Compile error on GPU

[stubbiali]

I'm trying to build the Python binding on Alps.Santis with GPU enabled, but I keep getting this error when compiling bindings/python/src/_pyghex/mpi_comm_shim.cpp:

/users/subbiali/.cache/uv/git-v0/checkouts/0537b1d158fcb24c/3b059c31/bindings/python/src/_pyghex/mpi_comm_shim.cpp:102:53: error: ambiguous template instantiation for 'struct
      pybind11::detail::initimpl::factory<pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>, pybind11::detail::void_type (*)(), pyghex::mpi_comm_shim(pybind11::object),
      pybind11::detail::void_type()>'
        102 |     mpi_comm.def(pybind11::init<>())
            |                                                     ^
        103 |         .def(pybind11::init([](pybind11::object o) { return mpi_comm_shim(o); }), "mpi_comm_obj"_a,
            |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      /users/subbiali/.cache/uv/builds-v0/.tmpUEkUnE/lib/python3.11/site-packages/pybind11/include/pybind11/detail/init.h:374:8: note: candidates are: 'template<class Func, class Return, class ...
      Args> struct pybind11::detail::initimpl::factory<Func, pybind11::detail::void_type (*)(), Return(Args ...), __remove_pointer(__remove_reference(pybind11::detail::void_type (*)()))> [with Func =
      pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>; Return = pyghex::mpi_comm_shim; Args = {pybind11::object}]'
        374 | struct factory<Func, void_type (*)(), Return(Args...)> {
            |        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      /users/subbiali/.cache/uv/builds-v0/.tmpUEkUnE/lib/python3.11/site-packages/pybind11/include/pybind11/detail/init.h:413:8: note:                 'template<class CFunc, class AFunc,
      class CReturn, class ... CArgs, class AReturn, class ... AArgs> struct pybind11::detail::initimpl::factory<CFunc, AFunc, CReturn(CArgs ...), AReturn(AArgs ...)> [with CFunc =
      pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>; AFunc = pybind11::detail::void_type (*)(); CReturn = pyghex::mpi_comm_shim; CArgs = {pybind11::object}; AReturn =
      pybind11::detail::void_type; AArgs = {}]'
        413 | struct factory<CFunc, AFunc, CReturn(CArgs...), AReturn(AArgs...)> {
            |        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      /users/subbiali/.cache/uv/git-v0/checkouts/0537b1d158fcb24c/3b059c31/bindings/python/src/_pyghex/mpi_comm_shim.cpp:102:53: error: invalid use of incomplete type 'struct
      pybind11::detail::initimpl::factory<pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>, pybind11::detail::void_type (*)(), pyghex::mpi_comm_shim(pybind11::object),
      pybind11::detail::void_type()>'
        102 |     mpi_comm.def(pybind11::init<>())
            |                                                     ^
        103 |         .def(pybind11::init([](pybind11::object o) { return mpi_comm_shim(o); }), "mpi_comm_obj"_a,
            |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      /users/subbiali/.cache/uv/builds-v0/.tmpUEkUnE/lib/python3.11/site-packages/pybind11/include/pybind11/detail/init.h:369:42: note: declaration of 'struct
      pybind11::detail::initimpl::factory<pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>, pybind11::detail::void_type (*)(), pyghex::mpi_comm_shim(pybind11::object),
      pybind11::detail::void_type()>'
        369 |           typename = function_signature_t<AFunc>>
            |                                          ^~~~~~~
      /users/subbiali/.cache/uv/builds-v0/.tmpUEkUnE/lib/python3.11/site-packages/pybind11/include/pybind11/pybind11.h: In instantiation of 'Ret pybind11::init(Func&&) [with Func =
      pyghex::register_mpi(pybind11::module&)::<lambda(object)>; Ret = detail::initimpl::factory<pyghex::register_mpi(pybind11::module&)::<lambda(object)>, detail::void_type (*)(),
      pyghex::mpi_comm_shim(object), detail::void_type()>]':
      /users/subbiali/.cache/uv/git-v0/checkouts/0537b1d158fcb24c/3b059c31/bindings/python/src/_pyghex/mpi_comm_shim.cpp:102:53:   required from here
        102 |     mpi_comm.def(pybind11::init<>())
            |                                                     ^
        103 |         .def(pybind11::init([](pybind11::object o) { return mpi_comm_shim(o); }), "mpi_comm_obj"_a,
            |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      /users/subbiali/.cache/uv/builds-v0/.tmpUEkUnE/lib/python3.11/site-packages/pybind11/include/pybind11/pybind11.h:2598:1: error: return type 'struct
      pybind11::detail::initimpl::factory<pyghex::register_mpi(pybind11::module&)::<lambda(pybind11::object)>, pybind11::detail::void_type (*)(), pyghex::mpi_comm_shim(pybind11::object),
      pybind11::detail::void_type()>' is incomplete
       2598 | Ret init(Func &&f) {
            | ^~~~

I'm using the uenv prgenv-gnu/25.6:v1 that comes with GCC 14.2.0 and NVIDIA 12.9.41.

The bindings build fine on CPU.

[msimberg]

I've bumped into this issue as well now and we should try to get it fixed, one way or another.

I think it's the same as this issue upstream on pybind11: pybind/pybind11#5565.

It's specifically triggered with GCC 14 and CUDA. GCC 13 compiles GHEX(/pybind11) just fine.