Rollup of 13 pull requests

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -1416,10 +1416,11 @@ fn generator_layout_and_saved_local_names(
 
     let state_arg = mir::Local::new(1);
     for var in &body.var_debug_info {
-        if var.place.local != state_arg {
+        let place = if let mir::VarDebugInfoContents::Place(p) = var.value { p } else { continue };
+        if place.local != state_arg {
             continue;
         }
-        match var.place.projection[..] {
+        match place.projection[..] {
             [
                 // Deref of the `Pin<&mut Self>` state argument.
                 mir::ProjectionElem::Field(..),

compiler/rustc_codegen_ssa/src/mir/constant.rs

@@ -11,7 +11,7 @@ use super::FunctionCx;
 
 impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
     pub fn eval_mir_constant_to_operand(
-        &mut self,
+        &self,
         bx: &mut Bx,
         constant: &mir::Constant<'tcx>,
     ) -> Result<OperandRef<'tcx, Bx::Value>, ErrorHandled> {
@@ -21,7 +21,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
     }
 
     pub fn eval_mir_constant(
-        &mut self,
+        &self,
         constant: &mir::Constant<'tcx>,
     ) -> Result<ConstValue<'tcx>, ErrorHandled> {
         match self.monomorphize(&constant.literal).val {

compiler/rustc_codegen_ssa/src/mir/debuginfo.rs

@@ -9,7 +9,7 @@ use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{BytePos, Span};
 use rustc_target::abi::{LayoutOf, Size};
 
-use super::operand::OperandValue;
+use super::operand::{OperandRef, OperandValue};
 use super::place::PlaceRef;
 use super::{FunctionCx, LocalRef};
 
@@ -111,6 +111,24 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         }
     }
 
+    fn spill_operand_to_stack(
+        operand: &OperandRef<'tcx, Bx::Value>,
+        name: Option<String>,
+        bx: &mut Bx,
+    ) -> PlaceRef<'tcx, Bx::Value> {
+        // "Spill" the value onto the stack, for debuginfo,
+        // without forcing non-debuginfo uses of the local
+        // to also load from the stack every single time.
+        // FIXME(#68817) use `llvm.dbg.value` instead,
+        // at least for the cases which LLVM handles correctly.
+        let spill_slot = PlaceRef::alloca(bx, operand.layout);
+        if let Some(name) = name {
+            bx.set_var_name(spill_slot.llval, &(name + ".dbg.spill"));
+        }
+        operand.val.store(bx, spill_slot);
+        spill_slot
+    }
+
     /// Apply debuginfo and/or name, after creating the `alloca` for a local,
     /// or initializing the local with an operand (whichever applies).
     pub fn debug_introduce_local(&self, bx: &mut Bx, local: mir::Local) {
@@ -225,17 +243,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     return;
                 }
 
-                // "Spill" the value onto the stack, for debuginfo,
-                // without forcing non-debuginfo uses of the local
-                // to also load from the stack every single time.
-                // FIXME(#68817) use `llvm.dbg.value` instead,
-                // at least for the cases which LLVM handles correctly.
-                let spill_slot = PlaceRef::alloca(bx, operand.layout);
-                if let Some(name) = name {
-                    bx.set_var_name(spill_slot.llval, &(name + ".dbg.spill"));
-                }
-                operand.val.store(bx, spill_slot);
-                spill_slot
+                Self::spill_operand_to_stack(operand, name, bx)
             }
 
             LocalRef::Place(place) => *place,
@@ -310,6 +318,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
     /// Partition all `VarDebugInfo` in `self.mir`, by their base `Local`.
     pub fn compute_per_local_var_debug_info(
         &self,
+        bx: &mut Bx,
     ) -> Option<IndexVec<mir::Local, Vec<PerLocalVarDebugInfo<'tcx, Bx::DIVariable>>>> {
         let full_debug_info = self.cx.sess().opts.debuginfo == DebugInfo::Full;
 
@@ -324,22 +333,30 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             } else {
                 (None, var.source_info.span)
             };
+            let (var_ty, var_kind) = match var.value {
+                mir::VarDebugInfoContents::Place(place) => {
+                    let var_ty = self.monomorphized_place_ty(place.as_ref());
+                    let var_kind = if self.mir.local_kind(place.local) == mir::LocalKind::Arg
+                        && place.projection.is_empty()
+                        && var.source_info.scope == mir::OUTERMOST_SOURCE_SCOPE
+                    {
+                        let arg_index = place.local.index() - 1;
+
+                        // FIXME(eddyb) shouldn't `ArgumentVariable` indices be
+                        // offset in closures to account for the hidden environment?
+                        // Also, is this `+ 1` needed at all?
+                        VariableKind::ArgumentVariable(arg_index + 1)
+                    } else {
+                        VariableKind::LocalVariable
+                    };
+                    (var_ty, var_kind)
+                }
+                mir::VarDebugInfoContents::Const(c) => {
+                    let ty = self.monomorphize(&c.literal.ty);
+                    (ty, VariableKind::LocalVariable)
+                }
+            };
             let dbg_var = scope.map(|scope| {
-                let place = var.place;
-                let var_ty = self.monomorphized_place_ty(place.as_ref());
-                let var_kind = if self.mir.local_kind(place.local) == mir::LocalKind::Arg
-                    && place.projection.is_empty()
-                    && var.source_info.scope == mir::OUTERMOST_SOURCE_SCOPE
-                {
-                    let arg_index = place.local.index() - 1;
-
-                    // FIXME(eddyb) shouldn't `ArgumentVariable` indices be
-                    // offset in closures to account for the hidden environment?
-                    // Also, is this `+ 1` needed at all?
-                    VariableKind::ArgumentVariable(arg_index + 1)
-                } else {
-                    VariableKind::LocalVariable
-                };
                 self.cx.create_dbg_var(
                     self.debug_context.as_ref().unwrap(),
                     var.name,
@@ -350,12 +367,29 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 )
             });
 
-            per_local[var.place.local].push(PerLocalVarDebugInfo {
-                name: var.name,
-                source_info: var.source_info,
-                dbg_var,
-                projection: var.place.projection,
-            });
+            match var.value {
+                mir::VarDebugInfoContents::Place(place) => {
+                    per_local[place.local].push(PerLocalVarDebugInfo {
+                        name: var.name,
+                        source_info: var.source_info,
+                        dbg_var,
+                        projection: place.projection,
+                    });
+                }
+                mir::VarDebugInfoContents::Const(c) => {
+                    if let (Some(scope), Some(dbg_var)) = (scope, dbg_var) {
+                        if let Ok(operand) = self.eval_mir_constant_to_operand(bx, &c) {
+                            let base = Self::spill_operand_to_stack(
+                                &operand,
+                                Some(var.name.to_string()),
+                                bx,
+                            );
+
+                            bx.dbg_var_addr(dbg_var, scope, base.llval, Size::ZERO, &[], span);
+                        }
+                    }
+                }
+            }
         }
         Some(per_local)
     }

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -190,7 +190,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         caller_location: None,
     };
 
-    fx.per_local_var_debug_info = fx.compute_per_local_var_debug_info();
+    fx.per_local_var_debug_info = fx.compute_per_local_var_debug_info(&mut bx);
 
     for const_ in &mir.required_consts {
         if let Err(err) = fx.eval_mir_constant(const_) {

compiler/rustc_driver/src/lib.rs

@@ -1258,9 +1258,9 @@ pub fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
     // If backtraces are enabled, also print the query stack
     let backtrace = env::var_os("RUST_BACKTRACE").map(|x| &x != "0").unwrap_or(false);
 
-    if backtrace {
-        TyCtxt::try_print_query_stack(&handler);
-    }
+    let num_frames = if backtrace { None } else { Some(2) };
+
+    TyCtxt::try_print_query_stack(&handler, num_frames);
 
     #[cfg(windows)]
     unsafe {

compiler/rustc_error_codes/src/error_codes/E0007.md

@@ -1,3 +1,5 @@
+#### Note: this error code is no longer emitted by the compiler.
+
 This error indicates that the bindings in a match arm would require a value to
 be moved into more than one location, thus violating unique ownership. Code
 like the following is invalid as it requires the entire `Option<String>` to be
@@ -6,11 +8,13 @@ inner `String` to be moved into a variable called `s`.
 
 Erroneous code example:
 
-```compile_fail,E0007
+```compile_fail,E0382
+#![feature(bindings_after_at)]
+
 let x = Some("s".to_string());
 
 match x {
-    op_string @ Some(s) => {}, // error: cannot bind by-move with sub-bindings
+    op_string @ Some(s) => {}, // error: use of moved value
     None => {},
 }
 ```

compiler/rustc_feature/src/accepted.rs

@@ -270,6 +270,9 @@ declare_features! (
     (accepted, track_caller, "1.46.0", Some(47809), None),
     /// Allows `#[doc(alias = "...")]`.
     (accepted, doc_alias, "1.48.0", Some(50146), None),
+    /// Allows patterns with concurrent by-move and by-ref bindings.
+    /// For example, you can write `Foo(a, ref b)` where `a` is by-move and `b` is by-ref.
+    (accepted, move_ref_pattern, "1.48.0", Some(68354), None),
 
     // -------------------------------------------------------------------------
     // feature-group-end: accepted features

compiler/rustc_feature/src/active.rs

@@ -526,10 +526,6 @@ declare_features! (
     /// For example, you can write `x @ Some(y)`.
     (active, bindings_after_at, "1.41.0", Some(65490), None),
 
-    /// Allows patterns with concurrent by-move and by-ref bindings.
-    /// For example, you can write `Foo(a, ref b)` where `a` is by-move and `b` is by-ref.
-    (active, move_ref_pattern, "1.42.0", Some(68354), None),
-
     /// Allows `impl const Trait for T` syntax.
     (active, const_trait_impl, "1.42.0", Some(67792), None),
 

compiler/rustc_hir/src/hir.rs

@@ -2742,4 +2742,32 @@ impl<'hir> Node<'hir> {
             _ => None,
         }
     }
+
+    pub fn hir_id(&self) -> Option<HirId> {
+        match self {
+            Node::Item(Item { hir_id, .. })
+            | Node::ForeignItem(ForeignItem { hir_id, .. })
+            | Node::TraitItem(TraitItem { hir_id, .. })
+            | Node::ImplItem(ImplItem { hir_id, .. })
+            | Node::Field(StructField { hir_id, .. })
+            | Node::AnonConst(AnonConst { hir_id, .. })
+            | Node::Expr(Expr { hir_id, .. })
+            | Node::Stmt(Stmt { hir_id, .. })
+            | Node::Ty(Ty { hir_id, .. })
+            | Node::Binding(Pat { hir_id, .. })
+            | Node::Pat(Pat { hir_id, .. })
+            | Node::Arm(Arm { hir_id, .. })
+            | Node::Block(Block { hir_id, .. })
+            | Node::Local(Local { hir_id, .. })
+            | Node::MacroDef(MacroDef { hir_id, .. })
+            | Node::Lifetime(Lifetime { hir_id, .. })
+            | Node::Param(Param { hir_id, .. })
+            | Node::GenericParam(GenericParam { hir_id, .. }) => Some(*hir_id),
+            Node::TraitRef(TraitRef { hir_ref_id, .. }) => Some(*hir_ref_id),
+            Node::PathSegment(PathSegment { hir_id, .. }) => *hir_id,
+            Node::Variant(Variant { id, .. }) => Some(*id),
+            Node::Ctor(variant) => variant.ctor_hir_id(),
+            Node::Crate(_) | Node::Visibility(_) => None,
+        }
+    }
 }

compiler/rustc_middle/src/mir/mod.rs

@@ -1074,6 +1074,23 @@ impl<'tcx> LocalDecl<'tcx> {
     }
 }
 
+#[derive(Clone, TyEncodable, TyDecodable, HashStable, TypeFoldable)]
+pub enum VarDebugInfoContents<'tcx> {
+    /// NOTE(eddyb) There's an unenforced invariant that this `Place` is
+    /// based on a `Local`, not a `Static`, and contains no indexing.
+    Place(Place<'tcx>),
+    Const(Constant<'tcx>),
+}
+
+impl<'tcx> Debug for VarDebugInfoContents<'tcx> {
+    fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            VarDebugInfoContents::Const(c) => write!(fmt, "{}", c),
+            VarDebugInfoContents::Place(p) => write!(fmt, "{:?}", p),
+        }
+    }
+}
+
 /// Debug information pertaining to a user variable.
 #[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable)]
 pub struct VarDebugInfo<'tcx> {
@@ -1085,9 +1102,7 @@ pub struct VarDebugInfo<'tcx> {
     pub source_info: SourceInfo,
 
     /// Where the data for this user variable is to be found.
-    /// NOTE(eddyb) There's an unenforced invariant that this `Place` is
-    /// based on a `Local`, not a `Static`, and contains no indexing.
-    pub place: Place<'tcx>,
+    pub value: VarDebugInfoContents<'tcx>,
 }
 
 ///////////////////////////////////////////////////////////////////////////

compiler/rustc_middle/src/mir/visit.rs

@@ -796,16 +796,20 @@ macro_rules! make_mir_visitor {
                 let VarDebugInfo {
                     name: _,
                     source_info,
-                    place,
+                    value,
                 } = var_debug_info;
 
                 self.visit_source_info(source_info);
                 let location = START_BLOCK.start_location();
-                self.visit_place(
-                    place,
-                    PlaceContext::NonUse(NonUseContext::VarDebugInfo),
-                    location,
-                );
+                match value {
+                    VarDebugInfoContents::Const(c) => self.visit_constant(c, location),
+                    VarDebugInfoContents::Place(place) =>
+                        self.visit_place(
+                            place,
+                            PlaceContext::NonUse(NonUseContext::VarDebugInfo),
+                            location
+                        ),
+                }
             }
 
             fn super_source_scope(&mut self,

compiler/rustc_middle/src/ty/instance.rs

@@ -291,7 +291,17 @@ impl<'tcx> Instance<'tcx> {
     }
 
     pub fn mono(tcx: TyCtxt<'tcx>, def_id: DefId) -> Instance<'tcx> {
-        Instance::new(def_id, tcx.empty_substs_for_def_id(def_id))
+        let substs = InternalSubsts::for_item(tcx, def_id, |param, _| match param.kind {
+            ty::GenericParamDefKind::Lifetime => tcx.lifetimes.re_erased.into(),
+            ty::GenericParamDefKind::Type { .. } => {
+                bug!("Instance::mono: {:?} has type parameters", def_id)
+            }
+            ty::GenericParamDefKind::Const { .. } => {
+                bug!("Instance::mono: {:?} has const parameters", def_id)
+            }
+        });
+
+        Instance::new(def_id, substs)
     }
 
     #[inline]

compiler/rustc_middle/src/ty/query/plumbing.rs

@@ -124,20 +124,23 @@ impl<'tcx> TyCtxt<'tcx> {
         })
     }
 
-    pub fn try_print_query_stack(handler: &Handler) {
+    pub fn try_print_query_stack(handler: &Handler, num_frames: Option<usize>) {
         eprintln!("query stack during panic:");
 
         // Be careful reyling on global state here: this code is called from
         // a panic hook, which means that the global `Handler` may be in a weird
         // state if it was responsible for triggering the panic.
+        let mut i = 0;
         ty::tls::with_context_opt(|icx| {
             if let Some(icx) = icx {
                 let query_map = icx.tcx.queries.try_collect_active_jobs();
 
                 let mut current_query = icx.query;
-                let mut i = 0;
 
                 while let Some(query) = current_query {
+                    if Some(i) == num_frames {
+                        break;
+                    }
                     let query_info =
                         if let Some(info) = query_map.as_ref().and_then(|map| map.get(&query)) {
                             info
@@ -163,7 +166,11 @@ impl<'tcx> TyCtxt<'tcx> {
             }
         });
 
-        eprintln!("end of query stack");
+        if num_frames == None || num_frames >= Some(i) {
+            eprintln!("end of query stack");
+        } else {
+            eprintln!("we're just showing a limited slice of the query stack");
+        }
     }
 }