[boost] [testing] Add a tester with hidden visibility

Subject: [boost] [testing] Add a tester with hidden visibility
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2015-05-07 09:40:33

Hi,

Is it possible to add a tester that enables hidden visibility (-
fvisibility=hidden -fvisibility-inlines-hidden) when building and testing 
Boost? I believe, a single tester on Linux+GCC would be enough to discover 
most issues related to symbol visibility.

The reason I'm asking is that I believe Boost should support building with 
hidden visibility by default. This mode allows more optimizations and does not 
export unintended symbols from libraries.

I've set hidden visibility for Boost.Log (in develop) and, as I understand, 
Robert is doing a similar change in Boost.Serialization. However, when 
building 1.58 with hidden visibility for my project I found out that not all 
libraries work well with that setting.

What do you think about it?