Re: [Boost-build] Instrument Source Code

From: Vladimir Prus (ghost_at_[hidden])
Date: 2005-11-23 11:13:03

Hi Franz,

> I have some C++ source and header files which i would like to
> 'instrument' before they are compiled. The processing is done by a
> script and the resulting files are put in an other directory:
>
>    sources = [ glob org/*.cpp org/*.hpp ] ;
>
>    addDumpInfo instrumented_sources : $(sources) ;
>
>    exe Appl : instrumented_sources ;

Should be possible. I have a pretty contrived pipeline which compiles C files 
to assembler, then instruments assembler, then done other things.

>
> I couldn't figure out how to do this with BJam V2. Can I somehow write a
> generator where source type and the target type are the same?
>
> I tried to copy and modify the install rule but had the problem, that
> when an original header file was newer than one of the original source
> files with used that header, bjam always 'instrumented' that file.

BTW, in future it's good idea to include a project on which your problem 
reproduces. With this specific problem I've guessed the problem, but it might 
not work the next time.

Here's the problem: in implementation of install rule, file stage.jam, rule 
copy-file has this code:

    new-a = [ new action $(source) : common.copy : $(properties) ] ;    
    local source-root = [ $(properties).get <install-source-root> ] ;

The problem is that 'actualize' method of the 'action' class has default 
behaviour of getting scanner for each source target (depending on type), and 
using that scanner. That's a bug, it was supposed that "install" don't scan 
header dependencies.

The fix and a test are in CVS now. I attach a patch for your reference -- I 
hope you'll be able to adjust your own code to avoid reinstrumentation when 
header changes.

Thanks,
Volodya