Re: [Boost-cmake] Variant Builds and missing libraries

Subject: Re: [Boost-cmake] Variant Builds and missing libraries
From: Michael Jackson (mike.jackson_at_[hidden])
Date: 2008-11-30 10:38:09

On Nov 29, 2008, at 2:59 AM, Vladimir Prus wrote:

> David Abrahams wrote:
>
>>
>> on Wed Nov 26 2008, Michael Jackson <mike.jackson-AT- 
>> bluequartz.net> wrote:
>>
>>> Taking a deeper look into this issue (by experimenting with bjam)  
>>> this
>>> is what I am seeing (at least on OS X).
>>>
>>> bjam errors on the side of building if I don't quite give it the  
>>> right
>>> information. For instance in the program_options testing I do the
>>> following:
>>>
>>>  bjam cmdline_test_dll toolset=darwin variant=debug link=static
>>>
>>> and I actually get a shared program_options library built, which  
>>> is what the
>>> regression test needs, but I don't actually get a static   
>>> program_options library
>>> built.
>>
>> Because the regression test doesn't need it.  That's not erring on  
>> the
>> side of building; that's erring on the side of doing what's  
>> specified by
>> the Jamfile if it conflicts with the command-line.
>>
>> There's some rationale for that
>> (http://zigzag.cs.msu.su/boost.build/wiki/AlternativeSelection#Example2 
>> )
>> even though Boost.Build doesn't hew to that rationale consistently.
>>
>>> I also noticed that if I start adding multiple configurations (like
>>> single and multi-threading) I will get multiple versions of the
>>> regression test created.
>>
>> I can't see what possible alternative you could have expected.
>>
>>> (Which answered another question that I was going to ask).
>>>
>>> Currently the CMake system will NOT do any of this. If this is the
>>> behavior that is wanted then the logic will need to be added to the
>>> cmake build files.
>>
>> IIUC, CMake doesn't naturally build multiple variants in one build
>> command.  It was my conclusion, along with Doug G., that such
>> multiple-configuration builds should be handled by an external driver
>> script rather than trying to get CMake to do something for which it
>> isn't designed.  I'm not sure how well that fits with Boost's testing
>> regime, though.  When I look at the Jamfile for program_options it  
>> seems
>> to be specifying two specific configurations to test.
>
> Yes, it does. I think that for compiled libraries, it's a good idea to
> have both static and shared linking tested, whereas for header-only
> libraries, the chances that static/shared linking affects anything are
> close to zero. Therefore, test arrangement where header-only libraries
> are tested in one variant, and compiled libraries are tested in
> both static and shared variants appears to be a reasonable compomise
> between testing speed and coverage.
>
> - Volodya

So are you saying you would want to see cmake test all variants in a  
single build directory or have multiple build directories, one for  
each variant?

_________________________________________________________
Mike Jackson                  mike.jackson_at_[hidden]
BlueQuartz Software                    www.bluequartz.net
Principal Software Engineer                  Dayton, Ohio