[CMake] Parallel build & test problem

[Marcel Loose]

On Mon, 2011-05-23 at 07:21 -0400, David Cole wrote:
> On Mon, May 23, 2011 at 4:13 AM, Marcel Loose <loose at astron.nl> wrote:
>         Hi all,
>         
>         A colleague of mine reported a bug in our CMake-base build
>         system when
>         doing a parallel build of multiple targets where one of the
>         targets is
>         'test'.
>         
>         <quote>
>                Running 'make -j16 tMutex test' (or any test other than
>         tMutex)
>                for example will result in building tMutex in parallel
>         to
>                testing it.
>         
>                Expected behaviour is first building tMutex, followed
>         by running
>                the tests.
>         </quote>
>         
>         Is this indeed a bug? Either in our build system or in CMake?
>         AFAIK it is not possible to define dependencies between the
>         'test'
>         target and the target to build the test program. Correct?
>         
>         Best regards,
>         Marcel Loose.
>         
>         
>         --
>         Marcel Loose
>         Senior Software Engineer, Computing Group R&D, Astron, the
>         Netherlands
>         
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> 
> To the best of my knowledge you can only do a parallel make of one
> target at a time.
> 
> 
> The best way to do what you want is to do two parallel make runs in
> sequence, like this:
> 
> 
>   make -j16 tMutex
>   make -j16 test
> 
> 
> The test target is defined by CMake, though, and runs all tests.
> 
> 
> HTH,
> David
> 
> 

Hi David,

I vaguely remembered that limitation of 'make' as well, but I couldn't
find any relevant pointers on this, and colleagues questioned this
alleged limitation. Therefore I thought it might be a limitation of
CMake, or maybe I should say: the combination of CMake and make.

Anyway, my response was also to do two separate 'make' calls, one for
each target.

Regards,
Marcel Loose.