[typetraits.inl] msvc __is_aggregate error about bx HOT 6 CLOSED

Yeah, your fix with !! is fine, no need to change, I just want to understand the issue, and then do fix.
I also noticed __is_aggregate changes behavior depending on C++ standard set. For example I tested between 14 vs 17.

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A little testing reveals a simple fix:

template<typename Ty>
inline constexpr bool isAggregate()
{
	return !!__is_aggregate(Ty);
}

Not sure why, but that seems to fix it. I guess it is bug after all.

A few quick tests confirm that the function can detect aggregate types correctly.
That being said, I am not very well versed with this typetrait stuff..

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I noticed a little compiler issue with msvc and the __is_aggregate function.

You get this compiler error without instantiating template?

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Can you reproduce the issue on compiler explorer?
https://godbolt.org/z/986fraTdj

I just tried it and not getting any issue with different versions of MSVC compiler.

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So i can reproduce it from msvc v19.30 onwards (i am on latest).
Interestingly only with C++20 enabled.
https://godbolt.org/z/KWYh9888W

Perhaps it got deprecated?
It works with

template<typename Ty>
inline constexpr bool isAggregate()
{
    const bool res = __is_aggregate(Ty);
    return res;
}

Also, Instantiation is not necessary just code generation in general.
Apparently the compiler will generate template functions, even if not in use...

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Works like charm now. Thanks :)

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