Re: [jamboost] <file> specifier in library causes Duplicate name for actual target

From: Michael Stevens (Michael.Stevens_at_[hidden])
Date: 2004-02-10 13:26:14

Hi Volodya,

> The <file> feature is going to be deprecated in M10 and removed some time 
> after that. You can use
>  
>    alias lapack : : lapack.a ;

Thanks for the reply. Certainly seems logical that the <file> should be 
deprecated in favour of the alias system. I assume your example should read.
   alias lapack : lapack.a ;
 
Looking into my own problem the the matter seems rather more complicated :-(
The problem revolves around the different way library sources are interpreted. 

Previously I was using the follow complex definition:
# System libraries - specify local link requirements for lapack
lib g2c : : <name>g2c ;
lib lapack : : <name>lapack ;
lib lapack : : <toolset>gcc <name>lapack : : <library>g2c ;
lib lapack : : <toolset>intellinux <name>lapack : : <library>g2c ;
lib lapack : : <toolset>msvc <file>"../../CLAPACK3/clapack7.a" ;
# The executable for testing
exe rtheta : rtheta.cpp lapack ;

This works fine (ignoring the <file> Duplicate name issue).

In theory I would like to move the usage-requirement for g2c into the sources 
thus:
lib g2c : : <name>g2c ;
lib lapack : g2c : <toolset>gcc <name>lapack ;

However this seems non functional when static linking. The library g2c is 
never propagated to an exe as a dependency. Similar the simpler
lib lapack : g2c : <name>lapack ;
does not propgate the g2c library dependency.

I am not sure if this a bug or I am missing something seriously important 
about how dependant libraries specified in sources list work when combined 
with a <named> library.

On to the real problem. With regard to using alias definitions in this complex 
case. I can define my alias thus.
alias clapack3_msvc : "../../CLAPACK3/clapack7.a" ;

If I use this directly in the list of exe sources (instead of lapack) things 
are still good. However implementing the toolset dependant linking is not 
possible.
lib lapack : clapack3_msvc : <toolset>msvc <link>static;
fails in horribly with "clapack7.STATIC_LIB " as an unused source. This also 
happens if we place the named library directly into the list of sources thus:
lib lapack : "../../CLAPACK3/clapack7.a" : <toolset>msvc <link>static;

It seems that the logic for lib is going to be somewhat compilcated to 
implment all this correctly!

Hope this all makes sense.

Michael
-- 
___________________________________
Michael Stevens Systems Engineering
Navigation Systems, Estimation and
Bayesian Filtering
http://www.sf.net/Bayes++
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