Re: [boost] [Release] Boost 1.70.0 Beta 1 Release Candidate 2

Subject: Re: [boost] [Release] Boost 1.70.0 Beta 1 Release Candidate 2
From: Peter Dimov (pdimov_at_[hidden])
Date: 2019-03-10 17:33:48

Steven Watanabe wrote:

> > The purpose of that incrementing library-id, as far as I can infer, is 
> > to enable two libraries to have their own private zlib dependencies.
>
> That's not really correct.  The reason for the library-id is to make sure 
> that target alternative selection only
happens at the top level on the /zlib//zlib target.

So it's intended for cases like

using zlib : 1.2.7 : <source>C:/Devel/src/zlib-1.2.7 : <toolset>msvc ;
using zlib : 1.2.7 : <source>/opt/src/zlib-1.2.7 : <toolset>gcc ;

?

Either way, in general, when I see lib1 having a CMake dependency on foo.1 
and lib2 having a dependency on foo.2, ignoring the suffix doesn't seem 
correct.

I could add a specific check for `zlib.*` and `bzip2.*` but this will only 
work for Iostreams.

What's the intended path forward (in general, not specifically for the CMake 
configurations) when a second Boost library wants to use zlib and bzip2?