on windows generate a .dll then copy it

note: internally rules_cc do some stuff when extension is .so or .dll
BUT not if it's .pyd
see: https://github.com/search?q=repo%3Abazelbuild%2Frules_cc%20.dll&type=code

Author: Mizux

build_defs.bzl

@@ -84,7 +84,7 @@ def pybind_extension(
     )
 
     cc_binary(
-        name = name + ".pyd",
+        name = name + ".dll",
         copts = copts + PYBIND_COPTS + select({
             Label("@pybind11//:msvc_compiler"): [],
             "//conditions:default": ["-fvisibility=hidden"],
@@ -105,10 +105,18 @@ def pybind_extension(
         **kwargs
     )
 
+    copy_file(
+        name = name + "_copy_dll_to_pyd",
+        src = name + ".dll",
+        out = name + ".pyd",
+        testonly = kwargs.get("testonly"),
+        visibility = kwargs.get("visibility"),
+    )
+
     native.alias(
         name = name,
         actual = select({
-            "@platforms//os:windows": name + ".pyd",
+            "@platforms//os:windows": name + "_copy_dll_to_pyd",
             "//conditions:default": name + ".so",
         }),
         testonly = kwargs.get("testonly"),