RE: [PATCH, testsuite] Fix PR68629: attr-simd-3.c failure on arm-none-eabi targets

["Thomas Preud'homme" <thomas.preudhomme@foss.arm.com>]

Hi,

> From: Jakub Jelinek [mailto:jakub@redhat.com]
> Sent: Thursday, December 17, 2015 4:26 PM
> > >
> > > > --- a/gcc/testsuite/lib/target-supports.exp
> > > > +++ b/gcc/testsuite/lib/target-supports.exp
> > > > @@ -1432,7 +1432,12 @@ proc check_effective_target_cilkplus { } {
> > > >      if { [istarget avr-*-*] } {
> > > >  	return 0;
> > > >      }
> > > > -    return 1
> > > > +    return [ check_no_compiler_messages_nocache
> fcilkplus_available executable {
> > > > +	#ifdef __cplusplus
> > > > +	extern "C"
> > > > +	#endif
> > > > +	    int dummy;
> > > > +	} "-fcilkplus" ]
> > > >  }
> 
> That change has been obviously bad.  If anything, you want to make it
> compile time only, i.e. check_no_compiler_messages_nocache
> fcilkplus_available assembly

Indeed, I failed to parse the space and didn't realize the kind of testing could be selected.

> Just look at cilk-plus.exp:
> It checks check_effective_target_cilkplus, and performs lots of tests if it
> it returns true, and then checks check_libcilkrts_available and performs
> further tests.
> So, if any use of -fcilkplus fails on your target, then putting it
> into check_effective_target_cilkplus is fine, you won't lose any Cilk+
> testing that way.  Otherwise, if it is conditional say only some constructs,
> say array notation is fine, but _Cilk_for is not, then even that is wrong.

Ok. When I saw the very small list of target for which the condition returned true, I thought the goal was only to check if the target *could* support cilkplus and that actual support was tested by cilk-plus.exp. I'll revert this commit and prepare a patch to add arm in that list.

> 
> In any case, IMHO the attr-simd-3.c test just should be moved into
> c-c++-common/cilk-plus/SE/ directory.

That was my thought initially but then I changed my mind, thinking that the test was placed there for a reason. I'll prepare a third patch to do that.

My apologize for the breakage.

Best regards,

Thomas