Auto merge of #108587 - matthiaskrgr:rollup-rw6po59, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - #108376 (compiler/rustc_session: fix sysroot detection logic)
 - #108400 (add llvm cgu instructions stats to perf)
 - #108496 (fix #108495, postfix decrement and prefix decrement has no warning)
 - #108505 (Further unify validity intrinsics)
 - #108520 (Small cleanup to `one_bound_for_assoc_type`)
 - #108560 (Some `infer/mod.rs` cleanups)
 - #108563 (Make mailmap more correct)
 - #108564 (Fix `x clean` with specific paths)
 - #108571 (Add contains_key to SortedIndexMultiMap)
 - #108578 (Update Fuchsia platform team members)

Failed merges:

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

.mailmap

@@ -15,7 +15,7 @@ Adrien Tétar <adri-from-59@hotmail.fr>
 Ahmed Charles <ahmedcharles@gmail.com> <acharles@outlook.com>
 Alan Egerton <eggyal@gmail.com>
 Alan Stoate <alan.stoate@gmail.com>
-Albert Larsan <albert.larsan@gmail.com> Albert Larsan <74931857+albertlarsan68@users.noreply.github.com>
+Albert Larsan <albert.larsan@gmail.com> <74931857+albertlarsan68@users.noreply.github.com>
 Alessandro Decina <alessandro.d@gmail.com>
 Alex Burka <durka42+github@gmail.com> Alex Burka <aburka@seas.upenn.edu>
 Alex Hansen <ahansen2@trinity.edu>

Cargo.lock

@@ -3801,6 +3801,8 @@ dependencies = [
  "rustc_span",
  "rustc_symbol_mangling",
  "rustc_target",
+ "serde",
+ "serde_json",
  "smallvec",
  "tempfile",
  "tracing",

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -22,7 +22,7 @@ pub(crate) use cpuid::codegen_cpuid_call;
 pub(crate) use llvm::codegen_llvm_intrinsic_call;
 
 use rustc_middle::ty;
-use rustc_middle::ty::layout::{HasParamEnv, InitKind};
+use rustc_middle::ty::layout::{HasParamEnv, ValidityRequirement};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_span::symbol::{kw, sym, Symbol};
@@ -628,57 +628,39 @@ fn codegen_regular_intrinsic_call<'tcx>(
             intrinsic_args!(fx, args => (); intrinsic);
 
             let ty = substs.type_at(0);
-            let layout = fx.layout_of(ty);
-            if layout.abi.is_uninhabited() {
-                with_no_trimmed_paths!({
-                    crate::base::codegen_panic_nounwind(
-                        fx,
-                        &format!("attempted to instantiate uninhabited type `{}`", layout.ty),
-                        source_info,
-                    )
-                });
-                return;
-            }
 
-            if intrinsic == sym::assert_zero_valid
-                && !fx
-                    .tcx
-                    .check_validity_of_init((InitKind::Zero, fx.param_env().and(ty)))
-                    .expect("expected to have layout during codegen")
-            {
-                with_no_trimmed_paths!({
-                    crate::base::codegen_panic_nounwind(
-                        fx,
-                        &format!(
-                            "attempted to zero-initialize type `{}`, which is invalid",
-                            layout.ty
-                        ),
-                        source_info,
-                    );
-                });
-                return;
-            }
+            let requirement = ValidityRequirement::from_intrinsic(intrinsic);
 
-            if intrinsic == sym::assert_mem_uninitialized_valid
-                && !fx
+            if let Some(requirement) = requirement {
+                let do_panic = !fx
                     .tcx
-                    .check_validity_of_init((
-                        InitKind::UninitMitigated0x01Fill,
-                        fx.param_env().and(ty),
-                    ))
-                    .expect("expected to have layout during codegen")
-            {
-                with_no_trimmed_paths!({
-                    crate::base::codegen_panic_nounwind(
-                        fx,
-                        &format!(
-                            "attempted to leave type `{}` uninitialized, which is invalid",
-                            layout.ty
-                        ),
-                        source_info,
-                    )
-                });
-                return;
+                    .check_validity_requirement((requirement, fx.param_env().and(ty)))
+                    .expect("expect to have layout during codegen");
+
+                if do_panic {
+                    let layout = fx.layout_of(ty);
+
+                    with_no_trimmed_paths!({
+                        crate::base::codegen_panic_nounwind(
+                            fx,
+                            &if layout.abi.is_uninhabited() {
+                                format!("attempted to instantiate uninhabited type `{}`", layout.ty)
+                            } else if requirement == ValidityRequirement::Zero {
+                                format!(
+                                    "attempted to zero-initialize type `{}`, which is invalid",
+                                    layout.ty
+                                )
+                            } else {
+                                format!(
+                                    "attempted to leave type `{}` uninitialized, which is invalid",
+                                    layout.ty
+                                )
+                            },
+                            source_info,
+                        )
+                    });
+                    return;
+                }
             }
         }
 

compiler/rustc_codegen_llvm/Cargo.toml

@@ -36,3 +36,5 @@ smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
 rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
 tempfile = "3.2.0"
+serde = { version = "1", features = [ "derive" ]}
+serde_json = "1"

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -761,6 +761,7 @@ pub(crate) unsafe fn codegen(
             EmitObj::None => {}
         }
 
+        record_llvm_cgu_instructions_stats(&cgcx.prof, llmod);
         drop(handlers);
     }
 
@@ -974,3 +975,23 @@ fn record_artifact_size(
         self_profiler_ref.artifact_size(artifact_kind, artifact_name.to_string_lossy(), file_size);
     }
 }
+
+fn record_llvm_cgu_instructions_stats(prof: &SelfProfilerRef, llmod: &llvm::Module) {
+    if !prof.enabled() {
+        return;
+    }
+
+    let raw_stats =
+        llvm::build_string(|s| unsafe { llvm::LLVMRustModuleInstructionStats(&llmod, s) })
+            .expect("cannot get module instruction stats");
+
+    #[derive(serde::Deserialize)]
+    struct InstructionsStats {
+        module: String,
+        total: u64,
+    }
+
+    let InstructionsStats { module, total } =
+        serde_json::from_str(&raw_stats).expect("cannot parse llvm cgu instructions stats");
+    prof.artifact_size("cgu_instructions", module, total);
+}

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2410,6 +2410,8 @@ extern "C" {
     pub fn LLVMRustModuleBufferLen(p: &ModuleBuffer) -> usize;
     pub fn LLVMRustModuleBufferFree(p: &'static mut ModuleBuffer);
     pub fn LLVMRustModuleCost(M: &Module) -> u64;
+    #[allow(improper_ctypes)]
+    pub fn LLVMRustModuleInstructionStats(M: &Module, Str: &RustString);
 
     pub fn LLVMRustThinLTOBufferCreate(M: &Module, is_thin: bool) -> &'static mut ThinLTOBuffer;
     pub fn LLVMRustThinLTOBufferFree(M: &'static mut ThinLTOBuffer);

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -14,7 +14,7 @@ use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece};
 use rustc_hir::lang_items::LangItem;
 use rustc_index::vec::Idx;
 use rustc_middle::mir::{self, AssertKind, SwitchTargets};
-use rustc_middle::ty::layout::{HasTyCtxt, InitKind, LayoutOf};
+use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, ValidityRequirement};
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
 use rustc_middle::ty::{self, Instance, Ty, TypeVisitableExt};
 use rustc_session::config::OptLevel;
@@ -655,44 +655,24 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         // Emit a panic or a no-op for `assert_*` intrinsics.
         // These are intrinsics that compile to panics so that we can get a message
         // which mentions the offending type, even from a const context.
-        #[derive(Debug, PartialEq)]
-        enum AssertIntrinsic {
-            Inhabited,
-            ZeroValid,
-            MemUninitializedValid,
-        }
-        let panic_intrinsic = intrinsic.and_then(|i| match i {
-            sym::assert_inhabited => Some(AssertIntrinsic::Inhabited),
-            sym::assert_zero_valid => Some(AssertIntrinsic::ZeroValid),
-            sym::assert_mem_uninitialized_valid => Some(AssertIntrinsic::MemUninitializedValid),
-            _ => None,
-        });
-        if let Some(intrinsic) = panic_intrinsic {
-            use AssertIntrinsic::*;
-
+        let panic_intrinsic = intrinsic.and_then(|s| ValidityRequirement::from_intrinsic(s));
+        if let Some(requirement) = panic_intrinsic {
             let ty = instance.unwrap().substs.type_at(0);
+
+            let do_panic = !bx
+                .tcx()
+                .check_validity_requirement((requirement, bx.param_env().and(ty)))
+                .expect("expect to have layout during codegen");
+
             let layout = bx.layout_of(ty);
-            let do_panic = match intrinsic {
-                Inhabited => layout.abi.is_uninhabited(),
-                ZeroValid => !bx
-                    .tcx()
-                    .check_validity_of_init((InitKind::Zero, bx.param_env().and(ty)))
-                    .expect("expected to have layout during codegen"),
-                MemUninitializedValid => !bx
-                    .tcx()
-                    .check_validity_of_init((
-                        InitKind::UninitMitigated0x01Fill,
-                        bx.param_env().and(ty),
-                    ))
-                    .expect("expected to have layout during codegen"),
-            };
+
             Some(if do_panic {
                 let msg_str = with_no_visible_paths!({
                     with_no_trimmed_paths!({
                         if layout.abi.is_uninhabited() {
                             // Use this error even for the other intrinsics as it is more precise.
                             format!("attempted to instantiate uninhabited type `{}`", ty)
-                        } else if intrinsic == ZeroValid {
+                        } else if requirement == ValidityRequirement::Zero {
                             format!("attempted to zero-initialize type `{}`, which is invalid", ty)
                         } else {
                             format!(

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -11,7 +11,7 @@ use rustc_middle::mir::{
     BinOp, NonDivergingIntrinsic,
 };
 use rustc_middle::ty;
-use rustc_middle::ty::layout::{InitKind, LayoutOf as _};
+use rustc_middle::ty::layout::{LayoutOf as _, ValidityRequirement};
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{Ty, TyCtxt};
 use rustc_span::symbol::{sym, Symbol};
@@ -418,57 +418,35 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             | sym::assert_zero_valid
             | sym::assert_mem_uninitialized_valid => {
                 let ty = instance.substs.type_at(0);
-                let layout = self.layout_of(ty)?;
+                let requirement = ValidityRequirement::from_intrinsic(intrinsic_name).unwrap();
 
-                // For *all* intrinsics we first check `is_uninhabited` to give a more specific
-                // error message.
-                if layout.abi.is_uninhabited() {
-                    // The run-time intrinsic panics just to get a good backtrace; here we abort
-                    // since there is no problem showing a backtrace even for aborts.
-                    M::abort(
-                        self,
-                        format!(
+                let should_panic = !self
+                    .tcx
+                    .check_validity_requirement((requirement, self.param_env.and(ty)))
+                    .map_err(|_| err_inval!(TooGeneric))?;
+
+                if should_panic {
+                    let layout = self.layout_of(ty)?;
+
+                    let msg = match requirement {
+                        // For *all* intrinsics we first check `is_uninhabited` to give a more specific
+                        // error message.
+                        _ if layout.abi.is_uninhabited() => format!(
                             "aborted execution: attempted to instantiate uninhabited type `{}`",
                             ty
                         ),
-                    )?;
-                }
+                        ValidityRequirement::Inhabited => bug!("handled earlier"),
+                        ValidityRequirement::Zero => format!(
+                            "aborted execution: attempted to zero-initialize type `{}`, which is invalid",
+                            ty
+                        ),
+                        ValidityRequirement::UninitMitigated0x01Fill => format!(
+                            "aborted execution: attempted to leave type `{}` uninitialized, which is invalid",
+                            ty
+                        ),
+                    };
 
-                if intrinsic_name == sym::assert_zero_valid {
-                    let should_panic = !self
-                        .tcx
-                        .check_validity_of_init((InitKind::Zero, self.param_env.and(ty)))
-                        .map_err(|_| err_inval!(TooGeneric))?;
-
-                    if should_panic {
-                        M::abort(
-                            self,
-                            format!(
-                                "aborted execution: attempted to zero-initialize type `{}`, which is invalid",
-                                ty
-                            ),
-                        )?;
-                    }
-                }
-
-                if intrinsic_name == sym::assert_mem_uninitialized_valid {
-                    let should_panic = !self
-                        .tcx
-                        .check_validity_of_init((
-                            InitKind::UninitMitigated0x01Fill,
-                            self.param_env.and(ty),
-                        ))
-                        .map_err(|_| err_inval!(TooGeneric))?;
-
-                    if should_panic {
-                        M::abort(
-                            self,
-                            format!(
-                                "aborted execution: attempted to leave type `{}` uninitialized, which is invalid",
-                                ty
-                            ),
-                        )?;
-                    }
+                    M::abort(self, msg)?;
                 }
             }
             sym::simd_insert => {

compiler/rustc_const_eval/src/lib.rs

@@ -61,7 +61,7 @@ pub fn provide(providers: &mut Providers) {
         let (param_env, value) = param_env_and_value.into_parts();
         const_eval::deref_mir_constant(tcx, param_env, value)
     };
-    providers.check_validity_of_init = |tcx, (init_kind, param_env_and_ty)| {
-        util::might_permit_raw_init(tcx, init_kind, param_env_and_ty)
+    providers.check_validity_requirement = |tcx, (init_kind, param_env_and_ty)| {
+        util::check_validity_requirement(tcx, init_kind, param_env_and_ty)
     };
 }

compiler/rustc_const_eval/src/util/check_validity_requirement.rs

@@ -1,4 +1,4 @@
-use rustc_middle::ty::layout::{InitKind, LayoutCx, LayoutError, LayoutOf, TyAndLayout};
+use rustc_middle::ty::layout::{LayoutCx, LayoutError, LayoutOf, TyAndLayout, ValidityRequirement};
 use rustc_middle::ty::{ParamEnv, ParamEnvAnd, Ty, TyCtxt};
 use rustc_session::Limit;
 use rustc_target::abi::{Abi, FieldsShape, Scalar, Variants};
@@ -18,16 +18,23 @@ use crate::interpret::{InterpCx, MemoryKind, OpTy};
 /// Rust UB as long as there is no risk of miscompilations. The `strict_init_checks` can be set to
 /// do a full check against Rust UB instead (in which case we will also ignore the 0x01-filling and
 /// to the full uninit check).
-pub fn might_permit_raw_init<'tcx>(
+pub fn check_validity_requirement<'tcx>(
     tcx: TyCtxt<'tcx>,
-    kind: InitKind,
+    kind: ValidityRequirement,
     param_env_and_ty: ParamEnvAnd<'tcx, Ty<'tcx>>,
 ) -> Result<bool, LayoutError<'tcx>> {
+    let layout = tcx.layout_of(param_env_and_ty)?;
+
+    // There is nothing strict or lax about inhabitedness.
+    if kind == ValidityRequirement::Inhabited {
+        return Ok(!layout.abi.is_uninhabited());
+    }
+
     if tcx.sess.opts.unstable_opts.strict_init_checks {
-        might_permit_raw_init_strict(tcx.layout_of(param_env_and_ty)?, tcx, kind)
+        might_permit_raw_init_strict(layout, tcx, kind)
     } else {
         let layout_cx = LayoutCx { tcx, param_env: param_env_and_ty.param_env };
-        might_permit_raw_init_lax(tcx.layout_of(param_env_and_ty)?, &layout_cx, kind)
+        might_permit_raw_init_lax(layout, &layout_cx, kind)
     }
 }
 
@@ -36,7 +43,7 @@ pub fn might_permit_raw_init<'tcx>(
 fn might_permit_raw_init_strict<'tcx>(
     ty: TyAndLayout<'tcx>,
     tcx: TyCtxt<'tcx>,
-    kind: InitKind,
+    kind: ValidityRequirement,
 ) -> Result<bool, LayoutError<'tcx>> {
     let machine = CompileTimeInterpreter::new(
         Limit::new(0),
@@ -50,7 +57,7 @@ fn might_permit_raw_init_strict<'tcx>(
         .allocate(ty, MemoryKind::Machine(crate::const_eval::MemoryKind::Heap))
         .expect("OOM: failed to allocate for uninit check");
 
-    if kind == InitKind::Zero {
+    if kind == ValidityRequirement::Zero {
         cx.write_bytes_ptr(
             allocated.ptr,
             std::iter::repeat(0_u8).take(ty.layout.size().bytes_usize()),
@@ -72,15 +79,18 @@ fn might_permit_raw_init_strict<'tcx>(
 fn might_permit_raw_init_lax<'tcx>(
     this: TyAndLayout<'tcx>,
     cx: &LayoutCx<'tcx, TyCtxt<'tcx>>,
-    init_kind: InitKind,
+    init_kind: ValidityRequirement,
 ) -> Result<bool, LayoutError<'tcx>> {
     let scalar_allows_raw_init = move |s: Scalar| -> bool {
         match init_kind {
-            InitKind::Zero => {
+            ValidityRequirement::Inhabited => {
+                bug!("ValidityRequirement::Inhabited should have been handled above")
+            }
+            ValidityRequirement::Zero => {
                 // The range must contain 0.
                 s.valid_range(cx).contains(0)
             }
-            InitKind::UninitMitigated0x01Fill => {
+            ValidityRequirement::UninitMitigated0x01Fill => {
                 // The range must include an 0x01-filled buffer.
                 let mut val: u128 = 0x01;
                 for _ in 1..s.size(cx).bytes() {

compiler/rustc_const_eval/src/util/mod.rs

@@ -1,14 +1,14 @@
 mod alignment;
 mod call_kind;
+mod check_validity_requirement;
 pub mod collect_writes;
 mod compare_types;
 mod find_self_call;
-mod might_permit_raw_init;
 mod type_name;
 
 pub use self::alignment::is_disaligned;
 pub use self::call_kind::{call_kind, CallDesugaringKind, CallKind};
+pub use self::check_validity_requirement::check_validity_requirement;
 pub use self::compare_types::{is_equal_up_to_subtyping, is_subtype};
 pub use self::find_self_call::find_self_call;
-pub use self::might_permit_raw_init::might_permit_raw_init;
 pub use self::type_name::type_name;

compiler/rustc_data_structures/src/sorted_map/index_map.rs

@@ -100,6 +100,11 @@ impl<I: Idx, K: Ord, V> SortedIndexMultiMap<I, K, V> {
             (k == &key).then_some((i, v))
         })
     }
+
+    #[inline]
+    pub fn contains_key(&self, key: K) -> bool {
+        self.get_by_key(key).next().is_some()
+    }
 }
 
 impl<I: Idx, K: Eq, V: Eq> Eq for SortedIndexMultiMap<I, K, V> {}

compiler/rustc_data_structures/src/sorted_map/tests.rs

@@ -17,6 +17,10 @@ fn test_sorted_index_multi_map() {
     assert_eq!(set.get_by_key(3).copied().collect::<Vec<_>>(), vec![0]);
     assert!(set.get_by_key(4).next().is_none());
 
+    // `contains_key` works
+    assert!(set.contains_key(3));
+    assert!(!set.contains_key(4));
+
     // `get_by_key` returns items in insertion order.
     let twos: Vec<_> = set.get_by_key_enumerated(2).collect();
     let idxs: Vec<usize> = twos.iter().map(|(i, _)| *i).collect();

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -50,6 +50,7 @@ use rustc_trait_selection::traits::{self, astconv_object_safety_violations, Obli
 
 use smallvec::{smallvec, SmallVec};
 use std::collections::BTreeSet;
+use std::fmt::Display;
 use std::slice;
 
 #[derive(Debug)]
@@ -1095,11 +1096,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 // those that do.
                 self.one_bound_for_assoc_type(
                     || traits::supertraits(tcx, trait_ref),
-                    || trait_ref.print_only_trait_path().to_string(),
+                    trait_ref.print_only_trait_path(),
                     binding.item_name,
                     path_span,
-                    || match binding.kind {
-                        ConvertedBindingKind::Equality(ty) => Some(ty.to_string()),
+                    match binding.kind {
+                        ConvertedBindingKind::Equality(term) => Some(term),
                         _ => None,
                     },
                 )?
@@ -1789,10 +1790,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     assoc_name,
                 )
             },
-            || param_name.to_string(),
+            param_name,
             assoc_name,
             span,
-            || None,
+            None,
         )
     }
 
@@ -1802,10 +1803,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
     fn one_bound_for_assoc_type<I>(
         &self,
         all_candidates: impl Fn() -> I,
-        ty_param_name: impl Fn() -> String,
+        ty_param_name: impl Display,
         assoc_name: Ident,
         span: Span,
-        is_equality: impl Fn() -> Option<String>,
+        is_equality: Option<ty::Term<'tcx>>,
     ) -> Result<ty::PolyTraitRef<'tcx>, ErrorGuaranteed>
     where
         I: Iterator<Item = ty::PolyTraitRef<'tcx>>,
@@ -1821,7 +1822,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             (None, None) => {
                 let reported = self.complain_about_assoc_type_not_found(
                     all_candidates,
-                    &ty_param_name(),
+                    &ty_param_name.to_string(),
                     assoc_name,
                     span,
                 );
@@ -1833,7 +1834,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         if let Some(bound2) = next_cand {
             debug!(?bound2);
 
-            let is_equality = is_equality();
             let bounds = IntoIterator::into_iter([bound, bound2]).chain(matching_candidates);
             let mut err = if is_equality.is_some() {
                 // More specific Error Index entry.
@@ -1843,7 +1843,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     E0222,
                     "ambiguous associated type `{}` in bounds of `{}`",
                     assoc_name,
-                    ty_param_name()
+                    ty_param_name
                 )
             } else {
                 struct_span_err!(
@@ -1852,7 +1852,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     E0221,
                     "ambiguous associated type `{}` in bounds of `{}`",
                     assoc_name,
-                    ty_param_name()
+                    ty_param_name
                 )
             };
             err.span_label(span, format!("ambiguous associated type `{}`", assoc_name));
@@ -1886,18 +1886,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                         err.span_suggestion_verbose(
                             span.with_hi(assoc_name.span.lo()),
                             "use fully qualified syntax to disambiguate",
-                            format!(
-                                "<{} as {}>::",
-                                ty_param_name(),
-                                bound.print_only_trait_path(),
-                            ),
+                            format!("<{} as {}>::", ty_param_name, bound.print_only_trait_path()),
                             Applicability::MaybeIncorrect,
                         );
                     }
                 } else {
                     err.note(&format!(
                         "associated type `{}` could derive from `{}`",
-                        ty_param_name(),
+                        ty_param_name,
                         bound.print_only_trait_path(),
                     ));
                 }
@@ -1906,7 +1902,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 err.help(&format!(
                     "consider introducing a new type parameter `T` and adding `where` constraints:\
                      \n    where\n        T: {},\n{}",
-                    ty_param_name(),
+                    ty_param_name,
                     where_bounds.join(",\n"),
                 ));
             }
@@ -2070,10 +2066,10 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
                 self.one_bound_for_assoc_type(
                     || traits::supertraits(tcx, ty::Binder::dummy(trait_ref.subst_identity())),
-                    || "Self".to_string(),
+                    kw::SelfUpper,
                     assoc_ident,
                     span,
-                    || None,
+                    None,
                 )?
             }
             (

compiler/rustc_infer/src/infer/mod.rs

@@ -156,7 +156,7 @@ pub struct InferCtxtInner<'tcx> {
     undo_log: InferCtxtUndoLogs<'tcx>,
 
     /// Caches for opaque type inference.
-    pub opaque_type_storage: OpaqueTypeStorage<'tcx>,
+    opaque_type_storage: OpaqueTypeStorage<'tcx>,
 }
 
 impl<'tcx> InferCtxtInner<'tcx> {
@@ -195,41 +195,17 @@ impl<'tcx> InferCtxtInner<'tcx> {
     }
 
     #[inline]
-    fn int_unification_table(
-        &mut self,
-    ) -> ut::UnificationTable<
-        ut::InPlace<
-            ty::IntVid,
-            &mut ut::UnificationStorage<ty::IntVid>,
-            &mut InferCtxtUndoLogs<'tcx>,
-        >,
-    > {
+    fn int_unification_table(&mut self) -> UnificationTable<'_, 'tcx, ty::IntVid> {
         self.int_unification_storage.with_log(&mut self.undo_log)
     }
 
     #[inline]
-    fn float_unification_table(
-        &mut self,
-    ) -> ut::UnificationTable<
-        ut::InPlace<
-            ty::FloatVid,
-            &mut ut::UnificationStorage<ty::FloatVid>,
-            &mut InferCtxtUndoLogs<'tcx>,
-        >,
-    > {
+    fn float_unification_table(&mut self) -> UnificationTable<'_, 'tcx, ty::FloatVid> {
         self.float_unification_storage.with_log(&mut self.undo_log)
     }
 
     #[inline]
-    fn const_unification_table(
-        &mut self,
-    ) -> ut::UnificationTable<
-        ut::InPlace<
-            ty::ConstVid<'tcx>,
-            &mut ut::UnificationStorage<ty::ConstVid<'tcx>>,
-            &mut InferCtxtUndoLogs<'tcx>,
-        >,
-    > {
+    fn const_unification_table(&mut self) -> UnificationTable<'_, 'tcx, ty::ConstVid<'tcx>> {
         self.const_unification_storage.with_log(&mut self.undo_log)
     }
 
@@ -1429,17 +1405,14 @@ impl<'tcx> InferCtxt<'tcx> {
         }
     }
 
+    /// Attempts to resolve all type/region/const variables in
+    /// `value`. Region inference must have been run already (e.g.,
+    /// by calling `resolve_regions_and_report_errors`). If some
+    /// variable was never unified, an `Err` results.
+    ///
+    /// This method is idempotent, but it not typically not invoked
+    /// except during the writeback phase.
     pub fn fully_resolve<T: TypeFoldable<TyCtxt<'tcx>>>(&self, value: T) -> FixupResult<'tcx, T> {
-        /*!
-         * Attempts to resolve all type/region/const variables in
-         * `value`. Region inference must have been run already (e.g.,
-         * by calling `resolve_regions_and_report_errors`). If some
-         * variable was never unified, an `Err` results.
-         *
-         * This method is idempotent, but it not typically not invoked
-         * except during the writeback phase.
-         */
-
         let value = resolve::fully_resolve(self, value);
         assert!(
             value.as_ref().map_or(true, |value| !value.needs_infer()),
@@ -1754,7 +1727,6 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
     // in this case. The typechecker should only ever report type errors involving mismatched
     // types using one of these methods, and should not call span_err directly for such
     // errors.
-
     pub fn type_error_struct_with_diag<M>(
         &self,
         sp: Span,

compiler/rustc_llvm/llvm-wrapper/LLVMWrapper.h

@@ -14,6 +14,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/DynamicLibrary.h"
 #include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/JSON.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/Memory.h"
 #include "llvm/Support/SourceMgr.h"

compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp

@@ -1751,6 +1751,19 @@ LLVMRustModuleCost(LLVMModuleRef M) {
   return std::distance(std::begin(f), std::end(f));
 }
 
+extern "C" void
+LLVMRustModuleInstructionStats(LLVMModuleRef M, RustStringRef Str)
+{
+  RawRustStringOstream OS(Str);
+  llvm::json::OStream JOS(OS);
+  auto Module = unwrap(M);
+
+  JOS.object([&] {
+    JOS.attribute("module", Module->getName());
+    JOS.attribute("total", Module->getInstructionCount());
+  });
+}
+
 // Vector reductions:
 extern "C" LLVMValueRef
 LLVMRustBuildVectorReduceFAdd(LLVMBuilderRef B, LLVMValueRef Acc, LLVMValueRef Src) {

compiler/rustc_middle/src/query/keys.rs

@@ -4,7 +4,7 @@ use crate::infer::canonical::Canonical;
 use crate::mir;
 use crate::traits;
 use crate::ty::fast_reject::SimplifiedType;
-use crate::ty::layout::{InitKind, TyAndLayout};
+use crate::ty::layout::{TyAndLayout, ValidityRequirement};
 use crate::ty::subst::{GenericArg, SubstsRef};
 use crate::ty::{self, Ty, TyCtxt};
 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
@@ -698,7 +698,7 @@ impl Key for HirId {
     }
 }
 
-impl<'tcx> Key for (InitKind, ty::ParamEnvAnd<'tcx, Ty<'tcx>>) {
+impl<'tcx> Key for (ValidityRequirement, ty::ParamEnvAnd<'tcx, Ty<'tcx>>) {
     type CacheSelector = DefaultCacheSelector<Self>;
 
     // Just forward to `Ty<'tcx>`

compiler/rustc_middle/src/query/mod.rs

@@ -2166,8 +2166,8 @@ rustc_queries! {
         separate_provide_extern
     }
 
-    query check_validity_of_init(key: (InitKind, ty::ParamEnvAnd<'tcx, Ty<'tcx>>)) -> Result<bool, ty::layout::LayoutError<'tcx>> {
-        desc { "checking to see if `{}` permits being left {}", key.1.value, key.0 }
+    query check_validity_requirement(key: (ValidityRequirement, ty::ParamEnvAnd<'tcx, Ty<'tcx>>)) -> Result<bool, ty::layout::LayoutError<'tcx>> {
+        desc { "checking validity requirement for `{}`: {}", key.1.value, key.0 }
     }
 
     query compare_impl_const(

compiler/rustc_middle/src/ty/layout.rs

@@ -7,6 +7,7 @@ use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_index::vec::Idx;
 use rustc_session::config::OptLevel;
+use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_target::abi::call::FnAbi;
 use rustc_target::abi::*;
@@ -172,16 +173,29 @@ pub const MAX_SIMD_LANES: u64 = 1 << 0xF;
 /// Used in `might_permit_raw_init` to indicate the kind of initialisation
 /// that is checked to be valid
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable)]
-pub enum InitKind {
+pub enum ValidityRequirement {
+    Inhabited,
     Zero,
     UninitMitigated0x01Fill,
 }
 
-impl fmt::Display for InitKind {
+impl ValidityRequirement {
+    pub fn from_intrinsic(intrinsic: Symbol) -> Option<Self> {
+        match intrinsic {
+            sym::assert_inhabited => Some(Self::Inhabited),
+            sym::assert_zero_valid => Some(Self::Zero),
+            sym::assert_mem_uninitialized_valid => Some(Self::UninitMitigated0x01Fill),
+            _ => None,
+        }
+    }
+}
+
+impl fmt::Display for ValidityRequirement {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
-            Self::Zero => f.write_str("zeroed"),
-            Self::UninitMitigated0x01Fill => f.write_str("filled with 0x01"),
+            Self::Inhabited => f.write_str("is inhabited"),
+            Self::Zero => f.write_str("allows being left zeroed"),
+            Self::UninitMitigated0x01Fill => f.write_str("allows being filled with 0x01"),
         }
     }
 }

compiler/rustc_middle/src/ty/query.rs

@@ -32,7 +32,7 @@ use crate::traits::specialization_graph;
 use crate::traits::{self, ImplSource};
 use crate::ty::context::TyCtxtFeed;
 use crate::ty::fast_reject::SimplifiedType;
-use crate::ty::layout::InitKind;
+use crate::ty::layout::ValidityRequirement;
 use crate::ty::subst::{GenericArg, SubstsRef};
 use crate::ty::util::AlwaysRequiresDrop;
 use crate::ty::GeneratorDiagnosticData;

compiler/rustc_mir_transform/src/instcombine.rs

@@ -6,9 +6,9 @@ use rustc_middle::mir::{
     BinOp, Body, Constant, ConstantKind, LocalDecls, Operand, Place, ProjectionElem, Rvalue,
     SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UnOp,
 };
-use rustc_middle::ty::layout::InitKind;
+use rustc_middle::ty::layout::ValidityRequirement;
 use rustc_middle::ty::{self, ParamEnv, SubstsRef, Ty, TyCtxt};
-use rustc_span::symbol::{sym, Symbol};
+use rustc_span::symbol::Symbol;
 
 pub struct InstCombine;
 
@@ -256,16 +256,8 @@ fn intrinsic_assert_panics<'tcx>(
     ty: Ty<'tcx>,
     intrinsic_name: Symbol,
 ) -> Option<bool> {
-    Some(match intrinsic_name {
-        sym::assert_inhabited => tcx.layout_of(param_env.and(ty)).ok()?.abi.is_uninhabited(),
-        sym::assert_zero_valid => {
-            !tcx.check_validity_of_init((InitKind::Zero, param_env.and(ty))).ok()?
-        }
-        sym::assert_mem_uninitialized_valid => !tcx
-            .check_validity_of_init((InitKind::UninitMitigated0x01Fill, param_env.and(ty)))
-            .ok()?,
-        _ => return None,
-    })
+    let requirement = ValidityRequirement::from_intrinsic(intrinsic_name)?;
+    Some(!tcx.check_validity_requirement((requirement, param_env.and(ty))).ok()?)
 }
 
 fn resolve_rust_intrinsic<'tcx>(

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -165,8 +165,6 @@ enum IsStandalone {
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
 enum IncOrDec {
     Inc,
-    // FIXME: `i--` recovery isn't implemented yet
-    #[allow(dead_code)]
     Dec,
 }
 
@@ -1357,6 +1355,20 @@ impl<'a> Parser<'a> {
         self.recover_from_inc_dec(operand_expr, kind, op_span)
     }
 
+    pub(super) fn recover_from_postfix_decrement(
+        &mut self,
+        operand_expr: P<Expr>,
+        op_span: Span,
+        start_stmt: bool,
+    ) -> PResult<'a, P<Expr>> {
+        let kind = IncDecRecovery {
+            standalone: if start_stmt { IsStandalone::Standalone } else { IsStandalone::Subexpr },
+            op: IncOrDec::Dec,
+            fixity: UnaryFixity::Post,
+        };
+        self.recover_from_inc_dec(operand_expr, kind, op_span)
+    }
+
     fn recover_from_inc_dec(
         &mut self,
         base: P<Expr>,

compiler/rustc_parse/src/parser/expr.rs

@@ -282,6 +282,18 @@ impl<'a> Parser<'a> {
                 continue;
             }
 
+            if self.prev_token == token::BinOp(token::Minus)
+                && self.token == token::BinOp(token::Minus)
+                && self.prev_token.span.between(self.token.span).is_empty()
+                && !self.look_ahead(1, |tok| tok.can_begin_expr())
+            {
+                let op_span = self.prev_token.span.to(self.token.span);
+                // Eat the second `-`
+                self.bump();
+                lhs = self.recover_from_postfix_decrement(lhs, op_span, starts_stmt)?;
+                continue;
+            }
+
             let op = op.node;
             // Special cases:
             if op == AssocOp::As {

compiler/rustc_session/src/filesearch.rs

@@ -182,7 +182,17 @@ pub fn get_or_default_sysroot() -> Result<PathBuf, String> {
         if dir.ends_with(crate::config::host_triple()) {
             dir.parent() // chop off `$target`
                 .and_then(|p| p.parent()) // chop off `rustlib`
-                .and_then(|p| p.parent()) // chop off `lib`
+                .and_then(|p| {
+                    // chop off `lib` (this could be also $arch dir if the host sysroot uses a
+                    // multi-arch layout like Debian or Ubuntu)
+                    match p.parent() {
+                        Some(p) => match p.file_name() {
+                            Some(f) if f == "lib" => p.parent(), // first chop went for $arch, so chop again for `lib`
+                            _ => Some(p),
+                        },
+                        None => None,
+                    }
+                })
                 .map(|s| s.to_owned())
                 .ok_or(format!(
                     "Could not move 3 levels upper using `parent()` on {}",

src/bootstrap/clean.rs

@@ -62,6 +62,7 @@ macro_rules! clean_crate_tree {
                 let target = compiler.host;
                 let mut cargo = builder.bare_cargo(compiler, $mode, target, "clean");
                 for krate in &*self.crates {
+                    cargo.arg("-p");
                     cargo.arg(krate);
                 }
 

src/doc/rustc/src/platform-support/fuchsia.md

@@ -12,7 +12,6 @@ The [Fuchsia team]:
 - Tyler Mandry ([@tmandry](https://github.com/tmandry))
 - Dan Johnson ([@computerdruid](https://github.com/computerdruid))
 - David Koloski ([@djkoloski](https://github.com/djkoloski))
-- Andrew Pollack ([@andrewpollack](https://github.com/andrewpollack))
 - Joseph Ryan ([@P1n3appl3](https://github.com/P1n3appl3))
 
 As the team evolves over time, the specific members listed here may differ from

tests/ui/parser/issue-108495-dec.rs

@@ -0,0 +1,39 @@
+fn test0() {
+    let mut i = 0;
+    let _ = i + i--; //~ ERROR Rust has no postfix decrement operator
+    // won't suggest since we can not handle the precedences
+}
+
+fn test1() {
+    let mut i = 0;
+    let _ = i-- + i--; //~ ERROR Rust has no postfix decrement operator
+}
+
+fn test2() {
+    let mut i = 0;
+    let _ = --i + i--; //~ ERROR Rust has no postfix decrement operator
+}
+
+fn test3() {
+    let mut i = 0;
+    let _ = i-- + --i; //~ ERROR Rust has no postfix decrement operator
+}
+
+fn test4() {
+    let mut i = 0;
+    let _ = (1 + 2 + i)--; //~ ERROR Rust has no postfix decrement operator
+}
+
+fn test5() {
+    let mut i = 0;
+    let _ = (i-- + 1) + 2; //~ ERROR Rust has no postfix decrement operator
+}
+
+fn test6(){
+    let i=10;
+    while i != 0 {
+        i--; //~ ERROR Rust has no postfix decrement operator
+    }
+}
+
+fn main() {}

tests/ui/parser/issue-108495-dec.stderr

@@ -0,0 +1,69 @@
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:3:18
+   |
+LL |     let _ = i + i--;
+   |                  ^^ not a valid postfix operator
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:9:14
+   |
+LL |     let _ = i-- + i--;
+   |              ^^ not a valid postfix operator
+   |
+help: use `-= 1` instead
+   |
+LL |     let _ = { let tmp = i; i -= 1; tmp } + i--;
+   |             +++++++++++  ~~~~~~~~~~~~~~~
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:14:20
+   |
+LL |     let _ = --i + i--;
+   |                    ^^ not a valid postfix operator
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:19:14
+   |
+LL |     let _ = i-- + --i;
+   |              ^^ not a valid postfix operator
+   |
+help: use `-= 1` instead
+   |
+LL |     let _ = { let tmp = i; i -= 1; tmp } + --i;
+   |             +++++++++++  ~~~~~~~~~~~~~~~
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:24:24
+   |
+LL |     let _ = (1 + 2 + i)--;
+   |                        ^^ not a valid postfix operator
+   |
+help: use `-= 1` instead
+   |
+LL |     let _ = { let tmp = (1 + 2 + i); (1 + 2 + i) -= 1; tmp };
+   |             +++++++++++            ~~~~~~~~~~~~~~~~~~~~~~~~~
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:29:15
+   |
+LL |     let _ = (i-- + 1) + 2;
+   |               ^^ not a valid postfix operator
+   |
+help: use `-= 1` instead
+   |
+LL |     let _ = ({ let tmp = i; i -= 1; tmp } + 1) + 2;
+   |              +++++++++++  ~~~~~~~~~~~~~~~
+
+error: Rust has no postfix decrement operator
+  --> $DIR/issue-108495-dec.rs:35:10
+   |
+LL |         i--;
+   |          ^^ not a valid postfix operator
+   |
+help: use `-= 1` instead
+   |
+LL |         i -= 1;
+   |           ~~~~
+
+error: aborting due to 7 previous errors
+