Fedora 42: Compile error: Boost: PyArray_Descr has no member named ‘elsize’

[radon-at-beeper]

The following error occurs when compiling on Fedora 42:

libs/python/src/numpy/dtype.cpp: In member function ‘int boost::python::numpy::dtype::get_itemsize() const’:
libs/python/src/numpy/dtype.cpp:101:83: error: ‘PyArray_Descr’ {aka ‘struct _PyArray_Descr’} has no member named ‘elsize’
  101 | int dtype::get_itemsize() const { return reinterpret_cast<PyArray_Descr*>(ptr())->elsize;}
      |                                                                                   ^~~~~~

The compilation command line is:

./build/fbcode_builder/getdeps.py build mvfst --verbose

Adding the --allow-system-packages argument makes no difference to the error that is reported, even if the boost-devel package is installed system-wide.

Notably: https://github.com/boostorg/boost version 1.89.0 compiles perfectly fine on the same system, using the same command-line options that are displayed in the log. However, version 1.83.0, which seems to be the specific version wanted by mvfst, does not compile, and exhibits the same error.