Re: how well does multi-arch build handle recursive building?

[Robert P. J. Day]

On Fri, 12 May 2006, Greg Chicares wrote:

> On 2006-5-11 18:23 UTC, Robert P. J. Day wrote:
> >   at the moment, i'm using paul's multi-architecture build described
> > here:
> >
> > http://make.paulandlesley.org/multi-arch.html
> >
> > successfully for simple builds for which all of the source files
> > are in a single directory.  (i'm not actually doing
> > multi-architecture builds, i'm just using that technique to build
> > the results in a remote directory.  same difference, obviously.)
>
> I use that technique in day-to-day production, for multiple
> compilers, placing object and other binary files in compiler-
> specific directories. Source files are scattered here and there, but
> vpath means I don't need to worry about that.
>
> > so how well does that technique extend to recursive builds?
>
> It applies a single makefile recursively over directories.

but *how*?  i understand well enough how the multi-arch approach works
with all of the source files in a single remote directory that can be
referenced via vpath.  (in fact, it's just as easy to see how that can
work if the sources are scattered across *several* directories, as
long as the objects are being constructed in a single build
directory.)

but how does the multi-arch approach work if one tries to extend it to
a recursive make structure?  you know -- the kind where part of the
top-level makefile defines a number of SUBDIRS and reinvokes make with
"make -C" for each of those SUBDIRS?

if you're trying to emulate the original recursive build, that would
seem to mean that, for each sub-directory you move into, you need to
redefine vpath to the corresponding sub-directory for the sources, no?

do you have an actual example of the makefiles you're using to show
how you're doing this recursive build?

rday