Hi!
On Tue, 23 Feb 2016 08:37:07 +0100, Tom de Vries <[email protected]> wrote:
> On 22/02/16 19:07, Ilya Verbin wrote:
> > 2016-02-22 18:13 GMT+03:00 Thomas Schwinge<[email protected]>:
> >> >On Sat, 20 Feb 2016 13:54:20 +0300, Ilya Verbin<[email protected]> wrote:
> >>> >>On Fri, Feb 19, 2016 at 15:53:08 +0100, Jakub Jelinek wrote:
> >>>> >> >On Wed, Feb 10, 2016 at 08:19:34PM +0300, Ilya Verbin wrote:
> >>>>> >> > >This patch adds crtoffload{begin,end}.o to all -fopenmp programs,
> >>>>> >> > >if they exist.
> >>> >>Thomas, could you please test it using nvptx
> >> >
> >> >It mostly;-) works. With nvptx offloading enabled (which you don't
> >> >have, do you?), I'm seeing one test case regress:
> >> >
> >> > [-PASS:-]{+FAIL:+}
> >> > libgomp.oacc-c/../libgomp.oacc-c-c++-common/parallel-dims-2.c
> >> > -DACC_DEVICE_TYPE_nvidia=1 -DACC_MEM_SHARED=0 (test for errors, line 9)
> >> > [-PASS:-]{+FAIL:+}
> >> > libgomp.oacc-c/../libgomp.oacc-c-c++-common/parallel-dims-2.c
> >> > -DACC_DEVICE_TYPE_nvidia=1 -DACC_MEM_SHARED=0 (test for errors, line 13)
> >> > PASS: libgomp.oacc-c/../libgomp.oacc-c-c++-common/parallel-dims-2.c
> >> > -DACC_DEVICE_TYPE_nvidia=1 -DACC_MEM_SHARED=0 (test for excess errors)
> >> > [-PASS:-]{+FAIL:+}
> >> > libgomp.oacc-c/../libgomp.oacc-c-c++-common/parallel-dims-2.c
> >> > -DACC_DEVICE_TYPE_nvidia=1 -DACC_MEM_SHARED=0 execution test
> >> >
> >> >(Same for C++.) That testcase, just recently added by Tom in r233237
> >> >"Handle -fdiagnostics-color in lto", specifies 'dg-additional-options
> >> >"-flto -fno-use-linker-plugin"'. Is that now an unsupported
> >> >combination/configuration? (I have not yet looked in detail, but it
> >> >appears as if the offloading compilers are no longer being run for
> >> >-fno-use-linker-plugin.)
> > Yes, it's really hard to fix the "lto + non-lto objects" issue for
> > no-use-linker-plugin LTO path. In this patch lto-plugin prepares a
> > list of objects files with offloading and passes it to lto-wrapper, so
> > I believe we should consider offloading without lto-plugin as
> > unsupported. I'll update wiki when the patch will be committed.
Aha, I see. I guess there's no point in keeping offloading supported for
the -fno-lto (default) with -fno-use-linker-plugin configuration?
Ilya, then please remove
libgomp/testsuite/libgomp.oacc-c-c++-common/parallel-dims-2.c as part of
your patch, unless Tom thinks it should be changed to a -flto test, but
without -fno-use-linker-plugin?
> Shouldn't we error (or at least warn) then if we compile a file
> containing an offload construct with fopenacc/fopenmp and
> -fno-use-linker-plugin?
Yes, that makes sense to me, too. (Note that, as I understand it,
-fno-use-linker-plugin may also be the default for certain GCC
configurations...) Aside from spec stuff in gcc/gcc.c relating to
LINK_PLUGIN_SPEC, I see there's some code in
gcc/gcc.c:driver::maybe_run_linker evaluating the three possible values
of HAVE_LTO_PLUGIN, but I have not yet thought about how and where to
conditionalize the diagnostic if attempting to do offloading in an
unsupported (-fno-use-linker-plugin) configuration.
Grüße
Thomas
