BUG: mtrand cannot be imported on Cygwin

There is an issue that mtrand in numpy-1.22.x cannot be imported
because `PyInit_mtrand` is not exported on Cygwin.
https://cygwin.com/pipermail/cygwin/2022-January/250481.html

mtrand is generated from three sources, mtrand.c,
src/legacy/legacy-distributions.c, and src/distributions/distributions.c.
In numpy-1.21.x, there are no symbols with
a `__declspec(dllexport)` attribute in the source files.
On the other hand, in numpy-1.22.0,
the commit b797a0cb97a8a9e7e36962dc8c37c075967aa88b adds the attribute
to the symbols in src/distributions/distributions.c.
`PyInit_mtrand` is contained in mtrand.c, so the attribute is not added.

Cygwin's ld exports all symbols if there are no symbols
with the `__declspec(dllexport)` attribute.
Therefore, in numpy-1.21.x,
`PyInit_mtrand` without the attribute is also exported.
However, if there is even one symbol
with the `__declspec(dllexport)` attribute,
Cygwin's ld does not export symbols without the attribute.
Therefore, in numpy-1.22.0, `PyInit_mtrand`
without the attribute is not also exported.
https://sourceware.org/binutils/docs/ld/WIN32.html

This commit solves the issue by removing the unnecessary
`__declspec(dllexport)` attribute.

0 files changed, 0 insertions, 0 deletions