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

[Jakub Jelinek <jakub@redhat.com>]

On Thu, Dec 17, 2015 at 09:02:39AM +0100, Thomas Schwinge wrote:
> On Tue, 15 Dec 2015 17:44:59 +0100, I wrote:
> > On Wed, 9 Dec 2015 17:56:13 +0800, "Thomas Preud'homme" <thomas.preudhomme@arm.com> wrote:
> > > c-c++-common/attr-simd-3.c fails to compile on arm-none-eabi targets due to -fcilkplus needing -pthread which is not available for those targets. This patch solves this issue by adding a condition to the cilkplus effective target that compiling with -fcilkplus succeeds and requires cilkplus as an effective target for attr-simd-3.c testcase.
> > 
> > >         PR testsuite/68629
> > >         * lib/target-supports.exp (check_effective_target_cilkplus): Also
> > >         check that compiling with -fcilkplus does not give an error.
> > >         * c-c++-common/attr-simd-3.c: Require cilkplus effective target.
> > 
> > > --- 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
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.

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

	Jakub