Subject: Re: [boost] [testing] Add a tester with hidden visibility
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2015-05-07 12:02:40
On Thursday 07 May 2015 07:54:14 Robert Ramey wrote:
> I've recently had experience with just this question while maintaining the
> serialization library.
>
> The serialization library can be built as a DLL. The windows version builds
> with MSVC only exporting those symbols which are required from outside.
> That is, it builds with the MSVC of visibility=hidden.
>
> I set visibility=hidden in the jam file and built with gcc. The library
> then failed to link with most of the tests. So I had to update the source
> code to support the attributes for symbol export on those functions which
> need to be exported. It sounds simple, but getting this right in a way that
> supports both gcc and MSVC is tricky and hard to get correct. I got the
> gcc to build and pass all test, but now the MSVC is broken. Unfortunately,
> our testing system truncates the error message so I can't see why the
> current branch in develop fails to build. I'm still waiting from a
> response from the boost build team.
>
> In the course of addressing this, I figured - how hard can this be and
> decided to see how other libraries do it. Checking the jam files of other
> libraries - there are only a few which actually build as DLLS, I found that
> no one actually builds with visibility=hidden. I would be very surprised if
> any of them actually build correctly with this switch set. To do this, it
> has to be done for each individual library. You can't just add the switch
> and re-build.
I'm not sure I understand your point. Unless we don't plan to ever support
hidden visibility, we at least need to start testing this configuration.