Re: [Boost-build] BJam "Duplicate name of actual target" problem

Subject: Re: [Boost-build] BJam "Duplicate name of actual target" problem
From: Gevorg Voskanyan (v_gevorg_at_[hidden])
Date: 2011-07-15 11:24:10

Hite, Christopher wrote:

> I want to compile two variants of the same program with  overlapping
> subsets of cpps.  I've split up my code so that I don't need  any
> annoying ifdefs.  So my Jamfile looks something like  this:
> 
> alias shared :  [ glob *.cpp ] ;
> 
> alias  x : [ glob  x/*.cpp ]  ../libs/xlib//xlib ;
> alias  y : [ glob y/*.cpp ]   ../libs/ylib//ylib ; 
> 
> exe prog_x  : shared x : <include>.  ;
> exe prog_y  : shared y : <include>. ;
> 
> 1) "Duplicate name  of actual target" - The reason why is that xlib/ylib
> infect the compilation  of files in shared.  All the cpps for an exe are
> compiled with the same  include path.
> 
> Yes I've read the  faq:
> http://www.boost.org/boost-build2/doc/html/bbv2/faq/s02.html
> 
> 2) I  tried was defining shared as a lib.  The problem with this is  that
> shared and x(or y) are circularly dependent.
> ??? Can I get bjam to  pass --start-group --end-group through g++ to ld?
> 
> 3) A solution would be  to define an shared as an obj.  The problem here
> is if shared has 50 cpp  files, each one needs a separate obj in the
> Jamfile.
> !!! Feature request -  and objgroup which would work like lib, so cpp
> files in shared wouldn't get  settings from x or y.

# WARNING: untested

rule objgroup ( sources + )
{
   local g = ;
   for s in $(sources) {
      local name = $(s:B) ;
      obj $(name) : $(s) ;
      g += $(name) ;
   }
   return $(g) ;
}

alias shared : [ objgroup [ glob *.cpp ] ] ;

> 4) I could try things like feature.feature or  variant, but they would
> envolve compiling shared  twice.
> 
> Chris

HTH,
Gevorg