Re: [Qemu-devel] [PATCH] Makefile: Avoid explicit list of directories in clean target

[Stefan Hajnoczi]

On Tue, Jul 31, 2012 at 08:24:58AM -0600, Eric Blake wrote:
> On 07/31/2012 08:19 AM, Markus Armbruster wrote:
> > Peter Maydell <address@hidden> writes:
> > 
> >> Avoid having an explicit list of directories in the 'clean'
> >> target by using 'find' to remove all .o and .d files instead.
> >>
> 
> >>    rm -f qemu-options.def
> >> -  rm -f *.o *.d *.a *.lo $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* 
> >> *.pod *~ */*~
> >> +  find . -name '*.[od]' | xargs rm -f
> >> +  rm -f *.a *.lo $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* *.pod *~ */*~
> > 
> > Shit happens if you somehow manage to create a "mean" file name in the
> > build tree.  Sure you don't want to -print0 | xargs -0?
> 
> Except that 'find -print0' and 'xargs -0' are both GNU extensions, not
> available everywhere.  We may be requiring gmake and gcc, but are we
> also requiring GNU find?
> 
> The POSIX way to write this, without relying on extensions, is:
> 
> find . -name '*.[od]' -exec rm -f {} +
> 
> (although then you get into the arguments of whether 'find -exec {} +'
> is portable yet, even though it has now been required by POSIX for more
> than 4 years.)

This portable approach seems reasonable.  I have checked the find(1) man
page on: FreeBSD, OpenBSD, Solaris 11, Mac OS X.

Let's give find -exec + a shot.  If it breaks something then the folks
who care can provide a buildslave to ensure their host platform
continues to be supported in the future.

Stefan