internal bool Equals(FunctionPointerParameterSymbol other, TypeCompareKind compareKind)
 => other.Ordinal == Ordinal &&
 _containingSymbol.Equals(other._containingSymbol, compareKind);
 internal bool Equals(FunctionPointerParameterSymbol other, TypeCompareKind compareKind, IReadOnlyDictionary <TypeParameterSymbol, bool>?isValueTypeOverride)
 => other.Ordinal == Ordinal &&
 _containingSymbol.Equals(other._containingSymbol, compareKind, isValueTypeOverride);