Re: [lmi] libstdc++ concept checks vs std::regex

[Greg Chicares]

On 2016-05-17 15:22, Vadim Zeitlin wrote:
> On Tue, 17 May 2016 13:08:05 +0000 Greg Chicares <address@hidden> wrote:
> 
> GC> Apparently we can either abandon libstdc++'s concept checks (which
> GC> do have some value),
> 
>  Sorry, I hadn't even realized that we were using them until today, so I'm
> not really qualified to judge how much value do they have. Out of
> curiosity, have they ever helped you to find any problems so far?

undefined reference to `non-virtual thunk to wxChoice::GetCount() const'
  http://lists.nongnu.org/archive/html/lmi/2007-03/msg00065.html

vector of an incomplete type (looks like the same problem in both messages)
  http://lists.nongnu.org/archive/html/lmi/2009-07/msg00012.html
  http://lists.nongnu.org/archive/html/lmi/2010-12/msg00002.html

I'm not sure which of these three macros
  -D_GLIBCXX_DEBUG -D_GLIBCXX_DEBUG_PEDANTIC -D_GLIBCXX_CONCEPT_CHECKS
found those issues. But I think I'll just remove the last one.

> GC> or not use some set of C++11 features that I
> GC> cannot today enumerate beyond demonstrating that it includes <regex>.

[...snip learned commentary (which I did read with interest, thanks)...]

>  As I wrote in the beginning of this email, it's hard to me to judge the
> cost of abandoning the use of libstdc++ concepts as I've never seen any
> benefit of using them in the first place, but I seriously doubt it's
> anywhere near the cost of not fully using C++11 standard library, so I'd
> just remove _GLIBCXX_CONCEPT_CHECKS from workhorse.make unless there is
> some benefit to keeping it that I'm completely missing.

I rebuilt everything with that macro removed, and everything's fine now.