Debug assertion and constexpr

[Jonathan Wakely]

On 27/07/15 21:16 +0200, François Dumont wrote:
>Hello
>
>    There are at the moment several failures in the libstdc++ testsuite
>when run in debug mode (_GLIBCXX_DEBUG). This is so because debug
>assertions are not const expressions. Several debug assertions have been
>removed because of this issue.
>
>    So is there a way to define a function as to be ignored in the
>context of a const expression ? If not could we add one ?

No, there is no way without making non-standard front end changes.

I think we should wait and see if
http://cplusplus.github.io/LWG/lwg-active.html#2234 get resolved, then
we can use __builtin_assert() in constexpr functions. It won't give
us the full Debug Mode assertion powers, so no pretty messages
containing formatted information, but we could still assert.