bug#20843: 24.5; Profiler error: "Invalid sampling interval"

[Eli Zaretskii]

> Date: Sat, 20 Jun 2015 15:02:28 -0400
> From: Ken Brown <kbrown@cornell.edu>
> CC: 20843@debbugs.gnu.org
> 
> On 6/18/2015 4:57 AM, Eli Zaretskii wrote:
> >> From: Sebastien Vauban <sva-news@mygooglest.com>
> >> Date: Thu, 18 Jun 2015 10:37:02 +0200
> >>
> >> When trying to start the profiler under Cygwin Emacs 24.5, I get this:
> >>
> >> --8<---------------cut here---------------start------------->8---
> >> Debugger entered--Lisp error: (error "Invalid sampling interval")
> >>    profiler-cpu-start(1000000)
> >>    profiler-start(cpu)
> >>    call-interactively(profiler-start record nil)
> >
> > Can you step with GDB into setup_cpu_timer, and see what goes wrong
> > there?  I suspect this portions:
> [...]
> 
> No, the problem is that Cygwin's setitimer supports only ITIMER_REAL, so 
> the call to setitimer(ITIMER_PROF,...) in profiler.c:315 fails.

Then I guess the configure-time test for setitimer should also test
for ITIMER_PROF.  Also, the diagnostics should be improved, as the
wording is misleading in that case.