_) | HirTree | ThirTree | ThirFlat | Mir | MirCFG => true,
+            Hir(_) | HirTree | ThirTree | ThirFlat | Mir | MirCFG | StableMir => true,
         }
     }
 
     pub fn needs_analysis(&self) -> bool {
         use PpMode::*;
-        matches!(*self, Hir(PpHirMode::Typed) | Mir | MirCFG | ThirTree | ThirFlat)
+        matches!(*self, Hir(PpHirMode::Typed) | Mir | StableMir | MirCFG | ThirTree | ThirFlat)
     }
 }
 

compiler/rustc_smir/src/rustc_internal/mod.rs

@@ -21,6 +21,7 @@ use std::hash::Hash;
 use std::ops::Index;
 
 mod internal;
+pub mod pretty;
 
 pub fn stable<'tcx, S: Stable<'tcx>>(item: S) -> S::T {
     with_tables(|tables| item.stable(tables))

compiler/rustc_smir/src/rustc_internal/pretty.rs

@@ -0,0 +1,20 @@
+use std::io;
+
+use super::run;
+use rustc_middle::ty::TyCtxt;
+
+pub fn write_smir_pretty<'tcx, W: io::Write>(tcx: TyCtxt<'tcx>, w: &mut W) -> io::Result<()> {
+    writeln!(
+        w,
+        "// WARNING: This is highly experimental output it's intended for stable-mir developers only."
+    )?;
+    writeln!(
+        w,
+        "// If you find a bug or want to improve the output open a issue at https://github.com/rust-lang/project-stable-mir."
+    )?;
+    let _ = run(tcx, || {
+        let items = stable_mir::all_local_items();
+        let _ = items.iter().map(|item| -> io::Result<()> { item.dump(w) }).collect::<Vec<_>>();
+    });
+    Ok(())
+}

compiler/rustc_smir/src/rustc_smir/mod.rs

@@ -7,7 +7,7 @@
 //!
 //! For now, we are developing everything inside `rustc`, thus, we keep this module private.
 
-use crate::rustc_internal::{IndexMap, RustcInternal};
+use crate::rustc_internal::{internal, IndexMap, RustcInternal};
 use crate::rustc_smir::stable_mir::ty::{BoundRegion, Region};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
@@ -105,6 +105,10 @@ impl<'tcx> Context for TablesWrapper<'tcx> {
         tables.tcx.type_of(item.internal(&mut *tables)).instantiate_identity().stable(&mut *tables)
     }
 
+    fn const_literal(&self, cnst: &stable_mir::ty::Const) -> String {
+        internal(cnst).to_string()
+    }
+
     fn span_of_an_item(&self, def_id: stable_mir::DefId) -> Span {
         let mut tables = self.0.borrow_mut();
         tables.tcx.def_span(tables[def_id]).stable(&mut *tables)
@@ -404,6 +408,7 @@ impl<'tcx> Stable<'tcx> for mir::Body<'tcx> {
                 .map(|decl| stable_mir::mir::LocalDecl {
                     ty: decl.ty.stable(tables),
                     span: decl.source_info.span.stable(tables),
+                    mutability: decl.mutability.stable(tables),
                 })
                 .collect(),
             self.arg_count,

compiler/rustc_target/src/abi/call/mod.rs

@@ -836,7 +836,6 @@ impl<'a, Ty> FnAbi<'a, Ty> {
                     wasm::compute_c_abi_info(cx, self)
                 }
             }
-            "asmjs" => wasm::compute_c_abi_info(cx, self),
             "bpf" => bpf::compute_abi_info(self),
             arch => {
                 return Err(AdjustForForeignAbiError::Unsupported {

compiler/rustc_target/src/spec/mod.rs

@@ -1609,7 +1609,6 @@ supported_targets! {
     ("thumbv7a-pc-windows-msvc", thumbv7a_pc_windows_msvc),
     ("thumbv7a-uwp-windows-msvc", thumbv7a_uwp_windows_msvc),
 
-    ("asmjs-unknown-emscripten", asmjs_unknown_emscripten),
     ("wasm32-unknown-emscripten", wasm32_unknown_emscripten),
     ("wasm32-unknown-unknown", wasm32_unknown_unknown),
     ("wasm32-wasi", wasm32_wasi),
@@ -2244,10 +2243,6 @@ impl TargetOptions {
         add_link_args(&mut self.pre_link_args, flavor, args);
     }
 
-    fn add_post_link_args(&mut self, flavor: LinkerFlavor, args: &[&'static str]) {
-        add_link_args(&mut self.post_link_args, flavor, args);
-    }
-
     fn update_from_cli(&mut self) {
         self.linker_flavor = LinkerFlavor::from_cli_json(
             self.linker_flavor_json,

compiler/rustc_trait_selection/src/traits/coherence.rs

@@ -397,7 +397,11 @@ fn impl_intersection_has_negative_obligation(
 ) -> bool {
     debug!("negative_impl(impl1_def_id={:?}, impl2_def_id={:?})", impl1_def_id, impl2_def_id);
 
-    let ref infcx = tcx.infer_ctxt().intercrate(true).with_next_trait_solver(true).build();
+    // N.B. We don't need to use intercrate mode here because we're trying to prove
+    // the *existence* of a negative goal, not the non-existence of a positive goal.
+    // Without this, we over-eagerly register coherence ambiguity candidates when
+    // impl candidates do exist.
+    let ref infcx = tcx.infer_ctxt().with_next_trait_solver(true).build();
     let universe = infcx.universe();
 
     let impl1_header = fresh_impl_header(infcx, impl1_def_id);
@@ -542,14 +546,14 @@ fn try_prove_negated_where_clause<'tcx>(
     };
 
     // FIXME(with_negative_coherence): the infcx has region contraints from equating
-    // the impl headers as requirements. Given that the only region constraints we
-    // get are involving inference regions in the root, it shouldn't matter, but
-    // still sus.
+    // the impl headers as requirements.
     //
-    // We probably should just throw away the region obligations registered up until
-    // now, or ideally use them as assumptions when proving the region obligations
-    // that we get from proving the negative predicate below.
+    // We ideally should use these region constraints as assumptions when proving
+    // the region obligations that we get from proving the negative predicate below.
     let ref infcx = root_infcx.fork();
+    let _ = infcx.take_registered_region_obligations();
+    let _ = infcx.take_and_reset_region_constraints();
+
     let ocx = ObligationCtxt::new(infcx);
 
     ocx.register_obligation(Obligation::new(

compiler/rustc_ty_utils/src/assoc.rs

@@ -43,7 +43,7 @@ fn associated_item_def_ids(tcx: TyCtxt<'_>, def_id: LocalDefId) -> &[DefId] {
                                     trait_fn_def_id,
                                 )
                             })
-                            .map(|def_id| *def_id),
+                            .copied(),
                     ),
             )
         }
@@ -69,7 +69,7 @@ fn associated_item_def_ids(tcx: TyCtxt<'_>, def_id: LocalDefId) -> &[DefId] {
                                     impl_fn_def_id,
                                 )
                             })
-                            .map(|def_id| *def_id)
+                            .copied()
                     })),
             )
         }

compiler/stable_mir/src/lib.rs

@@ -19,9 +19,9 @@
 
 use crate::mir::mono::InstanceDef;
 use crate::mir::Body;
-use std::cell::Cell;
 use std::fmt;
 use std::fmt::Debug;
+use std::{cell::Cell, io};
 
 use self::ty::{
     GenericPredicates, Generics, ImplDef, ImplTrait, IndexedVal, LineInfo, Span, TraitDecl,
@@ -36,10 +36,12 @@ pub mod mir;
 pub mod ty;
 pub mod visitor;
 
+use crate::mir::pretty::function_name;
+use crate::mir::Mutability;
 use crate::ty::{AdtDef, AdtKind, ClosureDef, ClosureKind};
 pub use error::*;
 use mir::mono::Instance;
-use ty::{FnDef, GenericArgs};
+use ty::{Const, FnDef, GenericArgs};
 
 /// Use String for now but we should replace it.
 pub type Symbol = String;
@@ -137,6 +139,11 @@ impl CrateItem {
     pub fn ty(&self) -> Ty {
         with(|cx| cx.def_ty(self.0))
     }
+
+    pub fn dump<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
+        writeln!(w, "{}", function_name(*self))?;
+        self.body().dump(w)
+    }
 }
 
 /// Return the function where execution starts if the current
@@ -223,6 +230,9 @@ pub trait Context {
     /// Returns the type of given crate item.
     fn def_ty(&self, item: DefId) -> Ty;
 
+    /// Returns literal value of a const as a string.
+    fn const_literal(&self, cnst: &Const) -> String;
+
     /// `Span` of an item
     fn span_of_an_item(&self, def_id: DefId) -> Span;
 

compiler/stable_mir/src/mir.rs

@@ -1,5 +1,6 @@
 mod body;
 pub mod mono;
+pub mod pretty;
 pub mod visit;
 
 pub use body::*;