[PATCH] 1/2 Make _GLIBCXX_DEBUG checks constexpr compatible

[Jonathan Wakely]

On 08/11/20 15:06 +0100, François Dumont via Libstdc++ wrote:
>Now that __glibcxx_assert is constexpr compatible we can do the same 
>for the _GLIBCXX_DEBUG equivalent.
>
>I had also try to do the same on my own so this patch contains the 
>string_view tests I had written when doing so.
>
>I plan to activate some _GLIBCXX_DEBUG checks when _GLIBCXX_ASSERTIONS 
>is defined but only the contant time checks. Is it ok to run checks 
>like __check_partitioned_lower in constexpr ?

Hmm, I don't *think* it's possible to detect the additional calls to
the comparison function during constant evaluation. So I think the
only concern is the extra work the compiler has to do, i.e. the extra
time it takes to compile.

The constant-time checks should be OK though.


>Â Â Â  libstdc++: Make _GLIBCXX_DEBUG checks constexpr compatible
[snip]
>Ok to commit ?

Yes, thanks.