internal override ImmutableArray <TypeWithAnnotations> GetConstraintTypes(ConsList <TypeParameterSymbol> inProgress, bool canIgnoreNullableContext)
        {
            var constraintTypes = ArrayBuilder <TypeWithAnnotations> .GetInstance();

            _map.SubstituteConstraintTypesDistinctWithoutModifiers(_underlyingTypeParameter, _underlyingTypeParameter.GetConstraintTypes(inProgress, canIgnoreNullableContext), constraintTypes, null);

            TypeWithAnnotations bestObjectConstraint = default;

            // Strip all Object constraints.
            for (int i = constraintTypes.Count - 1; i >= 0; i--)
            {
                TypeWithAnnotations type = constraintTypes[i];
                if (ConstraintsHelper.IsObjectConstraint(type, ref bestObjectConstraint))
                {
                    constraintTypes.RemoveAt(i);
                }
            }

            if (bestObjectConstraint.HasType)
            {
                // See if we need to put Object! or Object~ back in order to preserve nullability information for the type parameter.
                if (!canIgnoreNullableContext && ConstraintsHelper.IsObjectConstraintSignificant(CalculateIsNotNullableFromNonTypeConstraints(), bestObjectConstraint))
                {
                    Debug.Assert(!HasNotNullConstraint && !HasValueTypeConstraint);
                    if (constraintTypes.Count == 0)
                    {
                        if (bestObjectConstraint.NullableAnnotation.IsOblivious() && !HasReferenceTypeConstraint)
                        {
                            bestObjectConstraint = default;
                        }
                    }
                    else
                    {
                        foreach (TypeWithAnnotations constraintType in constraintTypes)
                        {
                            if (!ConstraintsHelper.IsObjectConstraintSignificant(IsNotNullableFromConstraintType(constraintType, out _), bestObjectConstraint))
                            {
                                bestObjectConstraint = default;
                                break;
                            }
                        }
                    }

                    if (bestObjectConstraint.HasType)
                    {
                        constraintTypes.Insert(0, bestObjectConstraint);
                    }
                }
            }

            return(constraintTypes.ToImmutableAndFree());
        }