Auto merge of #132460 - lcnr:questionable-uwu, r=compiler-errors

Use `TypingMode` throughout the compiler instead of `ParamEnv`

Hopefully the biggest single PR as part of https://github.com/rust-lang/types-team/issues/128.

## `infcx.typing_env` while defining opaque types

I don't know how'll be able to correctly handle opaque types when using something taking a `TypingEnv` while defining opaque types. To correctly handle the opaques we need to be able to pass in the current `opaque_type_storage` and return constraints, i.e. we need to use a proper canonical query. We should migrate all the queries used during HIR typeck and borrowck where this matters to proper canonical queries. This is

## `layout_of` and `Reveal::All`

We convert the `ParamEnv` to `Reveal::All` right at the start of the `layout_of` query, so I've changed callers of `layout_of` to already use a post analysis `TypingEnv` when encountering it.

ca87b535a0/compiler/rustc_ty_utils/src/layout.rs (L51)

## `Ty::is_[unpin|sized|whatever]`

I haven't migrated `fn is_item_raw` to use `TypingEnv`, will do so in a followup PR, this should significantly reduce the amount of `typing_env.param_env`. At some point there will probably be zero such uses as using the type system while ignoring the `typing_mode` is incorrect.

## `MirPhase` and phase-transitions

When inside of a MIR-body, we can mostly use its `MirPhase` to figure out the right `typing_mode`. This does not work during phase transitions, most notably when transitioning from `Analysis` to `Runtime`:

dae7ac133b/compiler/rustc_mir_transform/src/lib.rs (L606-L625)

All these passes still run with `MirPhase::Analysis`, but we should only use `Reveal::All` once we're run the `RevealAll` pass. This required me to manually construct the right `TypingEnv` in all these passes. Given that it feels somewhat easy to accidentally miss this going forward, I would maybe like to change `Body::phase` to an `Option` and replace it at the start of phase transitions. This then makes it clear that the MIR is currently in a weird state.

r? `@ghost`

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -682,8 +682,12 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                 // Normalize before comparing to see through type aliases and projections.
                 let old_ty = ty::EarlyBinder::bind(ty).instantiate(tcx, generic_args);
                 let new_ty = ty::EarlyBinder::bind(ty).instantiate(tcx, new_args);
-                if let Ok(old_ty) = tcx.try_normalize_erasing_regions(self.param_env, old_ty)
-                    && let Ok(new_ty) = tcx.try_normalize_erasing_regions(self.param_env, new_ty)
+                if let Ok(old_ty) =
+                    tcx.try_normalize_erasing_regions(self.infcx.typing_env(self.param_env), old_ty)
+                    && let Ok(new_ty) = tcx.try_normalize_erasing_regions(
+                        self.infcx.typing_env(self.param_env),
+                        new_ty,
+                    )
                 {
                     old_ty == new_ty
                 } else {
@@ -703,7 +707,9 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
             // Test the callee's predicates, substituting in `ref_ty` for the moved argument type.
             clauses.instantiate(tcx, new_args).predicates.iter().all(|&(mut clause)| {
                 // Normalize before testing to see through type aliases and projections.
-                if let Ok(normalized) = tcx.try_normalize_erasing_regions(self.param_env, clause) {
+                if let Ok(normalized) =
+                    tcx.try_normalize_erasing_regions(self.infcx.typing_env(self.param_env), clause)
+                {
                     clause = normalized;
                 }
                 self.infcx.predicate_must_hold_modulo_regions(&Obligation::new(
@@ -3831,11 +3837,16 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
             if tcx.is_diagnostic_item(sym::deref_method, method_did) {
                 let deref_target =
                     tcx.get_diagnostic_item(sym::deref_target).and_then(|deref_target| {
-                        Instance::try_resolve(tcx, self.param_env, deref_target, method_args)
-                            .transpose()
+                        Instance::try_resolve(
+                            tcx,
+                            self.infcx.typing_env(self.param_env),
+                            deref_target,
+                            method_args,
+                        )
+                        .transpose()
                     });
                 if let Some(Ok(instance)) = deref_target {
-                    let deref_target_ty = instance.ty(tcx, self.param_env);
+                    let deref_target_ty = instance.ty(tcx, self.infcx.typing_env(self.param_env));
                     err.note(format!("borrow occurs due to deref coercion to `{deref_target_ty}`"));
                     err.span_note(tcx.def_span(instance.def_id()), "deref defined here");
                 }

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -864,7 +864,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
             let kind = call_kind(
                 self.infcx.tcx,
-                self.param_env,
+                self.infcx.typing_env(self.param_env),
                 method_did,
                 method_args,
                 *fn_span,

compiler/rustc_borrowck/src/diagnostics/region_errors.rs

@@ -952,7 +952,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
             if let Ok(Some(instance)) = ty::Instance::try_resolve(
                 tcx,
-                self.param_env,
+                self.infcx.typing_env(self.param_env),
                 *fn_did,
                 self.infcx.resolve_vars_if_possible(args),
             ) {

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -1527,7 +1527,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 // The signature in this call can reference region variables,
                 // so erase them before calling a query.
                 let output_ty = self.tcx().erase_regions(sig.output());
-                if !output_ty.is_privately_uninhabited(self.tcx(), self.param_env) {
+                if !output_ty
+                    .is_privately_uninhabited(self.tcx(), self.infcx.typing_env(self.param_env))
+                {
                     span_mirbug!(self, term, "call to converging function {:?} w/o dest", sig);
                 }
             }

compiler/rustc_codegen_cranelift/src/abi/mod.rs

@@ -376,7 +376,7 @@ pub(crate) fn codegen_terminator_call<'tcx>(
     let instance = if let ty::FnDef(def_id, fn_args) = *func.layout().ty.kind() {
         let instance = ty::Instance::expect_resolve(
             fx.tcx,
-            ty::ParamEnv::reveal_all(),
+            ty::TypingEnv::fully_monomorphized(),
             def_id,
             fn_args,
             source_info.span,

compiler/rustc_codegen_cranelift/src/base.rs

@@ -666,7 +666,7 @@ fn codegen_stmt<'tcx>(
                             let func_ref = fx.get_function_ref(
                                 Instance::resolve_for_fn_ptr(
                                     fx.tcx,
-                                    ParamEnv::reveal_all(),
+                                    ty::TypingEnv::fully_monomorphized(),
                                     def_id,
                                     args,
                                 )
@@ -841,14 +841,18 @@ fn codegen_stmt<'tcx>(
                     lval.write_cvalue(fx, CValue::by_val(operand, box_layout));
                 }
                 Rvalue::NullaryOp(ref null_op, ty) => {
-                    assert!(lval.layout().ty.is_sized(fx.tcx, ParamEnv::reveal_all()));
+                    assert!(lval.layout().ty.is_sized(fx.tcx, ty::ParamEnv::reveal_all()));
                     let layout = fx.layout_of(fx.monomorphize(ty));
                     let val = match null_op {
                         NullOp::SizeOf => layout.size.bytes(),
                         NullOp::AlignOf => layout.align.abi.bytes(),
                         NullOp::OffsetOf(fields) => fx
                             .tcx
-                            .offset_of_subfield(ParamEnv::reveal_all(), layout, fields.iter())
+                            .offset_of_subfield(
+                                ty::TypingEnv::fully_monomorphized(),
+                                layout,
+                                fields.iter(),
+                            )
                             .bytes(),
                         NullOp::UbChecks => {
                             let val = fx.tcx.sess.ub_checks();

compiler/rustc_codegen_cranelift/src/common.rs

@@ -103,11 +103,11 @@ fn clif_pair_type_from_ty<'tcx>(
 
 /// Is a pointer to this type a wide ptr?
 pub(crate) fn has_ptr_meta<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
-    if ty.is_sized(tcx, ParamEnv::reveal_all()) {
+    if ty.is_sized(tcx, ty::ParamEnv::reveal_all()) {
         return false;
     }
 
-    let tail = tcx.struct_tail_for_codegen(ty, ParamEnv::reveal_all());
+    let tail = tcx.struct_tail_for_codegen(ty, ty::TypingEnv::fully_monomorphized());
     match tail.kind() {
         ty::Foreign(..) => false,
         ty::Str | ty::Slice(..) | ty::Dynamic(..) => true,
@@ -339,9 +339,9 @@ impl<'tcx> rustc_abi::HasDataLayout for FunctionCx<'_, '_, 'tcx> {
     }
 }
 
-impl<'tcx> layout::HasParamEnv<'tcx> for FunctionCx<'_, '_, 'tcx> {
-    fn param_env(&self) -> ParamEnv<'tcx> {
-        ParamEnv::reveal_all()
+impl<'tcx> layout::HasTypingEnv<'tcx> for FunctionCx<'_, '_, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        ty::TypingEnv::fully_monomorphized()
     }
 }
 
@@ -358,7 +358,7 @@ impl<'tcx> FunctionCx<'_, '_, 'tcx> {
     {
         self.instance.instantiate_mir_and_normalize_erasing_regions(
             self.tcx,
-            ty::ParamEnv::reveal_all(),
+            ty::TypingEnv::fully_monomorphized(),
             ty::EarlyBinder::bind(value),
         )
     }
@@ -497,9 +497,9 @@ impl<'tcx> rustc_abi::HasDataLayout for RevealAllLayoutCx<'tcx> {
     }
 }
 
-impl<'tcx> layout::HasParamEnv<'tcx> for RevealAllLayoutCx<'tcx> {
-    fn param_env(&self) -> ParamEnv<'tcx> {
-        ParamEnv::reveal_all()
+impl<'tcx> layout::HasTypingEnv<'tcx> for RevealAllLayoutCx<'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        ty::TypingEnv::fully_monomorphized()
     }
 }
 

compiler/rustc_codegen_cranelift/src/constant.rs

@@ -78,7 +78,7 @@ pub(crate) fn eval_mir_constant<'tcx>(
     let cv = fx.monomorphize(constant.const_);
     // This cannot fail because we checked all required_consts in advance.
     let val = cv
-        .eval(fx.tcx, ty::ParamEnv::reveal_all(), constant.span)
+        .eval(fx.tcx, ty::TypingEnv::fully_monomorphized(), constant.span)
         .expect("erroneous constant missed by mono item collection");
     (val, cv.ty())
 }
@@ -265,8 +265,13 @@ fn data_id_for_static(
         assert!(!definition);
         assert!(!tcx.is_mutable_static(def_id));
 
-        let ty = instance.ty(tcx, ParamEnv::reveal_all());
-        let align = tcx.layout_of(ParamEnv::reveal_all().and(ty)).unwrap().align.pref.bytes();
+        let ty = instance.ty(tcx, ty::TypingEnv::fully_monomorphized());
+        let align = tcx
+            .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty))
+            .unwrap()
+            .align
+            .pref
+            .bytes();
 
         let linkage = if import_linkage == rustc_middle::mir::mono::Linkage::ExternalWeak
             || import_linkage == rustc_middle::mir::mono::Linkage::WeakAny

compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs

@@ -210,7 +210,7 @@ impl DebugContext {
 
         type_names::push_generic_params(
             tcx,
-            tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), args),
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), args),
             &mut name,
         );
 
@@ -275,8 +275,10 @@ impl DebugContext {
         let span = tcx.def_span(def_id);
         let (file_id, line, _column) = self.get_span_loc(tcx, span, span);
 
-        let static_type = Instance::mono(tcx, def_id).ty(tcx, ty::ParamEnv::reveal_all());
-        let static_layout = tcx.layout_of(ty::ParamEnv::reveal_all().and(static_type)).unwrap();
+        let static_type = Instance::mono(tcx, def_id).ty(tcx, ty::TypingEnv::fully_monomorphized());
+        let static_layout = tcx
+            .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(static_type))
+            .unwrap();
         // FIXME use the actual type layout
         let type_id = self.debug_type(tcx, type_dbg, static_type);
 

compiler/rustc_codegen_cranelift/src/inline_asm.rs

@@ -92,7 +92,7 @@ pub(crate) fn codegen_inline_asm_terminator<'tcx>(
                 if let ty::FnDef(def_id, args) = *const_.ty().kind() {
                     let instance = ty::Instance::resolve_for_fn_ptr(
                         fx.tcx,
-                        ty::ParamEnv::reveal_all(),
+                        ty::TypingEnv::fully_monomorphized(),
                         def_id,
                         args,
                     )
@@ -227,11 +227,11 @@ pub(crate) fn codegen_naked_asm<'tcx>(
             InlineAsmOperand::Const { ref value } => {
                 let cv = instance.instantiate_mir_and_normalize_erasing_regions(
                     tcx,
-                    ty::ParamEnv::reveal_all(),
+                    ty::TypingEnv::fully_monomorphized(),
                     ty::EarlyBinder::bind(value.const_),
                 );
                 let const_value = cv
-                    .eval(tcx, ty::ParamEnv::reveal_all(), value.span)
+                    .eval(tcx, ty::TypingEnv::fully_monomorphized(), value.span)
                     .expect("erroneous constant missed by mono item collection");
 
                 let value = rustc_codegen_ssa::common::asm_const_to_str(
@@ -250,13 +250,13 @@ pub(crate) fn codegen_naked_asm<'tcx>(
 
                 let const_ = instance.instantiate_mir_and_normalize_erasing_regions(
                     tcx,
-                    ty::ParamEnv::reveal_all(),
+                    ty::TypingEnv::fully_monomorphized(),
                     ty::EarlyBinder::bind(value.const_),
                 );
                 if let ty::FnDef(def_id, args) = *const_.ty().kind() {
                     let instance = ty::Instance::resolve_for_fn_ptr(
                         tcx,
-                        ty::ParamEnv::reveal_all(),
+                        ty::TypingEnv::fully_monomorphized(),
                         def_id,
                         args,
                     )

compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs

@@ -20,7 +20,7 @@ mod simd;
 use cranelift_codegen::ir::AtomicRmwOp;
 use rustc_middle::ty;
 use rustc_middle::ty::GenericArgsRef;
-use rustc_middle::ty::layout::{HasParamEnv, ValidityRequirement};
+use rustc_middle::ty::layout::ValidityRequirement;
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{Symbol, sym};
@@ -682,7 +682,10 @@ fn codegen_regular_intrinsic_call<'tcx>(
             if let Some(requirement) = requirement {
                 let do_panic = !fx
                     .tcx
-                    .check_validity_requirement((requirement, fx.param_env().and(ty)))
+                    .check_validity_requirement((
+                        requirement,
+                        ty::TypingEnv::fully_monomorphized().as_query_input(ty),
+                    ))
                     .expect("expect to have layout during codegen");
 
                 if do_panic {
@@ -741,7 +744,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
 
             let const_val = fx
                 .tcx
-                .const_eval_instance(ParamEnv::reveal_all(), instance, source_info.span)
+                .const_eval_instance(ty::ParamEnv::reveal_all(), instance, source_info.span)
                 .unwrap();
             let val = crate::constant::codegen_const_value(fx, const_val, ret.layout().ty);
             ret.write_cvalue(fx, val);

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -98,7 +98,7 @@ mod prelude {
     pub(crate) use rustc_middle::mir::{self, *};
     pub(crate) use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
     pub(crate) use rustc_middle::ty::{
-        self, FloatTy, Instance, InstanceKind, IntTy, ParamEnv, Ty, TyCtxt, UintTy,
+        self, FloatTy, Instance, InstanceKind, IntTy, Ty, TyCtxt, UintTy,
     };
     pub(crate) use rustc_span::Span;
 

compiler/rustc_codegen_cranelift/src/main_shim.rs

@@ -49,7 +49,7 @@ pub(crate) fn maybe_create_entry_wrapper(
         // regions must appear in the argument
         // listing.
         let main_ret_ty = tcx.normalize_erasing_regions(
-            ty::ParamEnv::reveal_all(),
+            ty::TypingEnv::fully_monomorphized(),
             main_ret_ty.no_bound_vars().unwrap(),
         );
 
@@ -113,7 +113,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                     .unwrap();
                 let report = Instance::expect_resolve(
                     tcx,
-                    ParamEnv::reveal_all(),
+                    ty::TypingEnv::fully_monomorphized(),
                     report.def_id,
                     tcx.mk_args(&[GenericArg::from(main_ret_ty)]),
                     DUMMY_SP,
@@ -139,7 +139,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                 let start_def_id = tcx.require_lang_item(LangItem::Start, None);
                 let start_instance = Instance::expect_resolve(
                     tcx,
-                    ParamEnv::reveal_all(),
+                    ty::TypingEnv::fully_monomorphized(),
                     start_def_id,
                     tcx.mk_args(&[main_ret_ty.into()]),
                     DUMMY_SP,

compiler/rustc_codegen_cranelift/src/unsize.rs

@@ -3,6 +3,7 @@
 //! [`PointerCoercion::Unsize`]: `rustc_middle::ty::adjustment::PointerCoercion::Unsize`
 
 use rustc_codegen_ssa::base::validate_trivial_unsize;
+use rustc_middle::ty::layout::HasTypingEnv;
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
 
 use crate::base::codegen_panic_nounwind;
@@ -23,7 +24,7 @@ pub(crate) fn unsized_info<'tcx>(
     old_info: Option<Value>,
 ) -> Value {
     let (source, target) =
-        fx.tcx.struct_lockstep_tails_for_codegen(source, target, ParamEnv::reveal_all());
+        fx.tcx.struct_lockstep_tails_for_codegen(source, target, fx.typing_env());
     match (&source.kind(), &target.kind()) {
         (&ty::Array(_, len), &ty::Slice(_)) => fx.bcx.ins().iconst(
             fx.pointer_type,

compiler/rustc_codegen_cranelift/src/value_and_place.rs

@@ -4,6 +4,7 @@ use cranelift_codegen::entity::EntityRef;
 use cranelift_codegen::ir::immediates::Offset32;
 use cranelift_frontend::Variable;
 use rustc_middle::ty::FnSig;
+use rustc_middle::ty::layout::HasTypingEnv;
 
 use crate::prelude::*;
 
@@ -884,19 +885,17 @@ pub(crate) fn assert_assignable<'tcx>(
             assert_assignable(fx, *a, *b, limit - 1);
         }
         (ty::FnPtr(..), ty::FnPtr(..)) => {
-            let from_sig = fx.tcx.normalize_erasing_late_bound_regions(
-                ParamEnv::reveal_all(),
-                from_ty.fn_sig(fx.tcx),
-            );
+            let from_sig = fx
+                .tcx
+                .normalize_erasing_late_bound_regions(fx.typing_env(), from_ty.fn_sig(fx.tcx));
             let FnSig {
                 inputs_and_output: types_from,
                 c_variadic: c_variadic_from,
                 safety: unsafety_from,
                 abi: abi_from,
             } = from_sig;
-            let to_sig = fx
-                .tcx
-                .normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to_ty.fn_sig(fx.tcx));
+            let to_sig =
+                fx.tcx.normalize_erasing_late_bound_regions(fx.typing_env(), to_ty.fn_sig(fx.tcx));
             let FnSig {
                 inputs_and_output: types_to,
                 c_variadic: c_variadic_to,
@@ -932,9 +931,8 @@ pub(crate) fn assert_assignable<'tcx>(
         (&ty::Dynamic(from_traits, _, _from_kind), &ty::Dynamic(to_traits, _, _to_kind)) => {
             // FIXME(dyn-star): Do the right thing with DynKinds
             for (from, to) in from_traits.iter().zip(to_traits) {
-                let from =
-                    fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), from);
-                let to = fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to);
+                let from = fx.tcx.normalize_erasing_late_bound_regions(fx.typing_env(), from);
+                let to = fx.tcx.normalize_erasing_late_bound_regions(fx.typing_env(), to);
                 assert_eq!(
                     from, to,
                     "Can't write trait object of incompatible traits {:?} to place with traits {:?}\n\n{:#?}",

compiler/rustc_codegen_gcc/src/builder.rs

@@ -24,9 +24,9 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::bug;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{
-    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, HasTyCtxt, LayoutError, LayoutOfHelpers,
+    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTyCtxt, HasTypingEnv, LayoutError, LayoutOfHelpers,
 };
-use rustc_middle::ty::{Instance, ParamEnv, Ty, TyCtxt};
+use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_span::Span;
 use rustc_span::def_id::DefId;
 use rustc_target::abi::call::FnAbi;
@@ -2319,9 +2319,9 @@ impl<'a, 'gcc, 'tcx> StaticBuilderMethods for Builder<'a, 'gcc, 'tcx> {
     }
 }
 
-impl<'tcx> HasParamEnv<'tcx> for Builder<'_, '_, 'tcx> {
-    fn param_env(&self) -> ParamEnv<'tcx> {
-        self.cx.param_env()
+impl<'tcx> HasTypingEnv<'tcx> for Builder<'_, '_, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        self.cx.typing_env()
     }
 }
 

compiler/rustc_codegen_gcc/src/consts.rs

@@ -215,7 +215,7 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
         let gcc_type = if nested {
             self.type_i8()
         } else {
-            let ty = instance.ty(self.tcx, ty::ParamEnv::reveal_all());
+            let ty = instance.ty(self.tcx, ty::TypingEnv::fully_monomorphized());
             self.layout_of(ty).gcc_type(self)
         };
 

compiler/rustc_codegen_gcc/src/context.rs

@@ -11,10 +11,10 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::span_bug;
 use rustc_middle::ty::layout::{
-    FnAbiError, FnAbiOf, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, HasTyCtxt, LayoutError,
+    FnAbiError, FnAbiOf, FnAbiOfHelpers, FnAbiRequest, HasTyCtxt, HasTypingEnv, LayoutError,
     LayoutOfHelpers,
 };
-use rustc_middle::ty::{self, Instance, ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, Instance, PolyExistentialTraitRef, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_span::source_map::respan;
 use rustc_span::{DUMMY_SP, Span};
@@ -144,7 +144,9 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
         supports_f128_type: bool,
     ) -> Self {
         let create_type = |ctype, rust_type| {
-            let layout = tcx.layout_of(ParamEnv::reveal_all().and(rust_type)).unwrap();
+            let layout = tcx
+                .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(rust_type))
+                .unwrap();
             let align = layout.align.abi.bytes();
             #[cfg(feature = "master")]
             {
@@ -459,7 +461,7 @@ impl<'gcc, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
             Some(def_id) if !wants_msvc_seh(self.sess()) => {
                 let instance = ty::Instance::expect_resolve(
                     tcx,
-                    ty::ParamEnv::reveal_all(),
+                    self.typing_env(),
                     def_id,
                     ty::List::empty(),
                     DUMMY_SP,
@@ -583,9 +585,9 @@ impl<'gcc, 'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
     }
 }
 
-impl<'tcx, 'gcc> HasParamEnv<'tcx> for CodegenCx<'gcc, 'tcx> {
-    fn param_env(&self) -> ParamEnv<'tcx> {
-        ParamEnv::reveal_all()
+impl<'tcx, 'gcc> HasTypingEnv<'tcx> for CodegenCx<'gcc, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        ty::TypingEnv::fully_monomorphized()
     }
 }
 

compiler/rustc_codegen_gcc/src/int.rs

@@ -5,7 +5,7 @@
 use gccjit::{BinaryOp, ComparisonOp, FunctionType, Location, RValue, ToRValue, Type, UnaryOp};
 use rustc_codegen_ssa::common::{IntPredicate, TypeKind};
 use rustc_codegen_ssa::traits::{BackendTypes, BaseTypeCodegenMethods, BuilderMethods, OverflowOp};
-use rustc_middle::ty::{ParamEnv, Ty};
+use rustc_middle::ty::{self, Ty};
 use rustc_target::abi::Endian;
 use rustc_target::abi::call::{ArgAbi, ArgAttributes, Conv, FnAbi, PassMode};
 use rustc_target::spec;
@@ -380,7 +380,10 @@ impl<'a, 'gcc, 'tcx> Builder<'a, 'gcc, 'tcx> {
         let overflow_field = self.context.new_field(self.location, self.bool_type, "overflow");
 
         let ret_ty = Ty::new_tup(self.tcx, &[self.tcx.types.i128, self.tcx.types.bool]);
-        let layout = self.tcx.layout_of(ParamEnv::reveal_all().and(ret_ty)).unwrap();
+        let layout = self
+            .tcx
+            .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ret_ty))
+            .unwrap();
 
         let arg_abi = ArgAbi { layout, mode: PassMode::Direct(ArgAttributes::new()) };
         let mut fn_abi = FnAbi {

compiler/rustc_codegen_gcc/src/intrinsic/mod.rs

@@ -21,7 +21,7 @@ use rustc_codegen_ssa::traits::{BaseTypeCodegenMethods, MiscCodegenMethods};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::LayoutOf;
 #[cfg(feature = "master")]
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
+use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv};
 use rustc_middle::ty::{self, Instance, Ty};
 use rustc_span::{Span, Symbol, sym};
 use rustc_target::abi::HasDataLayout;
@@ -107,7 +107,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
         span: Span,
     ) -> Result<(), Instance<'tcx>> {
         let tcx = self.tcx;
-        let callee_ty = instance.ty(tcx, ty::ParamEnv::reveal_all());
+        let callee_ty = instance.ty(tcx, self.typing_env());
 
         let (def_id, fn_args) = match *callee_ty.kind() {
             ty::FnDef(def_id, fn_args) => (def_id, fn_args),
@@ -115,7 +115,7 @@ impl<'a, 'gcc, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'a, 'gcc, 'tc
         };
 
         let sig = callee_ty.fn_sig(tcx);
-        let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig);
+        let sig = tcx.normalize_erasing_late_bound_regions(self.typing_env(), sig);
         let arg_tys = sig.inputs();
         let ret_ty = sig.output();
         let name = tcx.item_name(def_id);

compiler/rustc_codegen_gcc/src/intrinsic/simd.rs

@@ -55,8 +55,10 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
     }
 
     let tcx = bx.tcx();
-    let sig =
-        tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), callee_ty.fn_sig(tcx));
+    let sig = tcx.normalize_erasing_late_bound_regions(
+        ty::TypingEnv::fully_monomorphized(),
+        callee_ty.fn_sig(tcx),
+    );
     let arg_tys = sig.inputs();
 
     if name == sym::simd_select_bitmask {
@@ -478,7 +480,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         match *in_elem.kind() {
             ty::RawPtr(p_ty, _) => {
                 let metadata = p_ty.ptr_metadata_ty(bx.tcx, |ty| {
-                    bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty)
+                    bx.tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), ty)
                 });
                 require!(metadata.is_unit(), InvalidMonomorphization::CastWidePointer {
                     span,
@@ -493,7 +495,7 @@ pub fn generic_simd_intrinsic<'a, 'gcc, 'tcx>(
         match *out_elem.kind() {
             ty::RawPtr(p_ty, _) => {
                 let metadata = p_ty.ptr_metadata_ty(bx.tcx, |ty| {
-                    bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty)
+                    bx.tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), ty)
                 });
                 require!(metadata.is_unit(), InvalidMonomorphization::CastWidePointer {
                     span,

compiler/rustc_codegen_gcc/src/mono_item.rs

@@ -6,7 +6,7 @@ use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::mono::{Linkage, Visibility};
-use rustc_middle::ty::layout::{FnAbiOf, LayoutOf};
+use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 
 use crate::context::CodegenCx;
@@ -27,11 +27,8 @@ impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         let DefKind::Static { nested, .. } = self.tcx.def_kind(def_id) else { bug!() };
         // Nested statics do not have a type, so pick a dummy type and let `codegen_static` figure out
         // the gcc type from the actual evaluated initializer.
-        let ty = if nested {
-            self.tcx.types.unit
-        } else {
-            instance.ty(self.tcx, ty::ParamEnv::reveal_all())
-        };
+        let ty =
+            if nested { self.tcx.types.unit } else { instance.ty(self.tcx, self.typing_env()) };
         let gcc_type = self.layout_of(ty).gcc_type(self);
 
         let is_tls = attrs.flags.contains(CodegenFnAttrFlags::THREAD_LOCAL);

compiler/rustc_codegen_llvm/src/builder.rs

@@ -14,7 +14,7 @@ use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_hir::def_id::DefId;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
 use rustc_middle::ty::layout::{
-    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, LayoutError, LayoutOfHelpers,
+    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTypingEnv, LayoutError, LayoutOfHelpers,
     TyAndLayout,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
@@ -81,9 +81,9 @@ impl<'tcx> ty::layout::HasTyCtxt<'tcx> for Builder<'_, '_, 'tcx> {
     }
 }
 
-impl<'tcx> ty::layout::HasParamEnv<'tcx> for Builder<'_, '_, 'tcx> {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        self.cx.param_env()
+impl<'tcx> ty::layout::HasTypingEnv<'tcx> for Builder<'_, '_, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        self.cx.typing_env()
     }
 }
 
@@ -472,7 +472,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
     #[instrument(level = "trace", skip(self))]
     fn load_operand(&mut self, place: PlaceRef<'tcx, &'ll Value>) -> OperandRef<'tcx, &'ll Value> {
         if place.layout.is_unsized() {
-            let tail = self.tcx.struct_tail_for_codegen(place.layout.ty, self.param_env());
+            let tail = self.tcx.struct_tail_for_codegen(place.layout.ty, self.typing_env());
             if matches!(tail.kind(), ty::Foreign(..)) {
                 // Unsized locals and, at least conceptually, even unsized arguments must be copied
                 // around, which requires dynamically determining their size. Therefore, we cannot

compiler/rustc_codegen_llvm/src/callee.rs

@@ -5,7 +5,7 @@
 //! closure.
 
 use rustc_codegen_ssa::common;
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
+use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use tracing::debug;
 
@@ -28,12 +28,7 @@ pub(crate) fn get_fn<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, instance: Instance<'t
     }
 
     let sym = tcx.symbol_name(instance).name;
-    debug!(
-        "get_fn({:?}: {:?}) => {}",
-        instance,
-        instance.ty(cx.tcx(), ty::ParamEnv::reveal_all()),
-        sym
-    );
+    debug!("get_fn({:?}: {:?}) => {}", instance, instance.ty(cx.tcx(), cx.typing_env()), sym);
 
     let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty());
 

compiler/rustc_codegen_llvm/src/consts.rs

@@ -13,8 +13,8 @@ use rustc_middle::mir::interpret::{
     read_target_uint,
 };
 use rustc_middle::mir::mono::MonoItem;
-use rustc_middle::ty::layout::LayoutOf;
-use rustc_middle::ty::{self, Instance};
+use rustc_middle::ty::Instance;
+use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
 use rustc_middle::{bug, span_bug};
 use rustc_session::config::Lto;
 use tracing::{debug, instrument, trace};
@@ -244,7 +244,7 @@ impl<'ll> CodegenCx<'ll, '_> {
         let llty = if nested {
             self.type_i8()
         } else {
-            let ty = instance.ty(self.tcx, ty::ParamEnv::reveal_all());
+            let ty = instance.ty(self.tcx, self.typing_env());
             trace!(?ty);
             self.layout_of(ty).llvm_type(self)
         };

compiler/rustc_codegen_llvm/src/context.rs

@@ -15,7 +15,7 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::middle::codegen_fn_attrs::PatchableFunctionEntry;
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::ty::layout::{
-    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasParamEnv, LayoutError, LayoutOfHelpers,
+    FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTypingEnv, LayoutError, LayoutOfHelpers,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
@@ -658,7 +658,7 @@ impl<'ll, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         let llfn = match tcx.lang_items().eh_personality() {
             Some(def_id) if name.is_none() => self.get_fn_addr(ty::Instance::expect_resolve(
                 tcx,
-                ty::ParamEnv::reveal_all(),
+                self.typing_env(),
                 def_id,
                 ty::List::empty(),
                 DUMMY_SP,
@@ -1162,9 +1162,9 @@ impl<'tcx> ty::layout::HasTyCtxt<'tcx> for CodegenCx<'_, 'tcx> {
     }
 }
 
-impl<'tcx, 'll> HasParamEnv<'tcx> for CodegenCx<'ll, 'tcx> {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        ty::ParamEnv::reveal_all()
+impl<'tcx, 'll> HasTypingEnv<'tcx> for CodegenCx<'ll, 'tcx> {
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        ty::TypingEnv::fully_monomorphized()
     }
 }
 

compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs

@@ -6,7 +6,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_index::Idx;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::{Body, SourceScope};
-use rustc_middle::ty::layout::FnAbiOf;
+use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv};
 use rustc_middle::ty::{self, Instance};
 use rustc_session::config::DebugInfo;
 use rustc_span::BytePos;
@@ -118,7 +118,7 @@ fn make_mir_scope<'ll, 'tcx>(
             // if this is moved to `rustc_codegen_ssa::mir::debuginfo`.
             let callee = cx.tcx.instantiate_and_normalize_erasing_regions(
                 instance.args,
-                ty::ParamEnv::reveal_all(),
+                cx.typing_env(),
                 ty::EarlyBinder::bind(callee),
             );
             debug_context.inlined_function_scopes.entry(callee).or_insert_with(|| {

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -11,10 +11,9 @@ use rustc_codegen_ssa::traits::*;
 use rustc_hir::def::{CtorKind, DefKind};
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
-use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
+use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{
-    self, AdtKind, CoroutineArgsExt, Instance, ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt,
-    Visibility,
+    self, AdtKind, CoroutineArgsExt, Instance, PolyExistentialTraitRef, Ty, TyCtxt, Visibility,
 };
 use rustc_session::config::{self, DebugInfo, Lto};
 use rustc_span::symbol::Symbol;
@@ -301,9 +300,8 @@ fn build_subroutine_type_di_node<'ll, 'tcx>(
         .insert(unique_type_id, recursion_marker_type_di_node(cx));
 
     let fn_ty = unique_type_id.expect_ty();
-    let signature = cx
-        .tcx
-        .normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), fn_ty.fn_sig(cx.tcx));
+    let signature =
+        cx.tcx.normalize_erasing_late_bound_regions(cx.typing_env(), fn_ty.fn_sig(cx.tcx));
 
     let signature_di_nodes: SmallVec<_> = iter::once(
         // return type
@@ -1109,9 +1107,7 @@ fn build_upvar_field_di_nodes<'ll, 'tcx>(
         }
     };
 
-    assert!(
-        up_var_tys.iter().all(|t| t == cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), t))
-    );
+    assert!(up_var_tys.iter().all(|t| t == cx.tcx.normalize_erasing_regions(cx.typing_env(), t)));
 
     let capture_names = cx.tcx.closure_saved_names_of_captured_variables(def_id);
     let layout = cx.layout_of(closure_or_coroutine_ty);
@@ -1272,8 +1268,7 @@ fn build_generic_type_param_di_nodes<'ll, 'tcx>(
             let template_params: SmallVec<_> = iter::zip(args, names)
                 .filter_map(|(kind, name)| {
                     kind.as_type().map(|ty| {
-                        let actual_type =
-                            cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), ty);
+                        let actual_type = cx.tcx.normalize_erasing_regions(cx.typing_env(), ty);
                         let actual_type_di_node = type_di_node(cx, actual_type);
                         let name = name.as_str();
                         unsafe {
@@ -1341,7 +1336,7 @@ pub(crate) fn build_global_var_di_node<'ll>(
     if nested {
         return;
     }
-    let variable_type = Instance::mono(cx.tcx, def_id).ty(cx.tcx, ty::ParamEnv::reveal_all());
+    let variable_type = Instance::mono(cx.tcx, def_id).ty(cx.tcx, cx.typing_env());
     let type_di_node = type_di_node(cx, variable_type);
     let var_name = tcx.item_name(def_id);
     let var_name = var_name.as_str();

compiler/rustc_codegen_llvm/src/debuginfo/metadata/type_map.rs

@@ -6,7 +6,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_macros::HashStable;
 use rustc_middle::bug;
-use rustc_middle::ty::{ParamEnv, PolyExistentialTraitRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, PolyExistentialTraitRef, Ty, TyCtxt};
 
 use super::{SmallVec, UNKNOWN_LINE_NUMBER, unknown_file_metadata};
 use crate::common::{AsCCharPtr, CodegenCx};
@@ -49,12 +49,15 @@ pub(super) enum UniqueTypeId<'tcx> {
 
 impl<'tcx> UniqueTypeId<'tcx> {
     pub(crate) fn for_ty(tcx: TyCtxt<'tcx>, t: Ty<'tcx>) -> Self {
-        assert_eq!(t, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), t));
+        assert_eq!(t, tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), t));
         UniqueTypeId::Ty(t, private::HiddenZst)
     }
 
     pub(crate) fn for_enum_variant_part(tcx: TyCtxt<'tcx>, enum_ty: Ty<'tcx>) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantPart(enum_ty, private::HiddenZst)
     }
 
@@ -63,7 +66,10 @@ impl<'tcx> UniqueTypeId<'tcx> {
         enum_ty: Ty<'tcx>,
         variant_idx: VariantIdx,
     ) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantStructType(enum_ty, variant_idx, private::HiddenZst)
     }
 
@@ -72,7 +78,10 @@ impl<'tcx> UniqueTypeId<'tcx> {
         enum_ty: Ty<'tcx>,
         variant_idx: VariantIdx,
     ) -> Self {
-        assert_eq!(enum_ty, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), enum_ty));
+        assert_eq!(
+            enum_ty,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), enum_ty)
+        );
         UniqueTypeId::VariantStructTypeCppLikeWrapper(enum_ty, variant_idx, private::HiddenZst)
     }
 
@@ -81,10 +90,13 @@ impl<'tcx> UniqueTypeId<'tcx> {
         self_type: Ty<'tcx>,
         implemented_trait: Option<PolyExistentialTraitRef<'tcx>>,
     ) -> Self {
-        assert_eq!(self_type, tcx.normalize_erasing_regions(ParamEnv::reveal_all(), self_type));
+        assert_eq!(
+            self_type,
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), self_type)
+        );
         assert_eq!(
             implemented_trait,
-            tcx.normalize_erasing_regions(ParamEnv::reveal_all(), implemented_trait)
+            tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), implemented_trait)
         );
         UniqueTypeId::VTableTy(self_type, implemented_trait, private::HiddenZst)
     }

compiler/rustc_codegen_llvm/src/debuginfo/mod.rs

@@ -15,8 +15,8 @@ use rustc_data_structures::unord::UnordMap;
 use rustc_hir::def_id::{DefId, DefIdMap};
 use rustc_index::IndexVec;
 use rustc_middle::mir;
-use rustc_middle::ty::layout::LayoutOf;
-use rustc_middle::ty::{self, GenericArgsRef, Instance, ParamEnv, Ty, TypeVisitableExt};
+use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
+use rustc_middle::ty::{self, GenericArgsRef, Instance, Ty, TypeVisitableExt};
 use rustc_session::Session;
 use rustc_session::config::{self, DebugInfo};
 use rustc_span::symbol::Symbol;
@@ -344,7 +344,7 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
 
         type_names::push_generic_params(
             tcx,
-            tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), args),
+            tcx.normalize_erasing_regions(self.typing_env(), args),
             &mut name,
         );
 
@@ -481,8 +481,7 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                 iter::zip(args, names)
                     .filter_map(|(kind, name)| {
                         kind.as_type().map(|ty| {
-                            let actual_type =
-                                cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), ty);
+                            let actual_type = cx.tcx.normalize_erasing_regions(cx.typing_env(), ty);
                             let actual_type_metadata = type_di_node(cx, actual_type);
                             let name = name.as_str();
                             unsafe {
@@ -526,7 +525,7 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                 if cx.tcx.trait_id_of_impl(impl_def_id).is_none() {
                     let impl_self_ty = cx.tcx.instantiate_and_normalize_erasing_regions(
                         instance.args,
-                        ty::ParamEnv::reveal_all(),
+                        cx.typing_env(),
                         cx.tcx.type_of(impl_def_id),
                     );
 

compiler/rustc_codegen_llvm/src/debuginfo/utils.rs

@@ -1,7 +1,7 @@
 // Utility Functions.
 
 use rustc_hir::def_id::DefId;
-use rustc_middle::ty::layout::{HasParamEnv, LayoutOf};
+use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Ty};
 use tracing::trace;
 
@@ -62,7 +62,7 @@ pub(crate) fn wide_pointer_kind<'ll, 'tcx>(
     cx: &CodegenCx<'ll, 'tcx>,
     pointee_ty: Ty<'tcx>,
 ) -> Option<WidePtrKind> {
-    let pointee_tail_ty = cx.tcx.struct_tail_for_codegen(pointee_ty, cx.param_env());
+    let pointee_tail_ty = cx.tcx.struct_tail_for_codegen(pointee_ty, cx.typing_env());
     let layout = cx.layout_of(pointee_tail_ty);
     trace!(
         "wide_pointer_kind: {:?} has layout {:?} (is_unsized? {})",

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -10,7 +10,7 @@ use rustc_codegen_ssa::mir::place::{PlaceRef, PlaceValue};
 use rustc_codegen_ssa::traits::*;
 use rustc_hir as hir;
 use rustc_middle::mir::BinOp;
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, LayoutOf};
+use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, GenericArgsRef, Ty};
 use rustc_middle::{bug, span_bug};
 use rustc_span::{Span, Symbol, sym};
@@ -163,14 +163,14 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
         span: Span,
     ) -> Result<(), ty::Instance<'tcx>> {
         let tcx = self.tcx;
-        let callee_ty = instance.ty(tcx, ty::ParamEnv::reveal_all());
+        let callee_ty = instance.ty(tcx, self.typing_env());
 
         let ty::FnDef(def_id, fn_args) = *callee_ty.kind() else {
             bug!("expected fn item type, found {}", callee_ty);
         };
 
         let sig = callee_ty.fn_sig(tcx);
-        let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig);
+        let sig = tcx.normalize_erasing_late_bound_regions(self.typing_env(), sig);
         let arg_tys = sig.inputs();
         let ret_ty = sig.output();
         let name = tcx.item_name(def_id);
@@ -1152,8 +1152,7 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
     }
 
     let tcx = bx.tcx();
-    let sig =
-        tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), callee_ty.fn_sig(tcx));
+    let sig = tcx.normalize_erasing_late_bound_regions(bx.typing_env(), callee_ty.fn_sig(tcx));
     let arg_tys = sig.inputs();
 
     // Sanity-check: all vector arguments must be immediates.
@@ -2187,7 +2186,7 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
         match in_elem.kind() {
             ty::RawPtr(p_ty, _) => {
                 let metadata = p_ty.ptr_metadata_ty(bx.tcx, |ty| {
-                    bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty)
+                    bx.tcx.normalize_erasing_regions(bx.typing_env(), ty)
                 });
                 require!(metadata.is_unit(), InvalidMonomorphization::CastWidePointer {
                     span,
@@ -2202,7 +2201,7 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
         match out_elem.kind() {
             ty::RawPtr(p_ty, _) => {
                 let metadata = p_ty.ptr_metadata_ty(bx.tcx, |ty| {
-                    bx.tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), ty)
+                    bx.tcx.normalize_erasing_regions(bx.typing_env(), ty)
                 });
                 require!(metadata.is_unit(), InvalidMonomorphization::CastWidePointer {
                     span,

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -3,7 +3,7 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_middle::bug;
 use rustc_middle::mir::mono::{Linkage, Visibility};
-use rustc_middle::ty::layout::{FnAbiOf, LayoutOf};
+use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv, LayoutOf};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use rustc_session::config::CrateType;
 use rustc_target::spec::RelocModel;
@@ -26,11 +26,8 @@ impl<'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'_, 'tcx> {
         let DefKind::Static { nested, .. } = self.tcx.def_kind(def_id) else { bug!() };
         // Nested statics do not have a type, so pick a dummy type and let `codegen_static` figure
         // out the llvm type from the actual evaluated initializer.
-        let ty = if nested {
-            self.tcx.types.unit
-        } else {
-            instance.ty(self.tcx, ty::ParamEnv::reveal_all())
-        };
+        let ty =
+            if nested { self.tcx.types.unit } else { instance.ty(self.tcx, self.typing_env()) };
         let llty = self.layout_of(ty).llvm_type(self);
 
         let g = self.define_global(symbol_name, llty).unwrap_or_else(|| {

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -595,8 +595,10 @@ pub(crate) fn linking_symbol_name_for_instance_in_crate<'tcx>(
 
     let (conv, args) = instance
         .map(|i| {
-            tcx.fn_abi_of_instance(ty::ParamEnv::reveal_all().and((i, ty::List::empty())))
-                .unwrap_or_else(|_| bug!("fn_abi_of_instance({i:?}) failed"))
+            tcx.fn_abi_of_instance(
+                ty::TypingEnv::fully_monomorphized().as_query_input((i, ty::List::empty())),
+            )
+            .unwrap_or_else(|_| bug!("fn_abi_of_instance({i:?}) failed"))
         })
         .map(|fnabi| (fnabi.conv, &fnabi.args[..]))
         .unwrap_or((Conv::Rust, &[]));

compiler/rustc_codegen_ssa/src/base.rs

@@ -21,7 +21,7 @@ use rustc_middle::middle::{exported_symbols, lang_items};
 use rustc_middle::mir::BinOp;
 use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder, MonoItem};
 use rustc_middle::query::Providers;
-use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout};
+use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypingMode};
 use rustc_session::Session;
 use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
@@ -165,7 +165,7 @@ fn unsized_info<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 ) -> Bx::Value {
     let cx = bx.cx();
     let (source, target) =
-        cx.tcx().struct_lockstep_tails_for_codegen(source, target, bx.param_env());
+        cx.tcx().struct_lockstep_tails_for_codegen(source, target, bx.typing_env());
     match (source.kind(), target.kind()) {
         (&ty::Array(_, len), &ty::Slice(_)) => cx.const_usize(
             len.try_to_target_usize(cx.tcx()).expect("expected monomorphic const in codegen"),
@@ -466,10 +466,9 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         // late-bound regions, since late-bound
         // regions must appear in the argument
         // listing.
-        let main_ret_ty = cx.tcx().normalize_erasing_regions(
-            ty::ParamEnv::reveal_all(),
-            main_ret_ty.no_bound_vars().unwrap(),
-        );
+        let main_ret_ty = cx
+            .tcx()
+            .normalize_erasing_regions(cx.typing_env(), main_ret_ty.no_bound_vars().unwrap());
 
         let Some(llfn) = cx.declare_c_main(llfty) else {
             // FIXME: We should be smart and show a better diagnostic here.
@@ -495,7 +494,7 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             let start_def_id = cx.tcx().require_lang_item(LangItem::Start, None);
             let start_instance = ty::Instance::expect_resolve(
                 cx.tcx(),
-                ty::ParamEnv::reveal_all(),
+                cx.typing_env(),
                 start_def_id,
                 cx.tcx().mk_args(&[main_ret_ty.into()]),
                 DUMMY_SP,

compiler/rustc_codegen_ssa/src/debuginfo/type_names.rs

@@ -21,9 +21,7 @@ use rustc_hir::definitions::{DefPathData, DefPathDataName, DisambiguatedDefPathD
 use rustc_hir::{CoroutineDesugaring, CoroutineKind, CoroutineSource, Mutability};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{IntegerExt, TyAndLayout};
-use rustc_middle::ty::{
-    self, ExistentialProjection, GenericArgKind, GenericArgsRef, ParamEnv, Ty, TyCtxt,
-};
+use rustc_middle::ty::{self, ExistentialProjection, GenericArgKind, GenericArgsRef, Ty, TyCtxt};
 use smallvec::SmallVec;
 
 use crate::debuginfo::wants_c_like_enum_debuginfo;
@@ -82,7 +80,7 @@ fn push_debuginfo_type_name<'tcx>(
         ty::Adt(def, args) => {
             // `layout_for_cpp_like_fallback` will be `Some` if we want to use the fallback encoding.
             let layout_for_cpp_like_fallback = if cpp_like_debuginfo && def.is_enum() {
-                match tcx.layout_of(ParamEnv::reveal_all().and(t)) {
+                match tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(t)) {
                     Ok(layout) => {
                         if !wants_c_like_enum_debuginfo(tcx, layout) {
                             Some(layout)
@@ -248,8 +246,10 @@ fn push_debuginfo_type_name<'tcx>(
             };
 
             if let Some(principal) = trait_data.principal() {
-                let principal =
-                    tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), principal);
+                let principal = tcx.normalize_erasing_late_bound_regions(
+                    ty::TypingEnv::fully_monomorphized(),
+                    principal,
+                );
                 push_item_name(tcx, principal.def_id, qualified, output);
                 let principal_has_generic_params =
                     push_generic_params_internal(tcx, principal.args, output, visited);
@@ -350,8 +350,10 @@ fn push_debuginfo_type_name<'tcx>(
                 return;
             }
 
-            let sig =
-                tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), t.fn_sig(tcx));
+            let sig = tcx.normalize_erasing_late_bound_regions(
+                ty::TypingEnv::fully_monomorphized(),
+                t.fn_sig(tcx),
+            );
 
             if cpp_like_debuginfo {
                 // Format as a C++ function pointer: return_type (*)(params...)
@@ -415,7 +417,8 @@ fn push_debuginfo_type_name<'tcx>(
             // In the case of cpp-like debuginfo, the name additionally gets wrapped inside of
             // an artificial `enum2$<>` type, as defined in msvc_enum_fallback().
             if cpp_like_debuginfo && t.is_coroutine() {
-                let ty_and_layout = tcx.layout_of(ParamEnv::reveal_all().and(t)).unwrap();
+                let ty_and_layout =
+                    tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(t)).unwrap();
                 msvc_enum_fallback(
                     tcx,
                     ty_and_layout,
@@ -529,8 +532,8 @@ pub fn compute_debuginfo_vtable_name<'tcx>(
     }
 
     if let Some(trait_ref) = trait_ref {
-        let trait_ref =
-            tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), trait_ref);
+        let trait_ref = tcx
+            .normalize_erasing_late_bound_regions(ty::TypingEnv::fully_monomorphized(), trait_ref);
         push_item_name(tcx, trait_ref.def_id, true, &mut vtable_name);
         visited.clear();
         push_generic_params_internal(tcx, trait_ref.args, &mut vtable_name, &mut visited);
@@ -639,7 +642,7 @@ fn push_generic_params_internal<'tcx>(
     output: &mut String,
     visited: &mut FxHashSet<Ty<'tcx>>,
 ) -> bool {
-    assert_eq!(args, tcx.normalize_erasing_regions(ty::ParamEnv::reveal_all(), args));
+    assert_eq!(args, tcx.normalize_erasing_regions(ty::TypingEnv::fully_monomorphized(), args));
     let mut args = args.non_erasable_generics().peekable();
     if args.peek().is_none() {
         return false;
@@ -678,14 +681,14 @@ fn push_const_param<'tcx>(tcx: TyCtxt<'tcx>, ct: ty::Const<'tcx>, output: &mut S
                     // FIXME: directly extract the bits from a valtree instead of evaluating an
                     // already evaluated `Const` in order to get the bits.
                     let bits = ct
-                        .try_to_bits(tcx, ty::ParamEnv::reveal_all())
+                        .try_to_bits(tcx, ty::TypingEnv::fully_monomorphized())
                         .expect("expected monomorphic const in codegen");
                     let val = Integer::from_int_ty(&tcx, *ity).size().sign_extend(bits) as i128;
                     write!(output, "{val}")
                 }
                 ty::Uint(_) => {
                     let val = ct
-                        .try_to_bits(tcx, ty::ParamEnv::reveal_all())
+                        .try_to_bits(tcx, ty::TypingEnv::fully_monomorphized())
                         .expect("expected monomorphic const in codegen");
                     write!(output, "{val}")
                 }

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -777,7 +777,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             let do_panic = !bx
                 .tcx()
-                .check_validity_requirement((requirement, bx.param_env().and(ty)))
+                .check_validity_requirement((requirement, bx.typing_env().as_query_input(ty)))
                 .expect("expect to have layout during codegen");
 
             let layout = bx.layout_of(ty);
@@ -848,14 +848,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         let (instance, mut llfn) = match *callee.layout.ty.kind() {
             ty::FnDef(def_id, args) => (
                 Some(
-                    ty::Instance::expect_resolve(
-                        bx.tcx(),
-                        ty::ParamEnv::reveal_all(),
-                        def_id,
-                        args,
-                        fn_span,
-                    )
-                    .polymorphize(bx.tcx()),
+                    ty::Instance::expect_resolve(bx.tcx(), bx.typing_env(), def_id, args, fn_span)
+                        .polymorphize(bx.tcx()),
                 ),
                 None,
             ),
@@ -1191,7 +1185,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     if let ty::FnDef(def_id, args) = *const_.ty().kind() {
                         let instance = ty::Instance::resolve_for_fn_ptr(
                             bx.tcx(),
-                            ty::ParamEnv::reveal_all(),
+                            bx.typing_env(),
                             def_id,
                             args,
                         )

compiler/rustc_codegen_ssa/src/mir/constant.rs

@@ -1,6 +1,6 @@
 use rustc_abi::BackendRepr;
 use rustc_middle::mir::interpret::ErrorHandled;
-use rustc_middle::ty::layout::HasTyCtxt;
+use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv};
 use rustc_middle::ty::{self, Ty};
 use rustc_middle::{bug, mir, span_bug};
 
@@ -24,7 +24,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         // `MirUsedCollector` visited all required_consts before codegen began, so if we got here
         // there can be no more constants that fail to evaluate.
         self.monomorphize(constant.const_)
-            .eval(self.cx.tcx(), ty::ParamEnv::reveal_all(), constant.span)
+            .eval(self.cx.tcx(), self.cx.typing_env(), constant.span)
             .expect("erroneous constant missed by mono item collection")
     }
 
@@ -57,7 +57,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             other => span_bug!(constant.span, "{other:#?}"),
         };
         let uv = self.monomorphize(uv);
-        self.cx.tcx().const_eval_resolve_for_typeck(ty::ParamEnv::reveal_all(), uv, constant.span)
+        self.cx.tcx().const_eval_resolve_for_typeck(self.cx.typing_env(), uv, constant.span)
     }
 
     /// process constant containing SIMD shuffle indices & constant vectors

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -59,14 +59,14 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         llresult: Bx::Value,
         span: Span,
     ) -> Result<(), ty::Instance<'tcx>> {
-        let callee_ty = instance.ty(bx.tcx(), ty::ParamEnv::reveal_all());
+        let callee_ty = instance.ty(bx.tcx(), bx.typing_env());
 
         let ty::FnDef(def_id, fn_args) = *callee_ty.kind() else {
             bug!("expected fn item type, found {}", callee_ty);
         };
 
         let sig = callee_ty.fn_sig(bx.tcx());
-        let sig = bx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), sig);
+        let sig = bx.tcx().normalize_erasing_late_bound_regions(bx.typing_env(), sig);
         let arg_tys = sig.inputs();
         let ret_ty = sig.output();
         let name = bx.tcx().item_name(def_id);

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -4,7 +4,7 @@ use rustc_index::IndexVec;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::{UnwindTerminateReason, traversal};
-use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, TyAndLayout};
+use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, TyAndLayout};
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
 use rustc_middle::{bug, mir, span_bug};
 use rustc_target::callconv::{FnAbi, PassMode};
@@ -128,7 +128,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         debug!("monomorphize: self.instance={:?}", self.instance);
         self.instance.instantiate_mir_and_normalize_erasing_regions(
             self.cx.tcx(),
-            ty::ParamEnv::reveal_all(),
+            self.cx.typing_env(),
             ty::EarlyBinder::bind(value),
         )
     }

compiler/rustc_codegen_ssa/src/mir/rvalue.rs

@@ -474,7 +474,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                             ty::FnDef(def_id, args) => {
                                 let instance = ty::Instance::resolve_for_fn_ptr(
                                     bx.tcx(),
-                                    ty::ParamEnv::reveal_all(),
+                                    bx.typing_env(),
                                     def_id,
                                     args,
                                 )
@@ -709,7 +709,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     mir::NullOp::OffsetOf(fields) => {
                         let val = bx
                             .tcx()
-                            .offset_of_subfield(bx.param_env(), layout, fields.iter())
+                            .offset_of_subfield(bx.typing_env(), layout, fields.iter())
                             .bytes();
                         bx.cx().const_usize(val)
                     }
@@ -727,7 +727,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
             mir::Rvalue::ThreadLocalRef(def_id) => {
                 assert!(bx.cx().tcx().is_static(def_id));
-                let layout = bx.layout_of(bx.cx().tcx().static_ptr_ty(def_id));
+                let layout = bx.layout_of(bx.cx().tcx().static_ptr_ty(def_id, bx.typing_env()));
                 let static_ = if !def_id.is_local() && bx.cx().tcx().needs_thread_local_shim(def_id)
                 {
                     let instance = ty::Instance {

compiler/rustc_codegen_ssa/src/traits/type_.rs

@@ -1,6 +1,6 @@
 use rustc_abi::{AddressSpace, Float, Integer};
 use rustc_middle::bug;
-use rustc_middle::ty::layout::{HasTyCtxt, TyAndLayout};
+use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv, TyAndLayout};
 use rustc_middle::ty::{self, Ty};
 use rustc_target::callconv::{ArgAbi, CastTarget, FnAbi, Reg};
 
@@ -41,7 +41,7 @@ pub trait BaseTypeCodegenMethods<'tcx>: BackendTypes {
 }
 
 pub trait DerivedTypeCodegenMethods<'tcx>:
-    BaseTypeCodegenMethods<'tcx> + MiscCodegenMethods<'tcx> + HasTyCtxt<'tcx>
+    BaseTypeCodegenMethods<'tcx> + MiscCodegenMethods<'tcx> + HasTyCtxt<'tcx> + HasTypingEnv<'tcx>
 {
     fn type_int(&self) -> Self::Type {
         match &self.sess().target.c_int_width[..] {
@@ -74,7 +74,7 @@ pub trait DerivedTypeCodegenMethods<'tcx>:
     }
 
     fn type_needs_drop(&self, ty: Ty<'tcx>) -> bool {
-        ty.needs_drop(self.tcx(), ty::ParamEnv::reveal_all())
+        ty.needs_drop(self.tcx(), self.typing_env())
     }
 
     fn type_is_sized(&self, ty: Ty<'tcx>) -> bool {
@@ -86,12 +86,11 @@ pub trait DerivedTypeCodegenMethods<'tcx>:
     }
 
     fn type_has_metadata(&self, ty: Ty<'tcx>) -> bool {
-        let param_env = ty::ParamEnv::reveal_all();
-        if ty.is_sized(self.tcx(), param_env) {
+        if ty.is_sized(self.tcx(), self.param_env()) {
             return false;
         }
 
-        let tail = self.tcx().struct_tail_for_codegen(ty, param_env);
+        let tail = self.tcx().struct_tail_for_codegen(ty, self.typing_env());
         match tail.kind() {
             ty::Foreign(..) => false,
             ty::Str | ty::Slice(..) | ty::Dynamic(..) => true,
@@ -101,7 +100,10 @@ pub trait DerivedTypeCodegenMethods<'tcx>:
 }
 
 impl<'tcx, T> DerivedTypeCodegenMethods<'tcx> for T where
-    Self: BaseTypeCodegenMethods<'tcx> + MiscCodegenMethods<'tcx> + HasTyCtxt<'tcx>
+    Self: BaseTypeCodegenMethods<'tcx>
+        + MiscCodegenMethods<'tcx>
+        + HasTyCtxt<'tcx>
+        + HasTypingEnv<'tcx>
 {
 }
 

compiler/rustc_const_eval/src/check_consts/check.rs

@@ -388,7 +388,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
             return false;
         }
 
-        let infcx = tcx.infer_ctxt().build(self.body.typing_mode(tcx));
+        let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(self.body.typing_env(tcx));
         let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
         let body_id = self.body.source.def_id().expect_local();
@@ -398,11 +398,8 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
                 ty::BoundConstness::Const
             }
         };
-        let const_conditions = ocx.normalize(
-            &ObligationCause::misc(call_span, body_id),
-            self.param_env,
-            const_conditions,
-        );
+        let const_conditions =
+            ocx.normalize(&ObligationCause::misc(call_span, body_id), param_env, const_conditions);
         ocx.register_obligations(const_conditions.into_iter().map(|(trait_ref, span)| {
             Obligation::new(
                 tcx,
@@ -411,7 +408,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
                     body_id,
                     ObligationCauseCode::WhereClause(callee, span),
                 ),
-                self.param_env,
+                param_env,
                 trait_ref.to_host_effect_clause(tcx, host_polarity),
             )
         }));

compiler/rustc_const_eval/src/check_consts/mod.rs

@@ -24,17 +24,15 @@ mod resolver;
 pub struct ConstCx<'mir, 'tcx> {
     pub body: &'mir mir::Body<'tcx>,
     pub tcx: TyCtxt<'tcx>,
-    pub param_env: ty::ParamEnv<'tcx>,
+    pub typing_env: ty::TypingEnv<'tcx>,
     pub const_kind: Option<hir::ConstContext>,
 }
 
 impl<'mir, 'tcx> ConstCx<'mir, 'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>, body: &'mir mir::Body<'tcx>) -> Self {
-        let def_id = body.source.def_id().expect_local();
-        let param_env = tcx.param_env(def_id);
-
+        let typing_env = body.typing_env(tcx);
         let const_kind = tcx.hir().body_const_context(body.source.def_id().expect_local());
-        ConstCx { body, tcx, param_env, const_kind }
+        ConstCx { body, tcx, typing_env, const_kind }
     }
 
     pub(crate) fn dcx(&self) -> DiagCtxtHandle<'tcx> {

compiler/rustc_const_eval/src/check_consts/ops.rs

@@ -120,7 +120,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
     #[allow(rustc::untranslatable_diagnostic)]
     fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> {
         let FnCallNonConst { callee, args, span, call_source } = *self;
-        let ConstCx { tcx, param_env, .. } = *ccx;
+        let ConstCx { tcx, typing_env, .. } = *ccx;
         let caller = ccx.def_id();
 
         let diag_trait = |err, self_ty: Ty<'_>, trait_id| {
@@ -146,13 +146,11 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
                     }
                 }
                 ty::Adt(..) => {
+                    let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env);
                     let obligation =
                         Obligation::new(tcx, ObligationCause::dummy(), param_env, trait_ref);
-
-                    let infcx = tcx.infer_ctxt().build(ccx.body.typing_mode(tcx));
                     let mut selcx = SelectionContext::new(&infcx);
                     let implsrc = selcx.select(&obligation);
-
                     if let Ok(Some(ImplSource::UserDefined(data))) = implsrc {
                         // FIXME(const_trait_impl) revisit this
                         if !tcx.is_const_trait_impl(data.impl_def_id) {
@@ -166,7 +164,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
         };
 
         let call_kind =
-            call_kind(tcx, ccx.param_env, callee, args, span, call_source.from_hir_call(), None);
+            call_kind(tcx, ccx.typing_env, callee, args, span, call_source.from_hir_call(), None);
 
         debug!(?call_kind);
 

compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs

@@ -32,17 +32,15 @@ pub fn checking_enabled(ccx: &ConstCx<'_, '_>) -> bool {
 /// This is separate from the rest of the const checking logic because it must run after drop
 /// elaboration.
 pub fn check_live_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>) {
-    let def_id = body.source.def_id().expect_local();
-    let const_kind = tcx.hir().body_const_context(def_id);
-    if const_kind.is_none() {
+    let ccx = ConstCx::new(tcx, body);
+    if ccx.const_kind.is_none() {
         return;
     }
 
-    if tcx.has_attr(def_id, sym::rustc_do_not_const_check) {
+    if tcx.has_attr(body.source.def_id(), sym::rustc_do_not_const_check) {
         return;
     }
 
-    let ccx = ConstCx { body, tcx, const_kind, param_env: tcx.param_env(def_id) };
     if !checking_enabled(&ccx) {
         return;
     }

compiler/rustc_const_eval/src/check_consts/qualifs.rs

@@ -106,20 +106,24 @@ impl Qualif for HasMutInterior {
         // Instead we invoke an obligation context manually, and provide the opaque type inference settings
         // that allow the trait solver to just error out instead of cycling.
         let freeze_def_id = cx.tcx.require_lang_item(LangItem::Freeze, Some(cx.body.span));
-
+        // FIXME(#132279): Once we've got a typing mode which reveals opaque types using the HIR
+        // typeck results without causing query cycles, we should use this here instead of defining
+        // opaque types.
+        let typing_env = ty::TypingEnv {
+            typing_mode: ty::TypingMode::analysis_in_body(
+                cx.tcx,
+                cx.body.source.def_id().expect_local(),
+            ),
+            param_env: cx.typing_env.param_env,
+        };
+        let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(typing_env);
+        let ocx = ObligationCtxt::new(&infcx);
         let obligation = Obligation::new(
             cx.tcx,
             ObligationCause::dummy_with_span(cx.body.span),
-            cx.param_env,
+            param_env,
             ty::TraitRef::new(cx.tcx, freeze_def_id, [ty::GenericArg::from(ty)]),
         );
-
-        // FIXME(#132279): This should eventually use the already defined hidden types.
-        let infcx = cx.tcx.infer_ctxt().build(ty::TypingMode::analysis_in_body(
-            cx.tcx,
-            cx.body.source.def_id().expect_local(),
-        ));
-        let ocx = ObligationCtxt::new(&infcx);
         ocx.register_obligation(obligation);
         let errors = ocx.select_all_or_error();
         !errors.is_empty()
@@ -156,7 +160,7 @@ impl Qualif for NeedsDrop {
     }
 
     fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool {
-        ty.needs_drop(cx.tcx, cx.param_env)
+        ty.needs_drop(cx.tcx, cx.typing_env)
     }
 
     fn in_adt_inherently<'tcx>(

compiler/rustc_const_eval/src/check_consts/resolver.rs

@@ -120,7 +120,10 @@ where
     ///
     /// [rust-lang/unsafe-code-guidelines#134]: https://github.com/rust-lang/unsafe-code-guidelines/issues/134
     fn shared_borrow_allows_mutation(&self, place: mir::Place<'tcx>) -> bool {
-        !place.ty(self.ccx.body, self.ccx.tcx).ty.is_freeze(self.ccx.tcx, self.ccx.param_env)
+        !place
+            .ty(self.ccx.body, self.ccx.tcx)
+            .ty
+            .is_freeze(self.ccx.tcx, self.ccx.typing_env.param_env)
     }
 }
 

compiler/rustc_const_eval/src/const_eval/eval_queries.rs

@@ -221,7 +221,7 @@ pub(super) fn op_to_const<'tcx>(
                 let pointee_ty = imm.layout.ty.builtin_deref(false).unwrap(); // `false` = no raw ptrs
                 debug_assert!(
                     matches!(
-                        ecx.tcx.struct_tail_for_codegen(pointee_ty, ecx.param_env).kind(),
+                        ecx.tcx.struct_tail_for_codegen(pointee_ty, ecx.typing_env()).kind(),
                         ty::Str | ty::Slice(..),
                     ),
                     "`ConstValue::Slice` is for slice-tailed types only, but got {}",
@@ -280,11 +280,13 @@ pub fn eval_to_const_value_raw_provider<'tcx>(
     // opaque types. This is needed for trivial things like `size_of`, but also for using associated
     // types that are not specified in the opaque type.
     assert_eq!(key.param_env.reveal(), Reveal::All);
+    let typing_env =
+        ty::TypingEnv { typing_mode: ty::TypingMode::PostAnalysis, param_env: key.param_env };
 
     // We call `const_eval` for zero arg intrinsics, too, in order to cache their value.
     // Catch such calls and evaluate them instead of trying to load a constant's MIR.
     if let ty::InstanceKind::Intrinsic(def_id) = key.value.instance.def {
-        let ty = key.value.instance.ty(tcx, key.param_env);
+        let ty = key.value.instance.ty(tcx, typing_env);
         let ty::FnDef(_, args) = ty.kind() else {
             bug!("intrinsic with type {:?}", ty);
         };

compiler/rustc_const_eval/src/const_eval/machine.rs

@@ -249,9 +249,10 @@ impl<'tcx> CompileTimeInterpCx<'tcx> {
         } else if self.tcx.is_lang_item(def_id, LangItem::PanicFmt) {
             // For panic_fmt, call const_panic_fmt instead.
             let const_def_id = self.tcx.require_lang_item(LangItem::ConstPanicFmt, None);
+            // FIXME(@lcnr): why does this use an empty env if we've got a `param_env` right here.
             let new_instance = ty::Instance::expect_resolve(
                 *self.tcx,
-                ty::ParamEnv::reveal_all(),
+                ty::TypingEnv::fully_monomorphized(),
                 const_def_id,
                 instance.args,
                 self.cur_span(),

compiler/rustc_const_eval/src/const_eval/valtrees.rs

@@ -2,6 +2,7 @@ use rustc_abi::{BackendRepr, VariantIdx};
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_middle::mir::interpret::{EvalToValTreeResult, GlobalId};
 use rustc_middle::ty::layout::{LayoutCx, LayoutOf, TyAndLayout};
+use rustc_middle::ty::solve::Reveal;
 use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt};
 use rustc_middle::{bug, mir};
 use rustc_span::DUMMY_SP;
@@ -281,8 +282,9 @@ pub fn valtree_to_const_value<'tcx>(
     // the `ValTree` and using `place_projection` and `place_field` to
     // create inner `MPlace`s which are filled recursively.
     // FIXME Does this need an example?
-
     let (param_env, ty) = param_env_ty.into_parts();
+    debug_assert_eq!(param_env.reveal(), Reveal::All);
+    let typing_env = ty::TypingEnv { typing_mode: ty::TypingMode::PostAnalysis, param_env };
 
     match *ty.kind() {
         ty::FnDef(..) => {
@@ -302,11 +304,12 @@ pub fn valtree_to_const_value<'tcx>(
             let mut ecx =
                 mk_eval_cx_to_read_const_val(tcx, DUMMY_SP, param_env, CanAccessMutGlobal::No);
             let imm = valtree_to_ref(&mut ecx, valtree, inner_ty);
-            let imm = ImmTy::from_immediate(imm, tcx.layout_of(param_env_ty).unwrap());
+            let imm =
+                ImmTy::from_immediate(imm, tcx.layout_of(typing_env.as_query_input(ty)).unwrap());
             op_to_const(&ecx, &imm.into(), /* for diagnostics */ false)
         }
         ty::Tuple(_) | ty::Array(_, _) | ty::Adt(..) => {
-            let layout = tcx.layout_of(param_env_ty).unwrap();
+            let layout = tcx.layout_of(typing_env.as_query_input(ty)).unwrap();
             if layout.is_zst() {
                 // Fast path to avoid some allocations.
                 return mir::ConstValue::ZeroSized;
@@ -319,7 +322,7 @@ pub fn valtree_to_const_value<'tcx>(
                 let branches = valtree.unwrap_branch();
                 // Find the non-ZST field. (There can be aligned ZST!)
                 for (i, &inner_valtree) in branches.iter().enumerate() {
-                    let field = layout.field(&LayoutCx::new(tcx, param_env), i);
+                    let field = layout.field(&LayoutCx::new(tcx, typing_env), i);
                     if !field.is_zst() {
                         return valtree_to_const_value(tcx, param_env.and(field.ty), inner_valtree);
                     }

compiler/rustc_const_eval/src/interpret/call.rs

@@ -215,7 +215,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 // Even if `ty` is normalized, the search for the unsized tail will project
                 // to fields, which can yield non-normalized types. So we need to provide a
                 // normalization function.
-                let normalize = |ty| self.tcx.normalize_erasing_regions(self.param_env, ty);
+                let normalize = |ty| self.tcx.normalize_erasing_regions(self.typing_env(), ty);
                 ty.ptr_metadata_ty(*self.tcx, normalize)
             };
             return interp_ok(meta_ty(caller) == meta_ty(callee));
@@ -652,35 +652,35 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 };
 
                 // Obtain the underlying trait we are working on, and the adjusted receiver argument.
-                let (trait_, dyn_ty, adjusted_recv) = if let ty::Dynamic(data, _, ty::DynStar) =
-                    receiver_place.layout.ty.kind()
-                {
-                    let recv = self.unpack_dyn_star(&receiver_place, data)?;
+                let (trait_, dyn_ty, adjusted_recv) =
+                    if let ty::Dynamic(data, _, ty::DynStar) = receiver_place.layout.ty.kind() {
+                        let recv = self.unpack_dyn_star(&receiver_place, data)?;
 
-                    (data.principal(), recv.layout.ty, recv.ptr())
-                } else {
-                    // Doesn't have to be a `dyn Trait`, but the unsized tail must be `dyn Trait`.
-                    // (For that reason we also cannot use `unpack_dyn_trait`.)
-                    let receiver_tail =
-                        self.tcx.struct_tail_for_codegen(receiver_place.layout.ty, self.param_env);
-                    let ty::Dynamic(receiver_trait, _, ty::Dyn) = receiver_tail.kind() else {
-                        span_bug!(
-                            self.cur_span(),
-                            "dynamic call on non-`dyn` type {}",
-                            receiver_tail
-                        )
+                        (data.principal(), recv.layout.ty, recv.ptr())
+                    } else {
+                        // Doesn't have to be a `dyn Trait`, but the unsized tail must be `dyn Trait`.
+                        // (For that reason we also cannot use `unpack_dyn_trait`.)
+                        let receiver_tail = self
+                            .tcx
+                            .struct_tail_for_codegen(receiver_place.layout.ty, self.typing_env());
+                        let ty::Dynamic(receiver_trait, _, ty::Dyn) = receiver_tail.kind() else {
+                            span_bug!(
+                                self.cur_span(),
+                                "dynamic call on non-`dyn` type {}",
+                                receiver_tail
+                            )
+                        };
+                        assert!(receiver_place.layout.is_unsized());
+
+                        // Get the required information from the vtable.
+                        let vptr = receiver_place.meta().unwrap_meta().to_pointer(self)?;
+                        let dyn_ty = self.get_ptr_vtable_ty(vptr, Some(receiver_trait))?;
+
+                        // It might be surprising that we use a pointer as the receiver even if this
+                        // is a by-val case; this works because by-val passing of an unsized `dyn
+                        // Trait` to a function is actually desugared to a pointer.
+                        (receiver_trait.principal(), dyn_ty, receiver_place.ptr())
                     };
-                    assert!(receiver_place.layout.is_unsized());
-
-                    // Get the required information from the vtable.
-                    let vptr = receiver_place.meta().unwrap_meta().to_pointer(self)?;
-                    let dyn_ty = self.get_ptr_vtable_ty(vptr, Some(receiver_trait))?;
-
-                    // It might be surprising that we use a pointer as the receiver even if this
-                    // is a by-val case; this works because by-val passing of an unsized `dyn
-                    // Trait` to a function is actually desugared to a pointer.
-                    (receiver_trait.principal(), dyn_ty, receiver_place.ptr())
-                };
 
                 // Now determine the actual method to call. Usually we use the easy way of just
                 // looking up the method at index `idx`.
@@ -704,7 +704,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
                     let concrete_method = Instance::expect_resolve_for_vtable(
                         tcx,
-                        self.param_env,
+                        self.typing_env(),
                         def_id,
                         instance.args.rebase_onto(tcx, trait_def_id, concrete_trait_ref.args),
                         self.cur_span(),

compiler/rustc_const_eval/src/interpret/cast.rs

@@ -83,7 +83,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                     ty::FnDef(def_id, args) => {
                         let instance = ty::Instance::resolve_for_fn_ptr(
                             *self.tcx,
-                            self.param_env,
+                            self.typing_env(),
                             def_id,
                             args,
                         )
@@ -384,7 +384,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
     ) -> InterpResult<'tcx> {
         // A<Struct> -> A<Trait> conversion
         let (src_pointee_ty, dest_pointee_ty) =
-            self.tcx.struct_lockstep_tails_for_codegen(source_ty, cast_ty, self.param_env);
+            self.tcx.struct_lockstep_tails_for_codegen(source_ty, cast_ty, self.typing_env());
 
         match (src_pointee_ty.kind(), dest_pointee_ty.kind()) {
             (&ty::Array(_, length), &ty::Slice(_)) => {

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -10,9 +10,7 @@ use rustc_middle::query::TyCtxtAt;
 use rustc_middle::ty::layout::{
     self, FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout,
 };
-use rustc_middle::ty::{
-    self, GenericArgsRef, ParamEnv, Ty, TyCtxt, TypeFoldable, TypingMode, Variance,
-};
+use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeFoldable, TypingEnv, Variance};
 use rustc_middle::{mir, span_bug};
 use rustc_session::Limit;
 use rustc_span::Span;
@@ -65,12 +63,12 @@ where
     }
 }
 
-impl<'tcx, M> layout::HasParamEnv<'tcx> for InterpCx<'tcx, M>
+impl<'tcx, M> layout::HasTypingEnv<'tcx> for InterpCx<'tcx, M>
 where
     M: Machine<'tcx>,
 {
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        self.param_env
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        self.typing_env()
     }
 }
 
@@ -116,8 +114,7 @@ impl<'tcx, M: Machine<'tcx>> FnAbiOfHelpers<'tcx> for InterpCx<'tcx, M> {
 /// This test should be symmetric, as it is primarily about layout compatibility.
 pub(super) fn mir_assign_valid_types<'tcx>(
     tcx: TyCtxt<'tcx>,
-    typing_mode: TypingMode<'tcx>,
-    param_env: ParamEnv<'tcx>,
+    typing_env: TypingEnv<'tcx>,
     src: TyAndLayout<'tcx>,
     dest: TyAndLayout<'tcx>,
 ) -> bool {
@@ -125,7 +122,7 @@ pub(super) fn mir_assign_valid_types<'tcx>(
     // all normal lifetimes are erased, higher-ranked types with their
     // late-bound lifetimes are still around and can lead to type
     // differences.
-    if util::relate_types(tcx, typing_mode, param_env, Variance::Covariant, src.ty, dest.ty) {
+    if util::relate_types(tcx, typing_env, Variance::Covariant, src.ty, dest.ty) {
         // Make sure the layout is equal, too -- just to be safe. Miri really
         // needs layout equality. For performance reason we skip this check when
         // the types are equal. Equal types *can* have different layouts when
@@ -145,8 +142,7 @@ pub(super) fn mir_assign_valid_types<'tcx>(
 #[cfg_attr(not(debug_assertions), inline(always))]
 pub(super) fn from_known_layout<'tcx>(
     tcx: TyCtxtAt<'tcx>,
-    typing_mode: TypingMode<'tcx>,
-    param_env: ParamEnv<'tcx>,
+    typing_env: TypingEnv<'tcx>,
     known_layout: Option<TyAndLayout<'tcx>>,
     compute: impl FnOnce() -> InterpResult<'tcx, TyAndLayout<'tcx>>,
 ) -> InterpResult<'tcx, TyAndLayout<'tcx>> {
@@ -155,13 +151,7 @@ pub(super) fn from_known_layout<'tcx>(
         Some(known_layout) => {
             if cfg!(debug_assertions) {
                 let check_layout = compute()?;
-                if !mir_assign_valid_types(
-                    tcx.tcx,
-                    typing_mode,
-                    param_env,
-                    check_layout,
-                    known_layout,
-                ) {
+                if !mir_assign_valid_types(tcx.tcx, typing_env, check_layout, known_layout) {
                     span_bug!(
                         tcx.span,
                         "expected type differs from actual type.\nexpected: {}\nactual: {}",
@@ -211,9 +201,11 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         }
     }
 
-    pub fn typing_mode(&self) -> TypingMode<'tcx> {
+    /// During CTFE we're always in `PostAnalysis` mode.
+    #[inline(always)]
+    pub fn typing_env(&self) -> ty::TypingEnv<'tcx> {
         debug_assert_eq!(self.param_env.reveal(), Reveal::All);
-        TypingMode::PostAnalysis
+        ty::TypingEnv { typing_mode: ty::TypingMode::PostAnalysis, param_env: self.param_env }
     }
 
     /// Returns the span of the currently executed statement/terminator.
@@ -304,13 +296,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             .instance
             .try_instantiate_mir_and_normalize_erasing_regions(
                 *self.tcx,
-                self.param_env,
+                self.typing_env(),
                 ty::EarlyBinder::bind(value),
             )
             .map_err(|_| ErrorHandled::TooGeneric(self.cur_span()))
     }
 
-    /// The `args` are assumed to already be in our interpreter "universe" (param_env).
+    /// The `args` are assumed to already be in our interpreter "universe".
     pub(super) fn resolve(
         &self,
         def: DefId,
@@ -319,7 +311,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         trace!("resolve: {:?}, {:#?}", def, args);
         trace!("param_env: {:#?}", self.param_env);
         trace!("args: {:#?}", args);
-        match ty::Instance::try_resolve(*self.tcx, self.param_env, def, args) {
+        match ty::Instance::try_resolve(*self.tcx, self.typing_env(), def, args) {
             Ok(Some(instance)) => interp_ok(instance),
             Ok(None) => throw_inval!(TooGeneric),
 
@@ -328,7 +320,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         }
     }
 
-    /// Check if the two things are equal in the current param_env, using an infctx to get proper
+    /// Check if the two things are equal in the current param_env, using an infcx to get proper
     /// equality checks.
     #[instrument(level = "trace", skip(self), ret)]
     pub(super) fn eq_in_param_env<T>(&self, a: T, b: T) -> bool
@@ -340,14 +332,14 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             return true;
         }
         // Slow path: spin up an inference context to check if these traits are sufficiently equal.
-        let infcx = self.tcx.infer_ctxt().build(self.typing_mode());
+        let (infcx, param_env) = self.tcx.infer_ctxt().build_with_typing_env(self.typing_env());
         let ocx = ObligationCtxt::new(&infcx);
         let cause = ObligationCause::dummy_with_span(self.cur_span());
         // equate the two trait refs after normalization
-        let a = ocx.normalize(&cause, self.param_env, a);
-        let b = ocx.normalize(&cause, self.param_env, b);
+        let a = ocx.normalize(&cause, param_env, a);
+        let b = ocx.normalize(&cause, param_env, b);
 
-        if let Err(terr) = ocx.eq(&cause, self.param_env, a, b) {
+        if let Err(terr) = ocx.eq(&cause, param_env, a, b) {
             trace!(?terr);
             return false;
         }
@@ -572,7 +564,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         let val = if self.tcx.is_static(gid.instance.def_id()) {
             let alloc_id = self.tcx.reserve_and_set_static_alloc(gid.instance.def_id());
 
-            let ty = instance.ty(self.tcx.tcx, self.param_env);
+            let ty = instance.ty(self.tcx.tcx, self.typing_env());
             mir::ConstAlloc { alloc_id, ty }
         } else {
             self.ctfe_query(|tcx| tcx.eval_to_allocation_raw(self.param_env.and(gid)))?
@@ -587,7 +579,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         layout: Option<TyAndLayout<'tcx>>,
     ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> {
         M::eval_mir_constant(self, *val, span, layout, |ecx, val, span, layout| {
-            let const_val = val.eval(*ecx.tcx, ecx.param_env, span).map_err(|err| {
+            let const_val = val.eval(*ecx.tcx, ecx.typing_env(), span).map_err(|err| {
                 if M::ALL_CONSTS_ARE_PRECHECKED {
                     match err {
                         ErrorHandled::TooGeneric(..) => {},

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -40,6 +40,7 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>(
 ) -> InterpResult<'tcx, ConstValue<'tcx>> {
     let tp_ty = args.type_at(0);
     let name = tcx.item_name(def_id);
+    let typing_env = ty::TypingEnv { typing_mode: ty::TypingMode::PostAnalysis, param_env };
     interp_ok(match name {
         sym::type_name => {
             ensure_monomorphic_enough(tcx, tp_ty)?;
@@ -48,11 +49,13 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>(
         }
         sym::needs_drop => {
             ensure_monomorphic_enough(tcx, tp_ty)?;
-            ConstValue::from_bool(tp_ty.needs_drop(tcx, param_env))
+            ConstValue::from_bool(tp_ty.needs_drop(tcx, typing_env))
         }
         sym::pref_align_of => {
             // Correctly handles non-monomorphic calls, so there is no need for ensure_monomorphic_enough.
-            let layout = tcx.layout_of(param_env.and(tp_ty)).map_err(|e| err_inval!(Layout(*e)))?;
+            let layout = tcx
+                .layout_of(typing_env.as_query_input(tp_ty))
+                .map_err(|e| err_inval!(Layout(*e)))?;
             ConstValue::from_target_usize(layout.align.pref.bytes(), &tcx)
         }
         sym::type_id => {
@@ -355,7 +358,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
                 let should_panic = !self
                     .tcx
-                    .check_validity_requirement((requirement, self.param_env.and(ty)))
+                    .check_validity_requirement((requirement, self.typing_env().as_query_input(ty)))
                     .map_err(|_| err_inval!(TooGeneric))?;
 
                 if should_panic {

compiler/rustc_const_eval/src/interpret/memory.rs

@@ -859,7 +859,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
         // # Global allocations
         if let Some(global_alloc) = self.tcx.try_get_global_alloc(id) {
-            let (size, align) = global_alloc.size_and_align(*self.tcx, self.param_env);
+            let (size, align) = global_alloc.size_and_align(*self.tcx, self.typing_env());
             let mutbl = global_alloc.mutability(*self.tcx, self.param_env);
             let kind = match global_alloc {
                 GlobalAlloc::Static { .. } | GlobalAlloc::Memory { .. } => AllocKind::LiveData,

compiler/rustc_const_eval/src/interpret/operand.rs

@@ -8,7 +8,7 @@ use rustc_abi as abi;
 use rustc_abi::{BackendRepr, HasDataLayout, Size};
 use rustc_hir::def::Namespace;
 use rustc_middle::mir::interpret::ScalarSizeMismatch;
-use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutOf, TyAndLayout};
+use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv, LayoutOf, TyAndLayout};
 use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter};
 use rustc_middle::ty::{ConstInt, ScalarInt, Ty, TyCtxt};
 use rustc_middle::{bug, mir, span_bug, ty};
@@ -297,21 +297,25 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
 
     #[inline]
     pub fn from_bool(b: bool, tcx: TyCtxt<'tcx>) -> Self {
-        let layout = tcx.layout_of(ty::ParamEnv::reveal_all().and(tcx.types.bool)).unwrap();
+        let layout = tcx
+            .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(tcx.types.bool))
+            .unwrap();
         Self::from_scalar(Scalar::from_bool(b), layout)
     }
 
     #[inline]
     pub fn from_ordering(c: std::cmp::Ordering, tcx: TyCtxt<'tcx>) -> Self {
         let ty = tcx.ty_ordering_enum(None);
-        let layout = tcx.layout_of(ty::ParamEnv::reveal_all().and(ty)).unwrap();
+        let layout =
+            tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty)).unwrap();
         Self::from_scalar(Scalar::from_i8(c as i8), layout)
     }
 
     pub fn from_pair(a: Self, b: Self, tcx: TyCtxt<'tcx>) -> Self {
         let layout = tcx
             .layout_of(
-                ty::ParamEnv::reveal_all().and(Ty::new_tup(tcx, &[a.layout.ty, b.layout.ty])),
+                ty::TypingEnv::fully_monomorphized()
+                    .as_query_input(Ty::new_tup(tcx, &[a.layout.ty, b.layout.ty])),
             )
             .unwrap();
         Self::from_scalar_pair(a.to_scalar(), b.to_scalar(), layout)
@@ -341,7 +345,7 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> {
 
     #[inline]
     #[cfg_attr(debug_assertions, track_caller)] // only in debug builds due to perf (see #98980)
-    pub fn to_pair(self, cx: &(impl HasTyCtxt<'tcx> + HasParamEnv<'tcx>)) -> (Self, Self) {
+    pub fn to_pair(self, cx: &(impl HasTyCtxt<'tcx> + HasTypingEnv<'tcx>)) -> (Self, Self) {
         let layout = self.layout;
         let (val0, val1) = self.to_scalar_pair();
         (
@@ -773,8 +777,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 )?;
             if !mir_assign_valid_types(
                 *self.tcx,
-                self.typing_mode(),
-                self.param_env,
+                self.typing_env(),
                 self.layout_of(normalized_place_ty)?,
                 op.layout,
             ) {
@@ -833,9 +836,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             })
         };
         let layout =
-            from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || {
-                self.layout_of(ty).into()
-            })?;
+            from_known_layout(self.tcx, self.typing_env(), layout, || self.layout_of(ty).into())?;
         let imm = match val_val {
             mir::ConstValue::Indirect { alloc_id, offset } => {
                 // This is const data, no mutation allowed.

compiler/rustc_const_eval/src/interpret/operator.rs

@@ -533,7 +533,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             }
             OffsetOf(fields) => {
                 let val =
-                    self.tcx.offset_of_subfield(self.param_env, layout, fields.iter()).bytes();
+                    self.tcx.offset_of_subfield(self.typing_env(), layout, fields.iter()).bytes();
                 ImmTy::from_uint(val, usize_layout())
             }
             UbChecks => ImmTy::from_bool(M::ub_checks(self)?, *self.tcx),

compiler/rustc_const_eval/src/interpret/place.rs

@@ -540,8 +540,7 @@ where
                 )?;
             if !mir_assign_valid_types(
                 *self.tcx,
-                self.typing_mode(),
-                self.param_env,
+                self.typing_env(),
                 self.layout_of(normalized_place_ty)?,
                 place.layout,
             ) {
@@ -871,13 +870,8 @@ where
     ) -> InterpResult<'tcx> {
         // We do NOT compare the types for equality, because well-typed code can
         // actually "transmute" `&mut T` to `&T` in an assignment without a cast.
-        let layout_compat = mir_assign_valid_types(
-            *self.tcx,
-            self.typing_mode(),
-            self.param_env,
-            src.layout(),
-            dest.layout(),
-        );
+        let layout_compat =
+            mir_assign_valid_types(*self.tcx, self.typing_env(), src.layout(), dest.layout());
         if !allow_transmute && !layout_compat {
             span_bug!(
                 self.cur_span(),

compiler/rustc_const_eval/src/interpret/stack.rs

@@ -379,7 +379,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         for &const_ in body.required_consts() {
             let c =
                 self.instantiate_from_current_frame_and_normalize_erasing_regions(const_.const_)?;
-            c.eval(*self.tcx, self.param_env, const_.span).map_err(|err| {
+            c.eval(*self.tcx, self.typing_env(), const_.span).map_err(|err| {
                 err.emit_note(*self.tcx);
                 err
             })?;
@@ -596,13 +596,12 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             return interp_ok(layout);
         }
 
-        let layout =
-            from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || {
-                let local_ty = frame.body.local_decls[local].ty;
-                let local_ty =
-                    self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?;
-                self.layout_of(local_ty).into()
-            })?;
+        let layout = from_known_layout(self.tcx, self.typing_env(), layout, || {
+            let local_ty = frame.body.local_decls[local].ty;
+            let local_ty =
+                self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?;
+            self.layout_of(local_ty).into()
+        })?;
 
         // Layouts of locals are requested a lot, so we cache them.
         state.layout.set(Some(layout));

compiler/rustc_const_eval/src/interpret/step.rs

@@ -418,7 +418,8 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
             .collect::<InterpResult<'tcx, Vec<_>>>()?;
 
         let fn_sig_binder = func.layout.ty.fn_sig(*self.tcx);
-        let fn_sig = self.tcx.normalize_erasing_late_bound_regions(self.param_env, fn_sig_binder);
+        let fn_sig =
+            self.tcx.normalize_erasing_late_bound_regions(self.typing_env(), fn_sig_binder);
         let extra_args = &args[fn_sig.inputs().len()..];
         let extra_args =
             self.tcx.mk_type_list_from_iter(extra_args.iter().map(|arg| arg.layout().ty));

compiler/rustc_const_eval/src/interpret/validity.rs

@@ -448,7 +448,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> {
         meta: MemPlaceMeta<M::Provenance>,
         pointee: TyAndLayout<'tcx>,
     ) -> InterpResult<'tcx> {
-        let tail = self.ecx.tcx.struct_tail_for_codegen(pointee.ty, self.ecx.param_env);
+        let tail = self.ecx.tcx.struct_tail_for_codegen(pointee.ty, self.ecx.typing_env());
         match tail.kind() {
             ty::Dynamic(data, _, ty::Dyn) => {
                 let vtable = meta.unwrap_meta().to_pointer(self.ecx)?;
@@ -568,7 +568,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> {
                         throw_validation_failure!(self.path, DanglingPtrUseAfterFree { ptr_kind });
                     };
                     let (size, _align) =
-                        global_alloc.size_and_align(*self.ecx.tcx, self.ecx.param_env);
+                        global_alloc.size_and_align(*self.ecx.tcx, self.ecx.typing_env());
 
                     if let GlobalAlloc::Static(did) = global_alloc {
                         let DefKind::Static { nested, .. } = self.ecx.tcx.def_kind(did) else {
@@ -955,7 +955,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> {
     ) -> Cow<'e, RangeSet> {
         assert!(layout.ty.is_union());
         assert!(layout.is_sized(), "there are no unsized unions");
-        let layout_cx = LayoutCx::new(*ecx.tcx, ecx.param_env);
+        let layout_cx = LayoutCx::new(*ecx.tcx, ecx.typing_env());
         return M::cached_union_data_range(ecx, layout.ty, || {
             let mut out = RangeSet(Vec::new());
             union_data_range_uncached(&layout_cx, layout, Size::ZERO, &mut out);

compiler/rustc_const_eval/src/lib.rs

@@ -47,7 +47,7 @@ pub fn provide(providers: &mut Providers) {
     providers.hooks.try_destructure_mir_constant_for_user_output =
         const_eval::try_destructure_mir_constant_for_user_output;
     providers.valtree_to_const_val = |tcx, (ty, valtree)| {
-        const_eval::valtree_to_const_value(tcx, ty::ParamEnv::empty().and(ty), valtree)
+        const_eval::valtree_to_const_value(tcx, ty::ParamEnv::reveal_all().and(ty), valtree)
     };
     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/alignment.rs

@@ -9,7 +9,7 @@ use tracing::debug;
 pub fn is_disaligned<'tcx, L>(
     tcx: TyCtxt<'tcx>,
     local_decls: &L,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     place: Place<'tcx>,
 ) -> bool
 where
@@ -22,8 +22,8 @@ where
     };
 
     let ty = place.ty(local_decls, tcx).ty;
-    let unsized_tail = || tcx.struct_tail_for_codegen(ty, param_env);
-    match tcx.layout_of(param_env.and(ty)) {
+    let unsized_tail = || tcx.struct_tail_for_codegen(ty, typing_env);
+    match tcx.layout_of(typing_env.as_query_input(ty)) {
         Ok(layout)
             if layout.align.abi <= pack
                 && (layout.is_sized()

compiler/rustc_const_eval/src/util/check_validity_requirement.rs

@@ -3,7 +3,7 @@ use rustc_middle::bug;
 use rustc_middle::ty::layout::{
     HasTyCtxt, LayoutCx, LayoutError, LayoutOf, TyAndLayout, ValidityRequirement,
 };
-use rustc_middle::ty::{ParamEnvAnd, Ty, TyCtxt};
+use rustc_middle::ty::{PseudoCanonicalInput, Ty, TyCtxt};
 
 use crate::const_eval::{CanAccessMutGlobal, CheckAlignment, CompileTimeMachine};
 use crate::interpret::{InterpCx, MemoryKind};
@@ -23,16 +23,16 @@ use crate::interpret::{InterpCx, MemoryKind};
 pub fn check_validity_requirement<'tcx>(
     tcx: TyCtxt<'tcx>,
     kind: ValidityRequirement,
-    param_env_and_ty: ParamEnvAnd<'tcx, Ty<'tcx>>,
+    input: PseudoCanonicalInput<'tcx, Ty<'tcx>>,
 ) -> Result<bool, &'tcx LayoutError<'tcx>> {
-    let layout = tcx.layout_of(param_env_and_ty)?;
+    let layout = tcx.layout_of(input)?;
 
     // There is nothing strict or lax about inhabitedness.
     if kind == ValidityRequirement::Inhabited {
         return Ok(!layout.is_uninhabited());
     }
 
-    let layout_cx = LayoutCx::new(tcx, param_env_and_ty.param_env);
+    let layout_cx = LayoutCx::new(tcx, input.typing_env);
     if kind == ValidityRequirement::Uninit || tcx.sess.opts.unstable_opts.strict_init_checks {
         check_validity_requirement_strict(layout, &layout_cx, kind)
     } else {
@@ -49,7 +49,7 @@ fn check_validity_requirement_strict<'tcx>(
 ) -> Result<bool, &'tcx LayoutError<'tcx>> {
     let machine = CompileTimeMachine::new(CanAccessMutGlobal::No, CheckAlignment::Error);
 
-    let mut cx = InterpCx::new(cx.tcx(), rustc_span::DUMMY_SP, cx.param_env, machine);
+    let mut cx = InterpCx::new(cx.tcx(), rustc_span::DUMMY_SP, cx.typing_env.param_env, machine);
 
     let allocated = cx
         .allocate(ty, MemoryKind::Machine(crate::const_eval::MemoryKind::Heap))

compiler/rustc_const_eval/src/util/compare_types.rs

@@ -5,18 +5,17 @@
 
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::traits::ObligationCause;
-use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, TypingMode, Variance};
+use rustc_middle::ty::{Ty, TyCtxt, TypingEnv, Variance};
 use rustc_trait_selection::traits::ObligationCtxt;
 
 /// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`.
 pub fn sub_types<'tcx>(
     tcx: TyCtxt<'tcx>,
-    typing_mode: TypingMode<'tcx>,
-    param_env: ParamEnv<'tcx>,
+    typing_env: TypingEnv<'tcx>,
     src: Ty<'tcx>,
     dest: Ty<'tcx>,
 ) -> bool {
-    relate_types(tcx, typing_mode, param_env, Variance::Covariant, src, dest)
+    relate_types(tcx, typing_env, Variance::Covariant, src, dest)
 }
 
 /// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`.
@@ -26,8 +25,7 @@ pub fn sub_types<'tcx>(
 /// because we want to check for type equality.
 pub fn relate_types<'tcx>(
     tcx: TyCtxt<'tcx>,
-    typing_mode: TypingMode<'tcx>,
-    param_env: ParamEnv<'tcx>,
+    typing_env: TypingEnv<'tcx>,
     variance: Variance,
     src: Ty<'tcx>,
     dest: Ty<'tcx>,
@@ -36,8 +34,7 @@ pub fn relate_types<'tcx>(
         return true;
     }
 
-    let mut builder = tcx.infer_ctxt().ignoring_regions();
-    let infcx = builder.build(typing_mode);
+    let (infcx, param_env) = tcx.infer_ctxt().ignoring_regions().build_with_typing_env(typing_env);
     let ocx = ObligationCtxt::new(&infcx);
     let cause = ObligationCause::dummy();
     let src = ocx.normalize(&cause, param_env, src);

compiler/rustc_hir_analysis/src/check/check.rs

@@ -21,8 +21,7 @@ use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
 use rustc_middle::ty::util::{Discr, InspectCoroutineFields, IntTypeExt};
 use rustc_middle::ty::{
-    AdtDef, GenericArgKind, ParamEnv, RegionKind, TypeSuperVisitable, TypeVisitable,
-    TypeVisitableExt,
+    AdtDef, GenericArgKind, RegionKind, TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
 };
 use rustc_session::lint::builtin::UNINHABITED_STATIC;
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
@@ -114,15 +113,15 @@ fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> b
             }
         }
 
-        let param_env = tcx.param_env(item_def_id);
+        let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id);
         for field in &def.non_enum_variant().fields {
-            let Ok(field_ty) = tcx.try_normalize_erasing_regions(param_env, field.ty(tcx, args))
+            let Ok(field_ty) = tcx.try_normalize_erasing_regions(typing_env, field.ty(tcx, args))
             else {
                 tcx.dcx().span_delayed_bug(span, "could not normalize field type");
                 continue;
             };
 
-            if !allowed_union_field(field_ty, tcx, param_env) {
+            if !allowed_union_field(field_ty, tcx, typing_env.param_env) {
                 let (field_span, ty_span) = match tcx.hir().get_if_local(field.did) {
                     // We are currently checking the type this field came from, so it must be local.
                     Some(Node::Field(field)) => (field.span, field.ty.span),
@@ -137,7 +136,7 @@ fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> b
                     note: (),
                 });
                 return false;
-            } else if field_ty.needs_drop(tcx, param_env) {
+            } else if field_ty.needs_drop(tcx, typing_env) {
                 // This should never happen. But we can get here e.g. in case of name resolution errors.
                 tcx.dcx()
                     .span_delayed_bug(span, "we should never accept maybe-dropping union fields");
@@ -158,7 +157,7 @@ fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     // reason to allow any statics to be uninhabited.
     let ty = tcx.type_of(def_id).instantiate_identity();
     let span = tcx.def_span(def_id);
-    let layout = match tcx.layout_of(ParamEnv::reveal_all().and(ty)) {
+    let layout = match tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty)) {
         Ok(l) => l,
         // Foreign statics that overflow their allowed size should emit an error
         Err(LayoutError::SizeOverflow(_))
@@ -237,7 +236,10 @@ pub(super) fn check_opaque_for_cycles<'tcx>(
 
         // And also look for cycle errors in the layout of coroutines.
         if let Err(&LayoutError::Cycle(guar)) =
-            tcx.layout_of(tcx.param_env(def_id).and(Ty::new_opaque(tcx, def_id.to_def_id(), args)))
+            tcx.layout_of(
+                ty::TypingEnv::post_analysis(tcx, def_id.to_def_id())
+                    .as_query_input(Ty::new_opaque(tcx, def_id.to_def_id(), args)),
+            )
         {
             return Err(guar);
         }
@@ -1307,8 +1309,8 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>)
     // "known" respecting #[non_exhaustive] attributes.
     let field_infos = adt.all_fields().map(|field| {
         let ty = field.ty(tcx, GenericArgs::identity_for_item(tcx, field.did));
-        let param_env = tcx.param_env(field.did);
-        let layout = tcx.layout_of(param_env.and(ty));
+        let typing_env = ty::TypingEnv::non_body_analysis(tcx, field.did);
+        let layout = tcx.layout_of(typing_env.as_query_input(ty));
         // We are currently checking the type this field came from, so it must be local
         let span = tcx.hir().span_if_local(field.did).unwrap();
         let trivial = layout.is_ok_and(|layout| layout.is_1zst());

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -1126,7 +1126,7 @@ fn check_type_defn<'tcx>(
                     let ty = tcx.type_of(variant.tail().did).instantiate_identity();
                     let ty = tcx.erase_regions(ty);
                     assert!(!ty.has_infer());
-                    ty.needs_drop(tcx, tcx.param_env(item.owner_id))
+                    ty.needs_drop(tcx, wfcx.infcx.typing_env(wfcx.param_env))
                 }
             };
             // All fields (except for possibly the last) should be sized.
@@ -1281,7 +1281,8 @@ fn check_item_type(
             UnsizedHandling::Forbid => true,
             UnsizedHandling::Allow => false,
             UnsizedHandling::AllowIfForeignTail => {
-                let tail = tcx.struct_tail_for_codegen(item_ty, wfcx.param_env);
+                let tail =
+                    tcx.struct_tail_for_codegen(item_ty, wfcx.infcx.typing_env(wfcx.param_env));
                 !matches!(tail.kind(), ty::Foreign(_))
             }
         };

compiler/rustc_hir_analysis/src/coherence/builtin.rs

@@ -259,7 +259,9 @@ fn visit_implementation_of_dispatch_from_dyn(checker: &Checker<'_>) -> Result<()
                     let ty_a = field.ty(tcx, args_a);
                     let ty_b = field.ty(tcx, args_b);
 
-                    if let Ok(layout) = tcx.layout_of(param_env.and(ty_a)) {
+                    if let Ok(layout) =
+                        tcx.layout_of(infcx.typing_env(param_env).as_query_input(ty_a))
+                    {
                         if layout.is_1zst() {
                             // ignore 1-ZST fields
                             return false;

compiler/rustc_hir_analysis/src/hir_ty_lowering/cmse.rs

@@ -3,7 +3,7 @@ use rustc_errors::{DiagCtxtHandle, E0781, struct_span_code_err};
 use rustc_hir::{self as hir, HirId};
 use rustc_middle::bug;
 use rustc_middle::ty::layout::LayoutError;
-use rustc_middle::ty::{self, ParamEnv, TyCtxt};
+use rustc_middle::ty::{self, TyCtxt};
 
 use crate::errors;
 
@@ -130,7 +130,7 @@ fn is_valid_cmse_inputs<'tcx>(
     let fn_sig = tcx.instantiate_bound_regions_with_erased(fn_sig);
 
     for (index, ty) in fn_sig.inputs().iter().enumerate() {
-        let layout = tcx.layout_of(ParamEnv::reveal_all().and(*ty))?;
+        let layout = tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(*ty))?;
 
         let align = layout.layout.align().abi.bytes();
         let size = layout.layout.size().bytes();
@@ -158,8 +158,10 @@ fn is_valid_cmse_output<'tcx>(
     // this type is only used for layout computation, which does not rely on regions
     let fn_sig = tcx.instantiate_bound_regions_with_erased(fn_sig);
 
+    let typing_env = ty::TypingEnv::fully_monomorphized();
+
     let mut ret_ty = fn_sig.output();
-    let layout = tcx.layout_of(ParamEnv::reveal_all().and(ret_ty))?;
+    let layout = tcx.layout_of(typing_env.as_query_input(ret_ty))?;
     let size = layout.layout.size().bytes();
 
     if size <= 4 {
@@ -182,7 +184,7 @@ fn is_valid_cmse_output<'tcx>(
         for variant_def in adt_def.variants() {
             for field_def in variant_def.fields.iter() {
                 let ty = field_def.ty(tcx, args);
-                let layout = tcx.layout_of(ParamEnv::reveal_all().and(ty))?;
+                let layout = tcx.layout_of(typing_env.as_query_input(ty))?;
 
                 if !layout.layout.is_1zst() {
                     ret_ty = ty;

compiler/rustc_hir_typeck/src/expr.rs

@@ -2357,8 +2357,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // Only assoc fns that return `Self`
                     let fn_sig = self.tcx.fn_sig(item.def_id).skip_binder();
                     let ret_ty = fn_sig.output();
-                    let ret_ty =
-                        self.tcx.normalize_erasing_late_bound_regions(self.param_env, ret_ty);
+                    let ret_ty = self.tcx.normalize_erasing_late_bound_regions(
+                        self.typing_env(self.param_env),
+                        ret_ty,
+                    );
                     if !self.can_eq(self.param_env, ret_ty, adt_ty) {
                         return None;
                     }

compiler/rustc_hir_typeck/src/intrinsicck.rs

@@ -46,7 +46,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let span = tcx.hir().span(hir_id);
         let normalize = |ty| {
             let ty = self.resolve_vars_if_possible(ty);
-            self.tcx.normalize_erasing_regions(self.param_env, ty)
+            self.tcx.normalize_erasing_regions(self.typing_env(self.param_env), ty)
         };
         let from = normalize(from);
         let to = normalize(to);
@@ -62,7 +62,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             return;
         }
 
-        let skel = |ty| SizeSkeleton::compute(ty, tcx, self.param_env);
+        let skel = |ty| SizeSkeleton::compute(ty, tcx, self.typing_env(self.param_env));
         let sk_from = skel(from);
         let sk_to = skel(to);
         trace!(?sk_from, ?sk_to);

compiler/rustc_hir_typeck/src/upvar.rs

@@ -1257,7 +1257,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> Option<FxIndexSet<UpvarMigrationInfo>> {
         let ty = self.resolve_vars_if_possible(self.node_ty(var_hir_id));
 
-        if !ty.has_significant_drop(self.tcx, self.tcx.param_env(closure_def_id)) {
+        // FIXME(#132279): Using `non_body_analysis` here feels wrong.
+        if !ty.has_significant_drop(
+            self.tcx,
+            ty::TypingEnv::non_body_analysis(self.tcx, closure_def_id),
+        ) {
             debug!("does not have significant drop");
             return None;
         }
@@ -1535,8 +1539,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         base_path_ty: Ty<'tcx>,
         captured_by_move_projs: Vec<&[Projection<'tcx>]>,
     ) -> bool {
-        let needs_drop =
-            |ty: Ty<'tcx>| ty.has_significant_drop(self.tcx, self.tcx.param_env(closure_def_id));
+        // FIXME(#132279): Using `non_body_analysis` here feels wrong.
+        let needs_drop = |ty: Ty<'tcx>| {
+            ty.has_significant_drop(
+                self.tcx,
+                ty::TypingEnv::non_body_analysis(self.tcx, closure_def_id),
+            )
+        };
 
         let is_drop_defined_for_ty = |ty: Ty<'tcx>| {
             let drop_trait = self.tcx.require_lang_item(hir::LangItem::Drop, Some(closure_span));

compiler/rustc_hir_typeck/src/writeback.rs

@@ -881,6 +881,8 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for EagerlyNormalizeConsts<'tcx> {
     }
 
     fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> {
-        self.tcx.try_normalize_erasing_regions(self.param_env, ct).unwrap_or(ct)
+        self.tcx
+            .try_normalize_erasing_regions(ty::TypingEnv::from_param_env(self.param_env), ct)
+            .unwrap_or(ct)
     }
 }

compiler/rustc_infer/src/infer/mod.rs

@@ -38,7 +38,8 @@ use rustc_middle::ty::fold::{
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, ConstVid, FloatVid, GenericArg, GenericArgKind, GenericArgs, GenericArgsRef,
-    GenericParamDefKind, InferConst, IntVid, Ty, TyCtxt, TyVid, TypingMode,
+    GenericParamDefKind, InferConst, IntVid, PseudoCanonicalInput, Ty, TyCtxt, TyVid,
+    TypeVisitable, TypingEnv, TypingMode,
 };
 use rustc_span::Span;
 use rustc_span::symbol::Symbol;
@@ -565,6 +566,13 @@ impl<'tcx> InferCtxtBuilder<'tcx> {
         (infcx, value, args)
     }
 
+    pub fn build_with_typing_env(
+        mut self,
+        TypingEnv { typing_mode, param_env }: TypingEnv<'tcx>,
+    ) -> (InferCtxt<'tcx>, ty::ParamEnv<'tcx>) {
+        (self.build(typing_mode), param_env)
+    }
+
     pub fn build(&mut self, typing_mode: TypingMode<'tcx>) -> InferCtxt<'tcx> {
         let InferCtxtBuilder { tcx, considering_regions, skip_leak_check, next_trait_solver } =
             *self;
@@ -1278,6 +1286,42 @@ impl<'tcx> InferCtxt<'tcx> {
         u
     }
 
+    /// Extract [`ty::TypingMode`] of this inference context to get a `TypingEnv`
+    /// which contains the necessary information to use the trait system without
+    /// using canonicalization or carrying this inference context around.
+    pub fn typing_env(&self, param_env: ty::ParamEnv<'tcx>) -> ty::TypingEnv<'tcx> {
+        let typing_mode = match self.typing_mode(param_env) {
+            ty::TypingMode::Coherence => ty::TypingMode::Coherence,
+            // FIXME(#132279): This erases the `defining_opaque_types` as it isn't possible
+            // to handle them without proper canonicalization. This means we may cause cycle
+            // errors and fail to reveal opaques while inside of bodies. We should rename this
+            // function and require explicit comments on all use-sites in the future.
+            ty::TypingMode::Analysis { defining_opaque_types: _ } => {
+                TypingMode::non_body_analysis()
+            }
+            ty::TypingMode::PostAnalysis => ty::TypingMode::PostAnalysis,
+        };
+        ty::TypingEnv { typing_mode, param_env }
+    }
+
+    /// Similar to [`Self::canonicalize_query`], except that it returns
+    /// a [`PseudoCanonicalInput`] and requires both the `value` and the
+    /// `param_env` to not contain any inference variables or placeholders.
+    pub fn pseudo_canonicalize_query<V>(
+        &self,
+        param_env: ty::ParamEnv<'tcx>,
+        value: V,
+    ) -> PseudoCanonicalInput<'tcx, V>
+    where
+        V: TypeVisitable<TyCtxt<'tcx>>,
+    {
+        debug_assert!(!value.has_infer());
+        debug_assert!(!value.has_placeholders());
+        debug_assert!(!param_env.has_infer());
+        debug_assert!(!param_env.has_placeholders());
+        self.typing_env(param_env).as_query_input(value)
+    }
+
     /// The returned function is used in a fast path. If it returns `true` the variable is
     /// unchanged, `false` indicates that the status is unknown.
     #[inline]

compiler/rustc_lint/src/builtin.rs

@@ -2485,7 +2485,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue {
             });
 
             // Check if this ADT has a constrained layout (like `NonNull` and friends).
-            if let Ok(layout) = cx.tcx.layout_of(cx.param_env.and(ty)) {
+            if let Ok(layout) = cx.tcx.layout_of(cx.typing_env().as_query_input(ty)) {
                 if let BackendRepr::Scalar(scalar) | BackendRepr::ScalarPair(scalar, _) =
                     &layout.backend_repr
                 {
@@ -2521,7 +2521,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue {
             ty: Ty<'tcx>,
             init: InitKind,
         ) -> Option<InitError> {
-            let ty = cx.tcx.try_normalize_erasing_regions(cx.param_env, ty).unwrap_or(ty);
+            let ty = cx.tcx.try_normalize_erasing_regions(cx.typing_env(), ty).unwrap_or(ty);
 
             use rustc_type_ir::TyKind::*;
             match ty.kind() {
@@ -2568,7 +2568,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue {
                         let definitely_inhabited = match variant
                             .inhabited_predicate(cx.tcx, *adt_def)
                             .instantiate(cx.tcx, args)
-                            .apply_any_module(cx.tcx, cx.param_env)
+                            .apply_any_module(cx.tcx, cx.typing_env())
                         {
                             // Entirely skip uninhabited variants.
                             Some(false) => return None,

compiler/rustc_lint/src/context.rs

@@ -19,7 +19,7 @@ use rustc_middle::bug;
 use rustc_middle::middle::privacy::EffectiveVisibilities;
 use rustc_middle::ty::layout::{LayoutError, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::print::{PrintError, PrintTraitRefExt as _, Printer, with_no_trimmed_paths};
-use rustc_middle::ty::{self, GenericArg, RegisteredTools, Ty, TyCtxt, TypingMode};
+use rustc_middle::ty::{self, GenericArg, RegisteredTools, Ty, TyCtxt, TypingEnv, TypingMode};
 use rustc_session::lint::{
     BuiltinLintDiag, FutureIncompatibleInfo, Level, Lint, LintBuffer, LintExpectationId, LintId,
 };
@@ -708,6 +708,10 @@ impl<'tcx> LateContext<'tcx> {
         TypingMode::non_body_analysis()
     }
 
+    pub fn typing_env(&self) -> TypingEnv<'tcx> {
+        TypingEnv { typing_mode: self.typing_mode(), param_env: self.param_env }
+    }
+
     /// Gets the type-checking results for the current body,
     /// or `None` if outside a body.
     pub fn maybe_typeck_results(&self) -> Option<&'tcx ty::TypeckResults<'tcx>> {
@@ -906,7 +910,7 @@ impl<'tcx> LateContext<'tcx> {
             .find_by_name_and_kind(tcx, Ident::from_str(name), ty::AssocKind::Type, trait_id)
             .and_then(|assoc| {
                 let proj = Ty::new_projection(tcx, assoc.def_id, [self_ty]);
-                tcx.try_normalize_erasing_regions(self.param_env, proj).ok()
+                tcx.try_normalize_erasing_regions(self.typing_env(), proj).ok()
             })
     }
 
@@ -1010,10 +1014,10 @@ impl<'tcx> ty::layout::HasTyCtxt<'tcx> for LateContext<'tcx> {
     }
 }
 
-impl<'tcx> ty::layout::HasParamEnv<'tcx> for LateContext<'tcx> {
+impl<'tcx> ty::layout::HasTypingEnv<'tcx> for LateContext<'tcx> {
     #[inline]
-    fn param_env(&self) -> ty::ParamEnv<'tcx> {
-        self.param_env
+    fn typing_env(&self) -> ty::TypingEnv<'tcx> {
+        self.typing_env()
     }
 }
 

compiler/rustc_lint/src/for_loops_over_fallibles.rs

@@ -166,7 +166,7 @@ fn suggest_question_mark<'tcx>(
     }
 
     let ty = args.type_at(0);
-    let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
+    let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(cx.typing_env());
     let ocx = ObligationCtxt::new(&infcx);
 
     let body_def_id = cx.tcx.hir().body_owner_def_id(body_id);
@@ -175,7 +175,7 @@ fn suggest_question_mark<'tcx>(
 
     ocx.register_bound(
         cause,
-        cx.param_env,
+        param_env,
         // Erase any region vids from the type, which may not be resolved
         infcx.tcx.erase_regions(ty),
         into_iterator_did,

compiler/rustc_lint/src/foreign_modules.rs

@@ -131,7 +131,7 @@ impl ClashingExternDeclarations {
         // Check that the declarations match.
         if !structurally_same_type(
             tcx,
-            tcx.param_env(this_fi.owner_id),
+            ty::TypingEnv::non_body_analysis(tcx, this_fi.owner_id),
             existing_decl_ty,
             this_decl_ty,
             types::CItemKind::Declaration,
@@ -205,18 +205,18 @@ fn get_relevant_span(tcx: TyCtxt<'_>, fi: hir::OwnerId) -> Span {
 /// with the same members (as the declarations shouldn't clash).
 fn structurally_same_type<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     a: Ty<'tcx>,
     b: Ty<'tcx>,
     ckind: types::CItemKind,
 ) -> bool {
     let mut seen_types = UnordSet::default();
-    let result = structurally_same_type_impl(&mut seen_types, tcx, param_env, a, b, ckind);
+    let result = structurally_same_type_impl(&mut seen_types, tcx, typing_env, a, b, ckind);
     if cfg!(debug_assertions) && result {
         // Sanity-check: must have same ABI, size and alignment.
         // `extern` blocks cannot be generic, so we'll always get a layout here.
-        let a_layout = tcx.layout_of(param_env.and(a)).unwrap();
-        let b_layout = tcx.layout_of(param_env.and(b)).unwrap();
+        let a_layout = tcx.layout_of(typing_env.as_query_input(a)).unwrap();
+        let b_layout = tcx.layout_of(typing_env.as_query_input(b)).unwrap();
         assert_eq!(a_layout.backend_repr, b_layout.backend_repr);
         assert_eq!(a_layout.size, b_layout.size);
         assert_eq!(a_layout.align, b_layout.align);
@@ -227,7 +227,7 @@ fn structurally_same_type<'tcx>(
 fn structurally_same_type_impl<'tcx>(
     seen_types: &mut UnordSet<(Ty<'tcx>, Ty<'tcx>)>,
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     a: Ty<'tcx>,
     b: Ty<'tcx>,
     ckind: types::CItemKind,
@@ -303,7 +303,7 @@ fn structurally_same_type_impl<'tcx>(
                             structurally_same_type_impl(
                                 seen_types,
                                 tcx,
-                                param_env,
+                                typing_env,
                                 tcx.type_of(a_did).instantiate(tcx, a_gen_args),
                                 tcx.type_of(b_did).instantiate(tcx, b_gen_args),
                                 ckind,
@@ -315,23 +315,23 @@ fn structurally_same_type_impl<'tcx>(
                     // For arrays, we also check the length.
                     a_len == b_len
                         && structurally_same_type_impl(
-                            seen_types, tcx, param_env, *a_ty, *b_ty, ckind,
+                            seen_types, tcx, typing_env, *a_ty, *b_ty, ckind,
                         )
                 }
                 (Slice(a_ty), Slice(b_ty)) => {
-                    structurally_same_type_impl(seen_types, tcx, param_env, *a_ty, *b_ty, ckind)
+                    structurally_same_type_impl(seen_types, tcx, typing_env, *a_ty, *b_ty, ckind)
                 }
                 (RawPtr(a_ty, a_mutbl), RawPtr(b_ty, b_mutbl)) => {
                     a_mutbl == b_mutbl
                         && structurally_same_type_impl(
-                            seen_types, tcx, param_env, *a_ty, *b_ty, ckind,
+                            seen_types, tcx, typing_env, *a_ty, *b_ty, ckind,
                         )
                 }
                 (Ref(_a_region, a_ty, a_mut), Ref(_b_region, b_ty, b_mut)) => {
                     // For structural sameness, we don't need the region to be same.
                     a_mut == b_mut
                         && structurally_same_type_impl(
-                            seen_types, tcx, param_env, *a_ty, *b_ty, ckind,
+                            seen_types, tcx, typing_env, *a_ty, *b_ty, ckind,
                         )
                 }
                 (FnDef(..), FnDef(..)) => {
@@ -346,12 +346,12 @@ fn structurally_same_type_impl<'tcx>(
                     (a_sig.abi, a_sig.safety, a_sig.c_variadic)
                         == (b_sig.abi, b_sig.safety, b_sig.c_variadic)
                         && a_sig.inputs().iter().eq_by(b_sig.inputs().iter(), |a, b| {
-                            structurally_same_type_impl(seen_types, tcx, param_env, *a, *b, ckind)
+                            structurally_same_type_impl(seen_types, tcx, typing_env, *a, *b, ckind)
                         })
                         && structurally_same_type_impl(
                             seen_types,
                             tcx,
-                            param_env,
+                            typing_env,
                             a_sig.output(),
                             b_sig.output(),
                             ckind,
@@ -379,14 +379,14 @@ fn structurally_same_type_impl<'tcx>(
                 // An Adt and a primitive or pointer type. This can be FFI-safe if non-null
                 // enum layout optimisation is being applied.
                 (Adt(..), _) if is_primitive_or_pointer(b) => {
-                    if let Some(a_inner) = types::repr_nullable_ptr(tcx, param_env, a, ckind) {
+                    if let Some(a_inner) = types::repr_nullable_ptr(tcx, typing_env, a, ckind) {
                         a_inner == b
                     } else {
                         false
                     }
                 }
                 (_, Adt(..)) if is_primitive_or_pointer(a) => {
-                    if let Some(b_inner) = types::repr_nullable_ptr(tcx, param_env, b, ckind) {
+                    if let Some(b_inner) = types::repr_nullable_ptr(tcx, typing_env, b, ckind) {
                         b_inner == a
                     } else {
                         false

compiler/rustc_lint/src/if_let_rescope.rs

@@ -368,7 +368,7 @@ impl<'tcx, 'a> Visitor<'tcx> for FindSignificantDropper<'tcx, 'a> {
             .cx
             .typeck_results()
             .expr_ty(expr)
-            .has_significant_drop(self.cx.tcx, self.cx.param_env)
+            .has_significant_drop(self.cx.tcx, self.cx.typing_env())
         {
             return ControlFlow::Break(expr.span);
         }

compiler/rustc_lint/src/internal.rs

@@ -103,7 +103,8 @@ declare_lint_pass!(QueryStability => [POTENTIAL_QUERY_INSTABILITY, UNTRACKED_QUE
 impl LateLintPass<'_> for QueryStability {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
         let Some((span, def_id, args)) = typeck_results_of_method_fn(cx, expr) else { return };
-        if let Ok(Some(instance)) = ty::Instance::try_resolve(cx.tcx, cx.param_env, def_id, args) {
+        if let Ok(Some(instance)) = ty::Instance::try_resolve(cx.tcx, cx.typing_env(), def_id, args)
+        {
             let def_id = instance.def_id();
             if cx.tcx.has_attr(def_id, sym::rustc_lint_query_instability) {
                 cx.emit_span_lint(POTENTIAL_QUERY_INSTABILITY, span, QueryInstability {
@@ -544,7 +545,7 @@ impl Diagnostics {
     ) {
         // Is the callee marked with `#[rustc_lint_diagnostics]`?
         let Some(inst) =
-            ty::Instance::try_resolve(cx.tcx, cx.param_env, def_id, fn_gen_args).ok().flatten()
+            ty::Instance::try_resolve(cx.tcx, cx.typing_env(), def_id, fn_gen_args).ok().flatten()
         else {
             return;
         };

compiler/rustc_lint/src/let_underscore.rs

@@ -128,7 +128,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
 
             // If the type has a trivial Drop implementation, then it doesn't
             // matter that we drop the value immediately.
-            if !ty.needs_drop(cx.tcx, cx.param_env) {
+            if !ty.needs_drop(cx.tcx, cx.typing_env()) {
                 return;
             }
             // Lint for patterns like `mutex.lock()`, which returns `Result<MutexGuard, _>` as well.

compiler/rustc_lint/src/non_fmt_panic.rs

@@ -157,15 +157,17 @@ fn check_panic<'tcx>(cx: &LateContext<'tcx>, f: &'tcx hir::Expr<'tcx>, arg: &'tc
                 Some(ty_def) if cx.tcx.is_lang_item(ty_def.did(), LangItem::String),
             );
 
-            let infcx = cx.tcx.infer_ctxt().build(cx.typing_mode());
+            let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(cx.typing_env());
             let suggest_display = is_str
-                || cx.tcx.get_diagnostic_item(sym::Display).is_some_and(|t| {
-                    infcx.type_implements_trait(t, [ty], cx.param_env).may_apply()
-                });
+                || cx
+                    .tcx
+                    .get_diagnostic_item(sym::Display)
+                    .is_some_and(|t| infcx.type_implements_trait(t, [ty], param_env).may_apply());
             let suggest_debug = !suggest_display
-                && cx.tcx.get_diagnostic_item(sym::Debug).is_some_and(|t| {
-                    infcx.type_implements_trait(t, [ty], cx.param_env).may_apply()
-                });
+                && cx
+                    .tcx
+                    .get_diagnostic_item(sym::Debug)
+                    .is_some_and(|t| infcx.type_implements_trait(t, [ty], param_env).may_apply());
 
             let suggest_panic_any = !is_str && panic == sym::std_panic_macro;
 

compiler/rustc_lint/src/noop_method_call.rs

@@ -94,9 +94,9 @@ impl<'tcx> LateLintPass<'tcx> for NoopMethodCall {
 
         let args = cx
             .tcx
-            .normalize_erasing_regions(cx.param_env, cx.typeck_results().node_args(expr.hir_id));
+            .normalize_erasing_regions(cx.typing_env(), cx.typeck_results().node_args(expr.hir_id));
         // Resolve the trait method instance.
-        let Ok(Some(i)) = ty::Instance::try_resolve(cx.tcx, cx.param_env, did, args) else {
+        let Ok(Some(i)) = ty::Instance::try_resolve(cx.tcx, cx.typing_env(), did, args) else {
             return;
         };
         // (Re)check that it implements the noop diagnostic.

compiler/rustc_lint/src/tail_expr_drop_order.rs

@@ -103,7 +103,7 @@ impl TailExprDropOrder {
         if matches!(fn_kind, hir::intravisit::FnKind::Closure) {
             for &capture in cx.tcx.closure_captures(def_id) {
                 if matches!(capture.info.capture_kind, ty::UpvarCapture::ByValue)
-                    && capture.place.ty().has_significant_drop(cx.tcx, cx.param_env)
+                    && capture.place.ty().has_significant_drop(cx.tcx, cx.typing_env())
                 {
                     locals.push(capture.var_ident.span);
                 }
@@ -113,7 +113,7 @@ impl TailExprDropOrder {
             if cx
                 .typeck_results()
                 .node_type(param.hir_id)
-                .has_significant_drop(cx.tcx, cx.param_env)
+                .has_significant_drop(cx.tcx, cx.typing_env())
             {
                 locals.push(param.span);
             }
@@ -158,7 +158,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LocalCollector<'a, 'tcx> {
     fn visit_pat(&mut self, pat: &'tcx Pat<'tcx>) {
         if let PatKind::Binding(_binding_mode, id, ident, pat) = pat.kind {
             let ty = self.cx.typeck_results().node_type(id);
-            if ty.has_significant_drop(self.cx.tcx, self.cx.param_env) {
+            if ty.has_significant_drop(self.cx.tcx, self.cx.typing_env()) {
                 self.locals.push(ident.span);
             }
             if let Some(pat) = pat {
@@ -234,7 +234,10 @@ impl<'a, 'tcx> LintTailExpr<'a, 'tcx> {
         if Self::expr_eventually_point_into_local(expr) {
             return false;
         }
-        self.cx.typeck_results().expr_ty(expr).has_significant_drop(self.cx.tcx, self.cx.param_env)
+        self.cx
+            .typeck_results()
+            .expr_ty(expr)
+            .has_significant_drop(self.cx.tcx, self.cx.typing_env())
     }
 }
 

compiler/rustc_lint/src/types.rs

@@ -613,10 +613,11 @@ pub(crate) fn transparent_newtype_field<'a, 'tcx>(
     tcx: TyCtxt<'tcx>,
     variant: &'a ty::VariantDef,
 ) -> Option<&'a ty::FieldDef> {
-    let param_env = tcx.param_env(variant.def_id);
+    let typing_env = ty::TypingEnv::non_body_analysis(tcx, variant.def_id);
     variant.fields.iter().find(|field| {
         let field_ty = tcx.type_of(field.did).instantiate_identity();
-        let is_1zst = tcx.layout_of(param_env.and(field_ty)).is_ok_and(|layout| layout.is_1zst());
+        let is_1zst =
+            tcx.layout_of(typing_env.as_query_input(field_ty)).is_ok_and(|layout| layout.is_1zst());
         !is_1zst
     })
 }
@@ -624,11 +625,11 @@ pub(crate) fn transparent_newtype_field<'a, 'tcx>(
 /// Is type known to be non-null?
 fn ty_is_known_nonnull<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     ty: Ty<'tcx>,
     mode: CItemKind,
 ) -> bool {
-    let ty = tcx.try_normalize_erasing_regions(param_env, ty).unwrap_or(ty);
+    let ty = tcx.try_normalize_erasing_regions(typing_env, ty).unwrap_or(ty);
 
     match ty.kind() {
         ty::FnPtr(..) => true,
@@ -649,7 +650,7 @@ fn ty_is_known_nonnull<'tcx>(
             def.variants()
                 .iter()
                 .filter_map(|variant| transparent_newtype_field(tcx, variant))
-                .any(|field| ty_is_known_nonnull(tcx, param_env, field.ty(tcx, args), mode))
+                .any(|field| ty_is_known_nonnull(tcx, typing_env, field.ty(tcx, args), mode))
         }
         _ => false,
     }
@@ -659,10 +660,10 @@ fn ty_is_known_nonnull<'tcx>(
 /// If the type passed in was not scalar, returns None.
 fn get_nullable_type<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     ty: Ty<'tcx>,
 ) -> Option<Ty<'tcx>> {
-    let ty = tcx.try_normalize_erasing_regions(param_env, ty).unwrap_or(ty);
+    let ty = tcx.try_normalize_erasing_regions(typing_env, ty).unwrap_or(ty);
 
     Some(match *ty.kind() {
         ty::Adt(field_def, field_args) => {
@@ -679,7 +680,7 @@ fn get_nullable_type<'tcx>(
                     .expect("No non-zst fields in transparent type.")
                     .ty(tcx, field_args)
             };
-            return get_nullable_type(tcx, param_env, inner_field_ty);
+            return get_nullable_type(tcx, typing_env, inner_field_ty);
         }
         ty::Int(ty) => Ty::new_int(tcx, ty),
         ty::Uint(ty) => Ty::new_uint(tcx, ty),
@@ -708,10 +709,10 @@ fn get_nullable_type<'tcx>(
 /// - Does not have the `#[non_exhaustive]` attribute.
 fn is_niche_optimization_candidate<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     ty: Ty<'tcx>,
 ) -> bool {
-    if tcx.layout_of(param_env.and(ty)).is_ok_and(|layout| !layout.is_1zst()) {
+    if tcx.layout_of(typing_env.as_query_input(ty)).is_ok_and(|layout| !layout.is_1zst()) {
         return false;
     }
 
@@ -734,7 +735,7 @@ fn is_niche_optimization_candidate<'tcx>(
 /// `core::ptr::NonNull`, and `#[repr(transparent)]` newtypes.
 pub(crate) fn repr_nullable_ptr<'tcx>(
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     ty: Ty<'tcx>,
     ckind: CItemKind,
 ) -> Option<Ty<'tcx>> {
@@ -747,9 +748,9 @@ pub(crate) fn repr_nullable_ptr<'tcx>(
                     let ty1 = field1.ty(tcx, args);
                     let ty2 = field2.ty(tcx, args);
 
-                    if is_niche_optimization_candidate(tcx, param_env, ty1) {
+                    if is_niche_optimization_candidate(tcx, typing_env, ty1) {
                         ty2
-                    } else if is_niche_optimization_candidate(tcx, param_env, ty2) {
+                    } else if is_niche_optimization_candidate(tcx, typing_env, ty2) {
                         ty1
                     } else {
                         return None;
@@ -760,20 +761,20 @@ pub(crate) fn repr_nullable_ptr<'tcx>(
             _ => return None,
         };
 
-        if !ty_is_known_nonnull(tcx, param_env, field_ty, ckind) {
+        if !ty_is_known_nonnull(tcx, typing_env, field_ty, ckind) {
             return None;
         }
 
         // At this point, the field's type is known to be nonnull and the parent enum is Option-like.
         // If the computed size for the field and the enum are different, the nonnull optimization isn't
         // being applied (and we've got a problem somewhere).
-        let compute_size_skeleton = |t| SizeSkeleton::compute(t, tcx, param_env).ok();
+        let compute_size_skeleton = |t| SizeSkeleton::compute(t, tcx, typing_env).ok();
         if !compute_size_skeleton(ty)?.same_size(compute_size_skeleton(field_ty)?) {
             bug!("improper_ctypes: Option nonnull optimization not applied?");
         }
 
         // Return the nullable type this Option-like enum can be safely represented with.
-        let field_ty_layout = tcx.layout_of(param_env.and(field_ty));
+        let field_ty_layout = tcx.layout_of(typing_env.as_query_input(field_ty));
         if field_ty_layout.is_err() && !field_ty.has_non_region_param() {
             bug!("should be able to compute the layout of non-polymorphic type");
         }
@@ -784,10 +785,10 @@ pub(crate) fn repr_nullable_ptr<'tcx>(
                 WrappingRange { start: 0, end }
                     if end == field_ty_scalar.size(&tcx).unsigned_int_max() - 1 =>
                 {
-                    return Some(get_nullable_type(tcx, param_env, field_ty).unwrap());
+                    return Some(get_nullable_type(tcx, typing_env, field_ty).unwrap());
                 }
                 WrappingRange { start: 1, .. } => {
-                    return Some(get_nullable_type(tcx, param_env, field_ty).unwrap());
+                    return Some(get_nullable_type(tcx, typing_env, field_ty).unwrap());
                 }
                 WrappingRange { start, end } => {
                     unreachable!("Unhandled start and end range: ({}, {})", start, end)
@@ -825,7 +826,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
         let field_ty = self
             .cx
             .tcx
-            .try_normalize_erasing_regions(self.cx.param_env, field_ty)
+            .try_normalize_erasing_regions(self.cx.typing_env(), field_ty)
             .unwrap_or(field_ty);
         self.check_type_for_ffi(acc, field_ty)
     }
@@ -988,7 +989,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
                         {
                             // Special-case types like `Option<extern fn()>` and `Result<extern fn(), ()>`
                             if let Some(ty) =
-                                repr_nullable_ptr(self.cx.tcx, self.cx.param_env, ty, self.mode)
+                                repr_nullable_ptr(self.cx.tcx, self.cx.typing_env(), ty, self.mode)
                             {
                                 return self.check_type_for_ffi(acc, ty);
                             }
@@ -1196,7 +1197,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
         if let Some(ty) = self
             .cx
             .tcx
-            .try_normalize_erasing_regions(self.cx.param_env, ty)
+            .try_normalize_erasing_regions(self.cx.typing_env(), ty)
             .unwrap_or(ty)
             .visit_with(&mut ProhibitOpaqueTypes)
             .break_value()
@@ -1220,7 +1221,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             return;
         }
 
-        let ty = self.cx.tcx.try_normalize_erasing_regions(self.cx.param_env, ty).unwrap_or(ty);
+        let ty = self.cx.tcx.try_normalize_erasing_regions(self.cx.typing_env(), ty).unwrap_or(ty);
 
         // C doesn't really support passing arrays by value - the only way to pass an array by value
         // is through a struct. So, first test that the top level isn't an array, and then

compiler/rustc_lint/src/unused.rs

@@ -272,7 +272,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
                 || !ty.is_inhabited_from(
                     cx.tcx,
                     cx.tcx.parent_module(expr.hir_id).to_def_id(),
-                    cx.param_env,
+                    cx.typing_env(),
                 )
             {
                 return Some(MustUsePath::Suppressed);
@@ -556,7 +556,7 @@ impl<'tcx> LateLintPass<'tcx> for PathStatements {
         if let hir::StmtKind::Semi(expr) = s.kind {
             if let hir::ExprKind::Path(_) = expr.kind {
                 let ty = cx.typeck_results().expr_ty(expr);
-                if ty.needs_drop(cx.tcx, cx.param_env) {
+                if ty.needs_drop(cx.tcx, cx.typing_env()) {
                     let sub = if let Ok(snippet) = cx.sess().source_map().span_to_snippet(expr.span)
                     {
                         PathStatementDropSub::Suggestion { span: s.span, snippet }

compiler/rustc_metadata/src/native_libs.rs

@@ -6,7 +6,7 @@ use rustc_ast::CRATE_NODE_ID;
 use rustc_attr as attr;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::query::LocalCrate;
-use rustc_middle::ty::{List, ParamEnv, ParamEnvAnd, Ty, TyCtxt};
+use rustc_middle::ty::{self, List, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_session::config::CrateType;
 use rustc_session::cstore::{
@@ -613,7 +613,7 @@ impl<'tcx> Collector<'tcx> {
             .map(|ty| {
                 let layout = self
                     .tcx
-                    .layout_of(ParamEnvAnd { param_env: ParamEnv::empty(), value: ty })
+                    .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty))
                     .expect("layout")
                     .layout;
                 // In both stdcall and fastcall, we always round up the argument size to the

compiler/rustc_middle/src/mir/consts.rs

@@ -102,10 +102,11 @@ impl<'tcx> ConstValue<'tcx> {
     pub fn try_to_bits_for_ty(
         &self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
         ty: Ty<'tcx>,
     ) -> Option<u128> {
-        let size = tcx.layout_of(param_env.with_reveal_all_normalized(tcx).and(ty)).ok()?.size;
+        let size =
+            tcx.layout_of(typing_env.with_reveal_all_normalized(tcx).as_query_input(ty)).ok()?.size;
         self.try_to_bits(size)
     }
 
@@ -314,7 +315,7 @@ impl<'tcx> Const<'tcx> {
     pub fn eval(
         self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
         span: Span,
     ) -> Result<ConstValue<'tcx>, ErrorHandled> {
         match self {
@@ -333,7 +334,7 @@ impl<'tcx> Const<'tcx> {
             }
             Const::Unevaluated(uneval, _) => {
                 // FIXME: We might want to have a `try_eval`-like function on `Unevaluated`
-                tcx.const_eval_resolve(param_env, uneval, span)
+                tcx.const_eval_resolve(typing_env, uneval, span)
             }
             Const::Val(val, _) => Ok(val),
         }
@@ -343,7 +344,7 @@ impl<'tcx> Const<'tcx> {
     pub fn try_eval_scalar(
         self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<Scalar> {
         if let Const::Ty(_, c) = self
             && let ty::ConstKind::Value(ty, val) = c.kind()
@@ -354,7 +355,7 @@ impl<'tcx> Const<'tcx> {
             // pointer here, which valtrees don't represent.)
             Some(val.unwrap_leaf().into())
         } else {
-            self.eval(tcx, param_env, DUMMY_SP).ok()?.try_to_scalar()
+            self.eval(tcx, typing_env, DUMMY_SP).ok()?.try_to_scalar()
         }
     }
 
@@ -362,23 +363,29 @@ impl<'tcx> Const<'tcx> {
     pub fn try_eval_scalar_int(
         self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<ScalarInt> {
-        self.try_eval_scalar(tcx, param_env)?.try_to_scalar_int().ok()
+        self.try_eval_scalar(tcx, typing_env)?.try_to_scalar_int().ok()
     }
 
     #[inline]
-    pub fn try_eval_bits(&self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> Option<u128> {
-        let int = self.try_eval_scalar_int(tcx, param_env)?;
-        let size =
-            tcx.layout_of(param_env.with_reveal_all_normalized(tcx).and(self.ty())).ok()?.size;
+    pub fn try_eval_bits(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
+    ) -> Option<u128> {
+        let int = self.try_eval_scalar_int(tcx, typing_env)?;
+        let size = tcx
+            .layout_of(typing_env.with_reveal_all_normalized(tcx).as_query_input(self.ty()))
+            .ok()?
+            .size;
         Some(int.to_bits(size))
     }
 
     /// Panics if the value cannot be evaluated or doesn't contain a valid integer of the given type.
     #[inline]
-    pub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> u128 {
-        self.try_eval_bits(tcx, param_env)
+    pub fn eval_bits(self, tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>) -> u128 {
+        self.try_eval_bits(tcx, typing_env)
             .unwrap_or_else(|| bug!("expected bits of {:#?}, got {:#?}", self.ty(), self))
     }
 
@@ -386,21 +393,21 @@ impl<'tcx> Const<'tcx> {
     pub fn try_eval_target_usize(
         self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<u64> {
-        Some(self.try_eval_scalar_int(tcx, param_env)?.to_target_usize(tcx))
+        Some(self.try_eval_scalar_int(tcx, typing_env)?.to_target_usize(tcx))
     }
 
     #[inline]
     /// Panics if the value cannot be evaluated or doesn't contain a valid `usize`.
-    pub fn eval_target_usize(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> u64 {
-        self.try_eval_target_usize(tcx, param_env)
+    pub fn eval_target_usize(self, tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>) -> u64 {
+        self.try_eval_target_usize(tcx, typing_env)
             .unwrap_or_else(|| bug!("expected usize, got {:#?}", self))
     }
 
     #[inline]
-    pub fn try_eval_bool(self, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> Option<bool> {
-        self.try_eval_scalar_int(tcx, param_env)?.try_into().ok()
+    pub fn try_eval_bool(self, tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>) -> Option<bool> {
+        self.try_eval_scalar_int(tcx, typing_env)?.try_into().ok()
     }
 
     #[inline]
@@ -411,17 +418,16 @@ impl<'tcx> Const<'tcx> {
     pub fn from_bits(
         tcx: TyCtxt<'tcx>,
         bits: u128,
-        param_env_ty: ty::ParamEnvAnd<'tcx, Ty<'tcx>>,
+        typing_env: ty::TypingEnv<'tcx>,
+        ty: Ty<'tcx>,
     ) -> Self {
         let size = tcx
-            .layout_of(param_env_ty)
-            .unwrap_or_else(|e| {
-                bug!("could not compute layout for {:?}: {:?}", param_env_ty.value, e)
-            })
+            .layout_of(typing_env.as_query_input(ty))
+            .unwrap_or_else(|e| bug!("could not compute layout for {ty:?}: {e:?}"))
             .size;
         let cv = ConstValue::Scalar(Scalar::from_uint(bits, size));
 
-        Self::Val(cv, param_env_ty.value)
+        Self::Val(cv, ty)
     }
 
     #[inline]
@@ -438,7 +444,8 @@ impl<'tcx> Const<'tcx> {
 
     pub fn from_usize(tcx: TyCtxt<'tcx>, n: u64) -> Self {
         let ty = tcx.types.usize;
-        Self::from_bits(tcx, n as u128, ty::ParamEnv::empty().and(ty))
+        let typing_env = ty::TypingEnv::fully_monomorphized();
+        Self::from_bits(tcx, n as u128, typing_env, ty)
     }
 
     #[inline]

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -351,7 +351,11 @@ impl<'tcx> GlobalAlloc<'tcx> {
         }
     }
 
-    pub fn size_and_align(&self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> (Size, Align) {
+    pub fn size_and_align(
+        &self,
+        tcx: TyCtxt<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
+    ) -> (Size, Align) {
         match self {
             GlobalAlloc::Static(def_id) => {
                 let DefKind::Static { nested, .. } = tcx.def_kind(def_id) else {
@@ -374,7 +378,7 @@ impl<'tcx> GlobalAlloc<'tcx> {
                         .type_of(def_id)
                         .no_bound_vars()
                         .expect("statics should not have generic parameters");
-                    let layout = tcx.layout_of(param_env.and(ty)).unwrap();
+                    let layout = tcx.layout_of(typing_env.as_query_input(ty)).unwrap();
                     assert!(layout.is_sized());
                     (layout.size, layout.align.abi)
                 }

compiler/rustc_middle/src/mir/interpret/queries.rs

@@ -58,7 +58,7 @@ impl<'tcx> TyCtxt<'tcx> {
     #[instrument(level = "debug", skip(self))]
     pub fn const_eval_resolve(
         self,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
         ct: mir::UnevaluatedConst<'tcx>,
         span: Span,
     ) -> EvalToConstValueResult<'tcx> {
@@ -72,14 +72,11 @@ impl<'tcx> TyCtxt<'tcx> {
             bug!("did not expect inference variables here");
         }
 
-        match ty::Instance::try_resolve(
-            self, param_env,
-            // FIXME: maybe have a separate version for resolving mir::UnevaluatedConst?
-            ct.def, ct.args,
-        ) {
+        // FIXME: maybe have a separate version for resolving mir::UnevaluatedConst?
+        match ty::Instance::try_resolve(self, typing_env, ct.def, ct.args) {
             Ok(Some(instance)) => {
                 let cid = GlobalId { instance, promoted: ct.promoted };
-                self.const_eval_global_id(param_env, cid, span)
+                self.const_eval_global_id(typing_env.param_env, cid, span)
             }
             // For errors during resolution, we deliberately do not point at the usage site of the constant,
             // since for these errors the place the constant is used shouldn't matter.
@@ -91,7 +88,7 @@ impl<'tcx> TyCtxt<'tcx> {
     #[instrument(level = "debug", skip(self))]
     pub fn const_eval_resolve_for_typeck(
         self,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
         ct: ty::UnevaluatedConst<'tcx>,
         span: Span,
     ) -> EvalToValTreeResult<'tcx> {
@@ -105,10 +102,10 @@ impl<'tcx> TyCtxt<'tcx> {
             bug!("did not expect inference variables here");
         }
 
-        match ty::Instance::try_resolve(self, param_env, ct.def, ct.args) {
+        match ty::Instance::try_resolve(self, typing_env, ct.def, ct.args) {
             Ok(Some(instance)) => {
                 let cid = GlobalId { instance, promoted: None };
-                self.const_eval_global_id_for_typeck(param_env, cid, span).inspect(|_| {
+                self.const_eval_global_id_for_typeck(typing_env.param_env, cid, span).inspect(|_| {
                     // We are emitting the lint here instead of in `is_const_evaluatable`
                     // as we normalize obligations before checking them, and normalization
                     // uses this function to evaluate this constant.

compiler/rustc_middle/src/mir/mod.rs

@@ -39,7 +39,7 @@ use crate::ty::fold::{FallibleTypeFolder, TypeFoldable};
 use crate::ty::print::{FmtPrinter, Printer, pretty_print_const, with_no_trimmed_paths};
 use crate::ty::visit::TypeVisitableExt;
 use crate::ty::{
-    self, AdtDef, GenericArg, GenericArgsRef, Instance, InstanceKind, List, Ty, TyCtxt, TypingMode,
+    self, AdtDef, GenericArg, GenericArgsRef, Instance, InstanceKind, List, Ty, TyCtxt, TypingEnv,
     UserTypeAnnotationIndex,
 };
 
@@ -452,12 +452,17 @@ impl<'tcx> Body<'tcx> {
         self.basic_blocks.as_mut()
     }
 
-    pub fn typing_mode(&self, _tcx: TyCtxt<'tcx>) -> TypingMode<'tcx> {
+    pub fn typing_env(&self, tcx: TyCtxt<'tcx>) -> TypingEnv<'tcx> {
         match self.phase {
-            // FIXME(#132279): the MIR is quite clearly inside of a body, so we
-            // should instead reveal opaques defined by that body here.
-            MirPhase::Built | MirPhase::Analysis(_) => TypingMode::non_body_analysis(),
-            MirPhase::Runtime(_) => TypingMode::PostAnalysis,
+            // FIXME(#132279): we should reveal the opaques defined in the body during analysis.
+            MirPhase::Built | MirPhase::Analysis(_) => TypingEnv {
+                typing_mode: ty::TypingMode::non_body_analysis(),
+                param_env: tcx.param_env(self.source.def_id()),
+            },
+            MirPhase::Runtime(_) => TypingEnv {
+                typing_mode: ty::TypingMode::PostAnalysis,
+                param_env: tcx.param_env_reveal_all_normalized(self.source.def_id()),
+            },
         }
     }
 
@@ -618,7 +623,7 @@ impl<'tcx> Body<'tcx> {
     }
 
     /// If this basic block ends with a [`TerminatorKind::SwitchInt`] for which we can evaluate the
-    /// dimscriminant in monomorphization, we return the discriminant bits and the
+    /// discriminant in monomorphization, we return the discriminant bits and the
     /// [`SwitchTargets`], just so the caller doesn't also have to match on the terminator.
     fn try_const_mono_switchint<'a>(
         tcx: TyCtxt<'tcx>,
@@ -627,13 +632,15 @@ impl<'tcx> Body<'tcx> {
     ) -> Option<(u128, &'a SwitchTargets)> {
         // There are two places here we need to evaluate a constant.
         let eval_mono_const = |constant: &ConstOperand<'tcx>| {
-            let env = ty::ParamEnv::reveal_all();
+            // FIXME(#132279): what is this, why are we using an empty environment with
+            // `RevealAll` here.
+            let typing_env = ty::TypingEnv::fully_monomorphized();
             let mono_literal = instance.instantiate_mir_and_normalize_erasing_regions(
                 tcx,
-                env,
+                typing_env,
                 crate::ty::EarlyBinder::bind(constant.const_),
             );
-            mono_literal.try_eval_bits(tcx, env)
+            mono_literal.try_eval_bits(tcx, typing_env)
         };
 
         let TerminatorKind::SwitchInt { discr, targets } = &block.terminator().kind else {

compiler/rustc_middle/src/mir/statement.rs

@@ -332,9 +332,9 @@ impl<'tcx> Operand<'tcx> {
         span: Span,
     ) -> Operand<'tcx> {
         debug_assert!({
-            let param_env_and_ty = ty::ParamEnv::empty().and(ty);
+            let typing_env = ty::TypingEnv::fully_monomorphized();
             let type_size = tcx
-                .layout_of(param_env_and_ty)
+                .layout_of(typing_env.as_query_input(ty))
                 .unwrap_or_else(|e| panic!("could not compute layout for {ty:?}: {e:?}"))
                 .size;
             let scalar_size = match val {

compiler/rustc_middle/src/mir/syntax.rs

@@ -20,7 +20,7 @@ use smallvec::SmallVec;
 use super::{BasicBlock, Const, Local, UserTypeProjection};
 use crate::mir::coverage::CoverageKind;
 use crate::ty::adjustment::PointerCoercion;
-use crate::ty::{self, GenericArgsRef, List, Region, Ty, TyCtxt, UserTypeAnnotationIndex};
+use crate::ty::{self, GenericArgsRef, List, Region, Ty, UserTypeAnnotationIndex};
 
 /// Represents the "flavors" of MIR.
 ///
@@ -100,13 +100,6 @@ impl MirPhase {
             MirPhase::Runtime(RuntimePhase::Optimized) => "runtime-optimized",
         }
     }
-
-    pub fn param_env<'tcx>(&self, tcx: TyCtxt<'tcx>, body_def_id: DefId) -> ty::ParamEnv<'tcx> {
-        match self {
-            MirPhase::Built | MirPhase::Analysis(_) => tcx.param_env(body_def_id),
-            MirPhase::Runtime(_) => tcx.param_env_reveal_all_normalized(body_def_id),
-        }
-    }
 }
 
 /// See [`MirPhase::Analysis`].

compiler/rustc_middle/src/query/keys.rs

@@ -467,6 +467,18 @@ impl<'tcx, T: Key> Key for ty::ParamEnvAnd<'tcx, T> {
     }
 }
 
+impl<'tcx, T: Key> Key for ty::PseudoCanonicalInput<'tcx, T> {
+    type Cache<V> = DefaultCache<Self, V>;
+
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.value.default_span(tcx)
+    }
+
+    fn ty_def_id(&self) -> Option<DefId> {
+        self.value.ty_def_id()
+    }
+}
+
 impl Key for Symbol {
     type Cache<V> = DefaultCache<Self, V>;
 
@@ -575,7 +587,7 @@ impl Key for (LocalDefId, HirId) {
     }
 }
 
-impl<'tcx> Key for (ValidityRequirement, ty::ParamEnvAnd<'tcx, Ty<'tcx>>) {
+impl<'tcx> Key for (ValidityRequirement, ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) {
     type Cache<V> = DefaultCache<Self, V>;
 
     // Just forward to `Ty<'tcx>`

compiler/rustc_middle/src/query/mod.rs

@@ -81,8 +81,8 @@ use crate::ty::layout::ValidityRequirement;
 use crate::ty::print::{PrintTraitRefExt, describe_as_module};
 use crate::ty::util::AlwaysRequiresDrop;
 use crate::ty::{
-    self, CrateInherentImpls, GenericArg, GenericArgsRef, ParamEnvAnd, Ty, TyCtxt, TyCtxtFeed,
-    UnusedGenericParams,
+    self, CrateInherentImpls, GenericArg, GenericArgsRef, PseudoCanonicalInput, Ty, TyCtxt,
+    TyCtxtFeed, UnusedGenericParams,
 };
 use crate::{dep_graph, mir, thir};
 
@@ -1341,10 +1341,10 @@ rustc_queries! {
     }
 
     query codegen_select_candidate(
-        key: (ty::ParamEnv<'tcx>, ty::TraitRef<'tcx>)
+        key: PseudoCanonicalInput<'tcx, ty::TraitRef<'tcx>>
     ) -> Result<&'tcx ImplSource<'tcx, ()>, CodegenObligationError> {
         cache_on_disk_if { true }
-        desc { |tcx| "computing candidate for `{}`", key.1 }
+        desc { |tcx| "computing candidate for `{}`", key.value }
     }
 
     /// Return all `impl` blocks in the current crate.
@@ -1406,15 +1406,15 @@ rustc_queries! {
         desc { "computing whether `{}` is `Unpin`", env.value }
     }
     /// Query backing `Ty::needs_drop`.
-    query needs_drop_raw(env: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
+    query needs_drop_raw(env: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
         desc { "computing whether `{}` needs drop", env.value }
     }
     /// Query backing `Ty::needs_async_drop`.
-    query needs_async_drop_raw(env: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
+    query needs_async_drop_raw(env: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
         desc { "computing whether `{}` needs async drop", env.value }
     }
     /// Query backing `Ty::has_significant_drop_raw`.
-    query has_significant_drop_raw(env: ty::ParamEnvAnd<'tcx, Ty<'tcx>>) -> bool {
+    query has_significant_drop_raw(env: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
         desc { "computing whether `{}` has a significant drop", env.value }
     }
 
@@ -1451,7 +1451,7 @@ rustc_queries! {
     /// Computes the layout of a type. Note that this implicitly
     /// executes in "reveal all" mode, and will normalize the input type.
     query layout_of(
-        key: ty::ParamEnvAnd<'tcx, Ty<'tcx>>
+        key: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>
     ) -> Result<ty::layout::TyAndLayout<'tcx>, &'tcx ty::layout::LayoutError<'tcx>> {
         depth_limit
         desc { "computing layout of `{}`", key.value }
@@ -1464,7 +1464,7 @@ rustc_queries! {
     /// NB: this doesn't handle virtual calls - those should use `fn_abi_of_instance`
     /// instead, where the instance is an `InstanceKind::Virtual`.
     query fn_abi_of_fn_ptr(
-        key: ty::ParamEnvAnd<'tcx, (ty::PolyFnSig<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
+        key: ty::PseudoCanonicalInput<'tcx, (ty::PolyFnSig<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
     ) -> Result<&'tcx rustc_target::callconv::FnAbi<'tcx, Ty<'tcx>>, &'tcx ty::layout::FnAbiError<'tcx>> {
         desc { "computing call ABI of `{}` function pointers", key.value.0 }
     }
@@ -1475,7 +1475,7 @@ rustc_queries! {
     /// NB: that includes virtual calls, which are represented by "direct calls"
     /// to an `InstanceKind::Virtual` instance (of `<dyn Trait as Trait>::fn`).
     query fn_abi_of_instance(
-        key: ty::ParamEnvAnd<'tcx, (ty::Instance<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
+        key: ty::PseudoCanonicalInput<'tcx, (ty::Instance<'tcx>, &'tcx ty::List<Ty<'tcx>>)>
     ) -> Result<&'tcx rustc_target::callconv::FnAbi<'tcx, Ty<'tcx>>, &'tcx ty::layout::FnAbiError<'tcx>> {
         desc { "computing call ABI of `{}`", key.value.0 }
     }
@@ -2088,7 +2088,7 @@ rustc_queries! {
 
     /// Do not call this query directly: invoke `try_normalize_erasing_regions` instead.
     query try_normalize_generic_arg_after_erasing_regions(
-        goal: ParamEnvAnd<'tcx, GenericArg<'tcx>>
+        goal: PseudoCanonicalInput<'tcx, GenericArg<'tcx>>
     ) -> Result<GenericArg<'tcx>, NoSolution> {
         desc { "normalizing `{}`", goal.value }
     }
@@ -2245,7 +2245,7 @@ rustc_queries! {
     ///    from `Ok(None)` to avoid misleading diagnostics when an error
     ///    has already been/will be emitted, for the original cause.
     query resolve_instance_raw(
-        key: ty::ParamEnvAnd<'tcx, (DefId, GenericArgsRef<'tcx>)>
+        key: ty::PseudoCanonicalInput<'tcx, (DefId, GenericArgsRef<'tcx>)>
     ) -> Result<Option<ty::Instance<'tcx>>, ErrorGuaranteed> {
         desc { "resolving instance `{}`", ty::Instance::new(key.value.0, key.value.1) }
     }
@@ -2283,7 +2283,7 @@ rustc_queries! {
         desc { "computing the backend features for CLI flags" }
     }
 
-    query check_validity_requirement(key: (ValidityRequirement, ty::ParamEnvAnd<'tcx, Ty<'tcx>>)) -> Result<bool, &'tcx ty::layout::LayoutError<'tcx>> {
+    query check_validity_requirement(key: (ValidityRequirement, ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>)) -> Result<bool, &'tcx ty::layout::LayoutError<'tcx>> {
         desc { "checking validity requirement for `{}`: {}", key.1.value, key.0 }
     }
 

compiler/rustc_middle/src/thir.rs

@@ -905,7 +905,7 @@ impl<'tcx> PatRange<'tcx> {
         &self,
         value: mir::Const<'tcx>,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<bool> {
         use Ordering::*;
         debug_assert_eq!(self.ty, value.ty());
@@ -913,10 +913,10 @@ impl<'tcx> PatRange<'tcx> {
         let value = PatRangeBoundary::Finite(value);
         // For performance, it's important to only do the second comparison if necessary.
         Some(
-            match self.lo.compare_with(value, ty, tcx, param_env)? {
+            match self.lo.compare_with(value, ty, tcx, typing_env)? {
                 Less | Equal => true,
                 Greater => false,
-            } && match value.compare_with(self.hi, ty, tcx, param_env)? {
+            } && match value.compare_with(self.hi, ty, tcx, typing_env)? {
                 Less => true,
                 Equal => self.end == RangeEnd::Included,
                 Greater => false,
@@ -929,17 +929,17 @@ impl<'tcx> PatRange<'tcx> {
         &self,
         other: &Self,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<bool> {
         use Ordering::*;
         debug_assert_eq!(self.ty, other.ty);
         // For performance, it's important to only do the second comparison if necessary.
         Some(
-            match other.lo.compare_with(self.hi, self.ty, tcx, param_env)? {
+            match other.lo.compare_with(self.hi, self.ty, tcx, typing_env)? {
                 Less => true,
                 Equal => self.end == RangeEnd::Included,
                 Greater => false,
-            } && match self.lo.compare_with(other.hi, self.ty, tcx, param_env)? {
+            } && match self.lo.compare_with(other.hi, self.ty, tcx, typing_env)? {
                 Less => true,
                 Equal => other.end == RangeEnd::Included,
                 Greater => false,
@@ -985,9 +985,14 @@ impl<'tcx> PatRangeBoundary<'tcx> {
             Self::NegInfinity | Self::PosInfinity => None,
         }
     }
-    pub fn eval_bits(self, ty: Ty<'tcx>, tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>) -> u128 {
+    pub fn eval_bits(
+        self,
+        ty: Ty<'tcx>,
+        tcx: TyCtxt<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
+    ) -> u128 {
         match self {
-            Self::Finite(value) => value.eval_bits(tcx, param_env),
+            Self::Finite(value) => value.eval_bits(tcx, typing_env),
             Self::NegInfinity => {
                 // Unwrap is ok because the type is known to be numeric.
                 ty.numeric_min_and_max_as_bits(tcx).unwrap().0
@@ -999,13 +1004,13 @@ impl<'tcx> PatRangeBoundary<'tcx> {
         }
     }
 
-    #[instrument(skip(tcx, param_env), level = "debug", ret)]
+    #[instrument(skip(tcx, typing_env), level = "debug", ret)]
     pub fn compare_with(
         self,
         other: Self,
         ty: Ty<'tcx>,
         tcx: TyCtxt<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
+        typing_env: ty::TypingEnv<'tcx>,
     ) -> Option<Ordering> {
         use PatRangeBoundary::*;
         match (self, other) {
@@ -1034,8 +1039,8 @@ impl<'tcx> PatRangeBoundary<'tcx> {
             _ => {}
         }
 
-        let a = self.eval_bits(ty, tcx, param_env);
-        let b = other.eval_bits(ty, tcx, param_env);
+        let a = self.eval_bits(ty, tcx, typing_env);
+        let b = other.eval_bits(ty, tcx, typing_env);
 
         match ty.kind() {
             ty::Float(ty::FloatTy::F16) => {

compiler/rustc_middle/src/ty/adt.rs

@@ -498,12 +498,13 @@ impl<'tcx> AdtDef<'tcx> {
         expr_did: DefId,
     ) -> Result<Discr<'tcx>, ErrorGuaranteed> {
         assert!(self.is_enum());
-        let param_env = tcx.param_env(expr_did);
+
         let repr_type = self.repr().discr_type();
         match tcx.const_eval_poly(expr_did) {
             Ok(val) => {
+                let typing_env = ty::TypingEnv::post_analysis(tcx, expr_did);
                 let ty = repr_type.to_ty(tcx);
-                if let Some(b) = val.try_to_bits_for_ty(tcx, param_env, ty) {
+                if let Some(b) = val.try_to_bits_for_ty(tcx, typing_env, ty) {
                     trace!("discriminants: {} ({:?})", b, repr_type);
                     Ok(Discr { val: b, ty })
                 } else {

compiler/rustc_middle/src/ty/consts.rs

@@ -9,7 +9,7 @@ use tracing::{debug, instrument};
 
 use crate::middle::resolve_bound_vars as rbv;
 use crate::mir::interpret::{LitToConstInput, Scalar};
-use crate::ty::{self, GenericArgs, ParamEnv, ParamEnvAnd, Ty, TyCtxt, TypeVisitableExt};
+use crate::ty::{self, GenericArgs, Ty, TyCtxt, TypeVisitableExt};
 
 mod int;
 mod kind;
@@ -330,17 +330,22 @@ impl<'tcx> Const<'tcx> {
         None
     }
 
-    #[inline]
     /// Creates a constant with the given integer value and interns it.
-    pub fn from_bits(tcx: TyCtxt<'tcx>, bits: u128, ty: ParamEnvAnd<'tcx, Ty<'tcx>>) -> Self {
+    #[inline]
+    pub fn from_bits(
+        tcx: TyCtxt<'tcx>,
+        bits: u128,
+        typing_env: ty::TypingEnv<'tcx>,
+        ty: Ty<'tcx>,
+    ) -> Self {
         let size = tcx
-            .layout_of(ty)
+            .layout_of(typing_env.as_query_input(ty))
             .unwrap_or_else(|e| panic!("could not compute layout for {ty:?}: {e:?}"))
             .size;
         ty::Const::new_value(
             tcx,
             ty::ValTree::from_scalar_int(ScalarInt::try_from_uint(bits, size).unwrap()),
-            ty.value,
+            ty,
         )
     }
 
@@ -353,13 +358,13 @@ impl<'tcx> Const<'tcx> {
     #[inline]
     /// Creates an interned bool constant.
     pub fn from_bool(tcx: TyCtxt<'tcx>, v: bool) -> Self {
-        Self::from_bits(tcx, v as u128, ParamEnv::empty().and(tcx.types.bool))
+        Self::from_bits(tcx, v as u128, ty::TypingEnv::fully_monomorphized(), tcx.types.bool)
     }
 
     #[inline]
     /// Creates an interned usize constant.
     pub fn from_target_usize(tcx: TyCtxt<'tcx>, n: u64) -> Self {
-        Self::from_bits(tcx, n as u128, ParamEnv::empty().and(tcx.types.usize))
+        Self::from_bits(tcx, n as u128, ty::TypingEnv::fully_monomorphized(), tcx.types.usize)
     }
 
     /// Panics if self.kind != ty::ConstKind::Value
@@ -393,15 +398,15 @@ impl<'tcx> Const<'tcx> {
         self.try_to_valtree()?.0.try_to_target_usize(tcx)
     }
 
-    #[inline]
     /// Attempts to evaluate the given constant to bits. Can fail to evaluate in the presence of
     /// generics (or erroneous code) or if the value can't be represented as bits (e.g. because it
     /// contains const generic parameters or pointers).
-    pub fn try_to_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Option<u128> {
+    #[inline]
+    pub fn try_to_bits(self, tcx: TyCtxt<'tcx>, typing_env: ty::TypingEnv<'tcx>) -> Option<u128> {
         let (scalar, ty) = self.try_to_scalar()?;
         let scalar = scalar.try_to_scalar_int().ok()?;
-        let size = tcx.layout_of(param_env.with_reveal_all_normalized(tcx).and(ty)).ok()?.size;
-        // if `ty` does not depend on generic parameters, use an empty param_env
+        let input = typing_env.with_reveal_all_normalized(tcx).as_query_input(ty);
+        let size = tcx.layout_of(input).ok()?.size;
         Some(scalar.to_bits(size))
     }
 

compiler/rustc_middle/src/ty/context.rs

@@ -596,8 +596,16 @@ impl<'tcx> Interner for TyCtxt<'tcx> {
         self.coroutine_is_async_gen(coroutine_def_id)
     }
 
-    fn layout_is_pointer_like(self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
-        self.layout_of(self.erase_regions(param_env.and(ty)))
+    // We don't use `TypingEnv` here as it's only defined in `rustc_middle` and
+    // `rustc_next_trait_solver` shouldn't have to know about it.
+    fn layout_is_pointer_like(
+        self,
+        typing_mode: ty::TypingMode<'tcx>,
+        param_env: ty::ParamEnv<'tcx>,
+        ty: Ty<'tcx>,
+    ) -> bool {
+        let typing_env = ty::TypingEnv { typing_mode, param_env };
+        self.layout_of(self.erase_regions(typing_env).as_query_input(self.erase_regions(ty)))
             .is_ok_and(|layout| layout.layout.is_pointer_like(&self.data_layout))
     }