DestructuredConst split mir and ty

compiler/rustc_const_eval/src/const_eval/mod.rs

@@ -100,7 +100,7 @@ pub(crate) fn try_destructure_mir_constant<'tcx>(
     tcx: TyCtxt<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     val: mir::ConstantKind<'tcx>,
-) -> InterpResult<'tcx, mir::DestructuredMirConstant<'tcx>> {
+) -> InterpResult<'tcx, mir::DestructuredConstant<'tcx>> {
     trace!("destructure_mir_constant: {:?}", val);
     let ecx = mk_eval_cx(tcx, DUMMY_SP, param_env, false);
     let op = ecx.const_to_op(&val, None)?;
@@ -129,7 +129,7 @@ pub(crate) fn try_destructure_mir_constant<'tcx>(
         .collect::<InterpResult<'tcx, Vec<_>>>()?;
     let fields = tcx.arena.alloc_from_iter(fields_iter);
 
-    Ok(mir::DestructuredMirConstant { variant, fields })
+    Ok(mir::DestructuredConstant { variant, fields })
 }
 
 #[instrument(skip(tcx), level = "debug")]

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

@@ -211,7 +211,7 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         param_env: ty::ParamEnv<'tcx>,
         constant: mir::ConstantKind<'tcx>,
-    ) -> mir::DestructuredMirConstant<'tcx> {
+    ) -> mir::DestructuredConstant<'tcx> {
         self.try_destructure_mir_constant(param_env.and(constant)).unwrap()
     }
 }

compiler/rustc_middle/src/mir/query.rs

@@ -392,16 +392,9 @@ pub enum ClosureOutlivesSubject<'tcx> {
     Region(ty::RegionVid),
 }
 
-/// The constituent parts of a type level constant of kind ADT or array.
-#[derive(Copy, Clone, Debug, HashStable)]
-pub struct DestructuredConst<'tcx> {
-    pub variant: Option<VariantIdx>,
-    pub fields: &'tcx [ty::Const<'tcx>],
-}
-
 /// The constituent parts of a mir constant of kind ADT or array.
 #[derive(Copy, Clone, Debug, HashStable)]
-pub struct DestructuredMirConstant<'tcx> {
+pub struct DestructuredConstant<'tcx> {
     pub variant: Option<VariantIdx>,
     pub fields: &'tcx [ConstantKind<'tcx>],
 }

compiler/rustc_middle/src/query/mod.rs

@@ -1007,7 +1007,9 @@ rustc_queries! {
 
     /// Tries to destructure an `mir::ConstantKind` ADT or array into its variant index
     /// and its field values.
-    query try_destructure_mir_constant(key: ty::ParamEnvAnd<'tcx, mir::ConstantKind<'tcx>>) -> Option<mir::DestructuredMirConstant<'tcx>> {
+    query try_destructure_mir_constant(
+        key: ty::ParamEnvAnd<'tcx, mir::ConstantKind<'tcx>>
+    ) -> Option<mir::DestructuredConstant<'tcx>> {
         desc { "destructuring mir constant"}
         remap_env_constness
     }

compiler/rustc_typeck/src/coherence/orphan.rs

@@ -5,7 +5,6 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::struct_span_err;
 use rustc_errors::{Diagnostic, ErrorGuaranteed};
 use rustc_hir as hir;
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::subst::InternalSubsts;
 use rustc_middle::ty::util::IgnoreRegions;
@@ -229,12 +228,8 @@ fn emit_orphan_check_error<'tcx>(
                 "only traits defined in the current crate {msg}"
             );
             err.span_label(sp, "impl doesn't use only types from inside the current crate");
-            for (ty, is_target_ty) in &tys {
+            for &(mut ty, is_target_ty) in &tys {
-                let mut ty = *ty;
+                ty = tcx.erase_regions(ty);
-                tcx.infer_ctxt().enter(|infcx| {
-                    // Remove the lifetimes unnecessary for this error.
-                    ty = infcx.freshen(ty);
-                });
                 ty = match ty.kind() {
                     // Remove the type arguments from the output, as they are not relevant.
                     // You can think of this as the reverse of `resolve_vars_if_possible`.
@@ -264,7 +259,7 @@ fn emit_orphan_check_error<'tcx>(
                 };
 
                 let msg = format!("{} is not defined in the current crate{}", ty, postfix);
-                if *is_target_ty {
+                if is_target_ty {
                     // Point at `D<A>` in `impl<A, B> for C<B> in D<A>`
                     err.span_label(self_ty_span, &msg);
                 } else {