Structurallyresolve adts and tuples expectations too

Author: compiler-errors

compiler/rustc_hir_typeck/src/expr.rs

@@ -1783,7 +1783,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 expr:&'tcx hir::Expr<'tcx>,
 ) -> Ty<'tcx>{
 let flds = expected.only_has_type(self).and_then(|ty| {
-let ty = self.resolve_vars_with_obligations(ty);
+let ty = self.try_structurally_resolve_type(expr.span,ty);
 match ty.kind(){
  ty::Tuple(flds) => Some(&flds[..]),
  _ => None,
@@ -1861,7 +1861,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 ){
 let tcx = self.tcx;
 
-let adt_ty = self.resolve_vars_with_obligations(adt_ty);
+let adt_ty = self.try_structurally_resolve_type(span,adt_ty);
 let adt_ty_hint = expected.only_has_type(self).and_then(|expected| {
 self.fudge_inference_if_ok(|| {
 let ocx = ObligationCtxt::new(self);

tests/ui/traits/next-solver/typeck/guide-ctors.rs

@@ -0,0 +1,32 @@
+//@ compile-flags: -Znext-solver
+//@ check-pass
+
+// Makes sure we structurally normalize before trying to use expectation to guide
+// coercion in adt and tuples.
+
+use std::any::Any;
+
+traitCoerce{
+typeAssoc;
+}
+
+structTupleGuidance;
+implCoerceforTupleGuidance{
+typeAssoc = (&'staticdynAny,);
+}
+
+structAdtGuidance;
+implCoerceforAdtGuidance{
+typeAssoc = Adt<&'staticdynAny>;
+}
+
+structAdt<T>{
+f:T,
+}
+
+fnfoo<'a,T:Coerce>(_:T::Assoc){}
+
+fnmain(){
+foo::<TupleGuidance>((&0u32,));
+foo::<AdtGuidance>(Adt{f:&0u32});
+}