Undefined reference to get_complex_dtype<256>

In src/numpy/dtype.cpp, the definition of get_float_dtype < LONGDOUBLE > and get_complex_dtype < 2 * LONGDOUBLE > lacks BOOST_NUMPY_DECL.

Output of libs/python/test:
capture-output ../bin.v2/libs/python/test/numpy\~dtype.test/gcc-10/release/debug-symbols-on/pch-off/python-3.9/threading-multi/visibility-hidden/numpy\~dtype
====== BEGIN OUTPUT ======
Traceback (most recent call last):
File "/root/rpmbuild/BUILD/boost_1_78_0/status/../libs/python/test/numpy/dtype.py", line 8, in
import dtype_ext
ImportError: /root/rpmbuild/BUILD/boost_1_78_0/bin.v2/libs/python/test/numpy~dtype.test/gcc-10/release/debug-symbols-on/pch-off/python-3.9/threading-multi/visibility-hidden/dtype_ext.so: undefined symbol: _ZN5boost6python5numpy6detail17get_complex_dtypeILi256EEENS1_5dtypeEv

EXIT STATUS: 1
====== END OUTPUT ======

Start in src/numpy/dtype.cpp, where the LONGDOUBLE and 2 * LONGDOUBLE dtype definitions are mentioned. Run the libs/python/test/numpy/dtype.py test or the reported libs/python/test command and inspect the generated extension's symbol error. Done means the dtype test imports successfully without the undefined get_complex_dtype<256> reference.

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