Re: [Boost-build] Multi-directory project options

From: Phillip Seaver (phil_at_[hidden])
Date: 2007-03-28 08:23:35

Benn Bollay wrote:
>
> Hi all –
>
>  
>
> I have a single project that spans multiple directories.  I’d like either:
>
>             a) all the source files in all the specified directories
> are compiled into a single executable OR
>

For this case, you can do:

exe single : [ glob dir1/*.c* ] [ glob dir2/*.c* ] [ glob dir3/*.c* ] ;

>             b) as each lib is created for each directory, it uses
> compilation options specified at a single location.
>
For this, you can put a "use-project /name : path/to/lib/dir ;" in your
Jamroot where "/name" is the unique name you want to refer to the
library using and "path/to/lib/dir" is the path (relative to Jamroot's
directory) to the directory containing the Jamfile.v2 for compiling that
library.  You can then use "/name" in your exe and lib sources to get
the usage requirements and cause it to be linked in.

Jamroot (in /project/src, e.g.):

    use-project /a : libs/a ;
    use-project /b : libs/b ;

Jamfile.v2 in /project/src/libs/a:

    lib a : [ glob *.c* ] # sources
        : <define>A_DEFINE_INT # build requirements (always used)
        : # default build settings (used if not overridden by some other
    build requirement)
        : <include>. <define>A_DEFINE_EXT # usage requirements
    ;

Jamfile.v2 in /project/src/libs/b:

    lib b : [ glob *.c* ] /a
        :
        :
        : <include>.
    ;

Jamfile.v2 in /project/src/progs/foo:

    exe foo : [ glob *.c* ] /b ;

So, in the above example, A_DEFINE_INT will be defined while compiling
"a" ("-DA_DEFINE_INT" would be passed to the compiler, e.g.).  The
"<include>. <define>A_DEFINE_EXT" will be used in the build for anything
that refers to "a" in its sources as in "b".

When the <include> feature is converted to the command-line parameters
for "b", it figures out the relative path and passes "-I../a" to the
compiler for "b".  It will also pass "-DA_DEFINE_EXT" for compiling "b".

The "foo" exe will get something like "-DA_DEFINE_EXT -I../../lib/a
-I../../lib/b" on its command-line as well as link against the compiled
"a" and "b" libs.

As for the compilation options, I'd need more information to answer that
question, but you can do something like this in your Jamroot:

    project proj
        : requirements <define>SOMETHING # this will get added to all builds
        : build-dir ../build # will cause everything to be built into a
    sub-directory of /project/build
    ;

> I’ve been trying various things using alias’s and projects, but it
> just hasn’t panned out.  The examples available are pretty weak in the
> “multi-directory” department, sadly, so once I identify the correct
> path, I will definitely contribute an example.
>
>  
>
> Suggestions?
>
>  
>
> Cheers,
>
> --Benn
>

Hope this helps.

Phillip