"More than one tag given" error in Experimental::require()

[brian-kelley]

When the base policy (happens with team and range) passed to Kokkos::Experimental::require() has an explicit tag, there's an error in AnalyzePolicy saying multiple tag types were given (it always thinks the other one is void). A one-line example that replicates this:
auto pol = require(Kokkos::RangePolicy<Exec, TagType>(execInstance, 0, 100), Experimental::WorkItemProperty::HintLightWeight); where execInstance has type Exec, and TagType is anything other than void.

I have a branch "RequireTagIssue" in the fork git@github.com:brian-kelley/kokkos that builds this this as an example on whatever device(s) are enabled. It should work with generate_makefile or CMake but I had some trouble with a CMake build (include path was broken in all examples - Kokkos_Core.hpp wasn't found) so I can only promise it works with generate_makefile.

The error:

In file included from kokkos/core/src/Kokkos_ExecPolicy.hpp:51,
                 from kokkos/core/src/Kokkos_Threads.hpp:235,
                 from kokkos/core/src/Kokkos_Core.hpp:74,
                 from kokkos/example/require_tag_issue/main.cpp:47:
.../core/src/impl/Kokkos_AnalyzePolicy.hpp: In instantiation of ‘struct Kokkos::Impl::SetWorkTag<Kokkos::Impl::PolicyTraitsBase<Kokkos::Threads, Kokkos::Schedule<Kokkos::Static>, Tag1, Kokkos::IndexType<long unsigned int>, void, void, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<0> >, void>’:
.../core/src/impl/Kokkos_AnalyzePolicy.hpp:161:8:   recursively required from ‘struct Kokkos::Impl::AnalyzePolicy<Kokkos::Impl::PolicyTraitsBase<Kokkos::Threads, void, void, void, void, void, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<0> >, Kokkos::Schedule<Kokkos::Static>, Tag1, long unsigned int, void, Kokkos::LaunchBounds<0, 0>, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<1> >’
.../core/src/impl/Kokkos_AnalyzePolicy.hpp:161:8:   required from ‘struct Kokkos::Impl::AnalyzePolicy<Kokkos::Impl::PolicyTraitsBase<>, Kokkos::Threads, Kokkos::Schedule<Kokkos::Static>, Tag1, long unsigned int, void, Kokkos::LaunchBounds<0, 0>, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<1> >’
.../core/src/impl/Kokkos_AnalyzePolicy.hpp:226:8:   required from ‘struct Kokkos::Impl::PolicyTraits<Kokkos::Threads, Kokkos::Schedule<Kokkos::Static>, Tag1, long unsigned int, void, Kokkos::LaunchBounds<0, 0>, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<1> >’
.../core/src/Kokkos_ExecPolicy.hpp:93:7:   required from ‘class Kokkos::RangePolicy<Kokkos::Threads, Kokkos::Schedule<Kokkos::Static>, Tag1, long unsigned int, void, Kokkos::LaunchBounds<0, 0>, Kokkos::Experimental::WorkItemProperty::ImplWorkItemProperty<1> >’
.../example/require_tag_issue/main.cpp:80:24:   required from ‘void demonstrate() [with Device = Kokkos::Threads]’
.../example/require_tag_issue/main.cpp:101:34:   required from here
.../core/src/impl/Kokkos_AnalyzePolicy.hpp:113:57: error: static assertion failed: Kokkos Error: More than one work tag given
  113 |   static_assert(is_void<typename PolicyBase::work_tag>::value,

[crtrott]

Ok thanks for reporting this. Pretty sure this is a bug in the logic of require which modifies the template parameters of the policy ...

[crtrott]

I have the unit test written for RangePolicy and it fails to compile as expected.

[kyungjoo-kim]

@crtrott This needs to go into trilinos too.