Re: [perf] make clean problematic bashism

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

On Wed, 2012-08-15 at 11:52 +0200, Wouter M. Koolen wrote:
> Dear perf maintainers,
> 
> I attempted to compile perf 3.5.1 without worrying about installing 
> dependencies first. The resulting error messages were quite helpful, and 
> led me to install a bunch of development libraries and flex.
> 
> Unfortunately, after installing flex the build still failed, even after 
> make clean.
> 
> The reason for this was a bunch of generated empty flex files in util/ 
> that were not removed by make clean. They are intended to be erased, 
> since the Makefile executes
> 
> rm -f util/*-{bison,flex}*
> 
> however, this command does not remove the files. I guess because {,} 
> alternatives are only special in bash but the makefile is run with some 
> other shell?

ISTR us getting a number of such patches, did we miss a site, acme?

> I got perf to compile now, but thought you would be interested to know 
> about this little problem.
> 
> With kind regards,
> 
> Wouter Koolen
> 
> 
> PS: as a side note: GNU make has the .DELETE_ON_ERROR: special target, 
> which removes the target file when its generating command fails. This 
> would have prevented my problem and sounds like a good idea in general. 
> Maybe perf could make use of this feature when on GNU make?

I don't think we build with anything but gnu make, mind sending a patch
implementing your suggestion?