Structurally normalize again for byte string lit pat checking

Author: compiler-errors

compiler/rustc_hir_typeck/src/pat.rs

@@ -394,8 +394,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let mut pat_ty = ty;
         if let hir::ExprKind::Lit(Spanned { node: ast::LitKind::ByteStr(..), .. }) = lt.kind {
             let expected = self.structurally_resolve_type(span, expected);
-            if let ty::Ref(_, inner_ty, _) = expected.kind()
-                && matches!(inner_ty.kind(), ty::Slice(_))
+            if let ty::Ref(_, inner_ty, _) = *expected.kind()
+                && self.try_structurally_resolve_type(span, inner_ty).is_slice()
             {
                 let tcx = self.tcx;
                 trace!(?lt.hir_id.local_id, "polymorphic byte string lit");

tests/ui/traits/new-solver/slice-match-byte-lit.rs

@@ -1,5 +1,5 @@
 // compile-flags: -Ztrait-solver=next
-// known-bug: rust-lang/trait-system-refactor-initiative#38
+// check-pass
 
 fn test(s: &[u8]) {
     match &s[0..3] {