MAINT: FFT pybind11 fixups

* remove the pybind11 version exclusion from Windows
Meson job in GitHub actions

* pin pybind11 to version `2.10.1` in `pyproject.toml`
out of an abundance of caution re: recent issues with
`2.10.2` (which has since been yanked from PyPI)

* small adjustment to `pypocketfft.cxx` to defened
against the segfault that occurs with pybind11 `2.10.2`
(arguably not a bug, but safer way to initialize here)

.github/workflows/windows.yml

@@ -46,7 +46,7 @@ jobs:
           gfortran --version
       - name: pip-packages
         run: |
-          pip install numpy==1.22.2 cython "pybind11!=2.10.2" pythran meson ninja pytest pytest-xdist pytest-timeout pooch
+          pip install numpy==1.22.2 cython pybind11 pythran meson ninja pytest pytest-xdist pytest-timeout pooch
       - name: openblas-libs
         run: |
           # Download and install pre-built OpenBLAS library

pyproject.toml

@@ -12,7 +12,9 @@ build-backend = 'mesonpy'
 requires = [
     "meson-python>=0.11.0,<0.12.0",
     "Cython>=0.29.32,<3.0",
-    "pybind11>=2.10.0,!=2.10.2,<2.11.0",
+    # conservatively avoid issues from
+    # https://github.com/pybind/pybind11/issues/4420
+    "pybind11==2.10.1",
     "pythran>=0.12.0,<0.13.0",
     # `wheel` is needed for non-isolated builds, given that `meson-python`
     # doesn't list it as a runtime requirement (at least in 0.5.0)

scipy/fft/_pocketfft/pypocketfft.cxx

@@ -37,7 +37,6 @@ using clong = std::complex<ldbl_t>;
 using f32 = float;
 using f64 = double;
 using flong = ldbl_t;
-auto None = py::none();
 
 shape_t copy_shape(const py::array &arr)
   {
@@ -717,6 +716,8 @@ PYBIND11_MODULE(pypocketfft, m)
   {
   using namespace pybind11::literals;
 
+  auto None = py::none();
+
   m.doc() = pypocketfft_DS;
   m.def("c2c", c2c, c2c_DS, "a"_a, "axes"_a=None, "forward"_a=true,
     "inorm"_a=0, "out"_a=None, "nthreads"_a=1);