[STDCXX-975] [MSVC 8/9] template parsing fails when using less than comparison in metaprogramming conditional

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: External

Environment

MSVC 8.0, 9.0

• Severity: Compiler Error
• Assignee: Unassigned
• Reporter: Travis Vitek
• Created: 26/Jun/08 21:02
• Updated: 26/Jun/08 21:09

Description

The following code fails to compile under both MSVC 8.0 and 9.0.

template <bool Select, class TypeT, class TypeU>
struct conditional
{
    typedef TypeT type;
};

template <class TypeT, class TypeU>
struct conditional<false, TypeT, TypeU>
{
    typedef TypeU type;
};

template <class TypeT>
struct size_of
{
    enum { value = sizeof (TypeT) };
};

template <class Type1, class Type2, class Type3, class Type4>
struct largest
{
    typedef typename
    conditional<(size_of<Type1>::value < size_of<Type2>::value),
                     Type2, Type1>::type Type12;

    typedef typename
    conditional<(size_of<Type3>::value < size_of<Type4>::value),
                     Type3, Type4>::type Type34;
};

An issue has been filed with the vendor here.