Re: [boost] Strange libstdc++ versions in travis-ci testers

Subject: Re: [boost] Strange libstdc++ versions in travis-ci testers
From: Andrzej Krzemienski (akrzemi1_at_[hidden])
Date: 2018-06-28 22:10:23

2018-06-28 23:34 GMT+02:00 Peter Dimov via Boost <boost_at_[hidden]>:

> Andrzej Krzemienski wrote:
>
> This is interesting. I am referring to Boost.Opitonal tests on Travis
>> configured here: https://travis-ci.org/boostorg/optional
>> I am a maintainer of Boost.Optional, and I never configured these tests.
>> They were not there a year ago, and at some point I started receiving
>> test results from this site upon every commit.
>>
>
> Yeah, that's my fault.
>
> https://github.com/boostorg/optional/commit/e9f5641be37750a8
> 976546ecfffbcb8ee08f8648
>
> The default libstdc++ on Travis matches the default g++, which is at
> present 4.8, if I'm not mistaken. Each g++ uses its corresponding
> libstdc++, so the default one is used only by Clang; but if a newer one is
> installed, Clang picks that up. So given the .travis.yml file from the
> above commit, clang 3.5, 3.8, 3.9 use libstdc++ 4.9 (because it's being
> installed), the rest use the default one. This is presumably because those
> versions failed with libstdc++ 4.8 at the time I activated Travis.
>

Thanks for the info.

> To detect the actual libstdc++ version, you should use the Boost.Config
> macro, as it's generally more reliable.
>

Do you mean macro BOOST_STDLIB ? In what way is it more reliable? It gives
me a string like "GNU libstdc++ version 20180125" and it would be difficult
to use #ifdef-s on it.

BTW, is there a known way to tell the library series 4.9 from from series
5.0? The date alone does not seem to be good enough.

Regards,
&rzej;