Re: [PATCH] perf tools: Don't use brace expansion.

[Bernd Petrovitsch <bernd@petrovitsch.priv.at>]

On Mon, 2010-08-16 at 12:29 -0300, Arnaldo Carvalho de Melo wrote:
> Em Mon, Aug 16, 2010 at 04:54:38PM +0200, Bernd Petrovitsch escreveu:
> > On Mon, 2010-08-16 at 16:30 +0200, Peter Zijlstra wrote:
> > > On Mon, 2010-08-16 at 16:09 +0200, Bernd Petrovitsch wrote:
> > > > > -$(shell sh -c 'mkdir -p $(OUTPUT)scripts/{perl,python}/Perf-Trace-Util/' 2> /dev/null)
> > > > > -$(shell sh -c 'mkdir -p $(OUTPUT)util/{ui/browsers,scripting-engines}/' 2> /dev/null)
> 
> > > > The other solution is to use standard-make features like in
> > > > mkdir -p $(foreach d,ui/browsers scripting-engines,$(OUTPUT)util/$(d)/) 2> /dev/null
> 
> > > > Is there actually a specific reason for the 
> > > > $(shell sh -c '...')
> > > > around?
> > > > It looks superflous.
> 
> > > I think the reason is is that nobody who touched that file really knew
> > > make all that well. Your version looks fine to me.
> 
> > Ah, the reason is that they are not part of a rule but on the top-level
> > (and thus always executed).
> 
> So it worked by luck! /me runs :-P

IMHO it's not really luck with GNU-make.

> More seriously, so there is a reason for that to be like that and you're
> not aware of any other shorter or more convenient way of achieving that

One (obvious) alternative is to have rules triggering on the
non-existence of these directories.

> goal, right?

Hmm, I'm not a "perf person". Which are the sufficient use-cases/tests
that one can do to play around with the Makefile?

`make -C tools/perf` is probably not enough.

Any hints anyone?

	Bernd
-- 
Bernd Petrovitsch                  Email : bernd@petrovitsch.priv.at
                     LUGA : http://www.luga.at