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Re: [std-proposals] Extend std::type_info with more information

From: Frederick Virchanza Gotham <cauldwell.thomas_at_[hidden]>
Date: Mon, 8 Apr 2024 11:00:50 +0100
On Mon, Apr 8, 2024 at 4:04 AM Thiago Macieira wrote:
> That section starts with "There has been recent discussion about making major
> additions to" but doesn't link to papers or committee minutes where said
> discussion happened. Therefore, I am discounting it as "it never happened".

Arthur brought it up in a post a few weeks ago here. Do I have to
prove Arthur's existence? I have photographs. (Although with the way
the whole 'deep fake' thing is going... in about 10 years' time
photographs will no longer be admissible as evidence). I wonder how
many years it will be before videos aren't admissible as evidence (the
new Lion King movie was amazing realistic).

> > There won't be an extra payload penalty if we first try to make an
> > exhaustive list of what's /already/ available on Itanium ABI and
> > Microsoft ABI.
> This information isn't there. Since it isn't there, the information can't be
> offered for code that is being compiled today.

With the Itanium ABI, there's a bit of information there, such as
IsClass, IsIntrinsic, IsPointer, IsPointerToMember.

When it comes to Microsoft . . . I've had a look through their header
file for 'type_info' but it calls proprietary functions found in
"vcruntime140.dll". There's a guy in Microsoft named Raymond Chen who
writes a blog (OldNewThing) about stuff along these lines, so just now
I sent him an email asking if he'd reveal what Microsoft have inside
the type_info. If he doesn't reply then I'll keep playing around
incrementing and decrementing through a std::type_info, dereferencing
what might look like a memory address, then increment / decrement /
dereference til I find something.

Received on 2024-04-08 10:01:03