Revert "refactor(cc): remove user_link_flags  for Windows and simplify current_py_cc_libs"

This reverts commit 71df3253c88c638bfc46bcc8131a9789caf9d261.

python/private/cc/py_extension_macro.bzl

diff --git a/python/private/cc/py_extension_macro.bzl b/python/private/cc/py_extension_macro.bzl
index 9938697..7514b3f 100644
--- a/python/private/cc/py_extension_macro.bzl
+++ b/python/private/cc/py_extension_macro.bzl
@@ -140,18 +140,25 @@
     # - On macOS, Apple's ld64 linker requires '-undefined dynamic_lookup' so CPython
     #   C-API symbols (e.g. PyModule_Create) remain unresolved at link time and are
     #   dynamically resolved at runtime when CPython loads the shared library (.so).
-    # - On Windows, link.exe automatically receives the CPython import library (.lib)
-    #   via CcInfo in deps.
+    # - On Windows, link.exe receives the CPython import library (.lib) passed via
+    #   current_py_cc_libs.
     effective_user_link_flags = (user_link_flags or linkopts or []) + select({
         "@platforms//os:macos": ["-undefined", "dynamic_lookup"],
         "@platforms//os:osx": ["-undefined", "dynamic_lookup"],
+        "@platforms//os:windows": ["$(locations @rules_python//python/cc:current_py_cc_libs)"],
         "//conditions:default": [],
     })
     csl_kwargs["user_link_flags"] = effective_user_link_flags
 
+    csl_additional_linker_inputs = select({
+        "@platforms//os:windows": ["@rules_python//python/cc:current_py_cc_libs"],
+        "//conditions:default": [],
+    })
+
     cc_shared_library(
         name = csl_name,
         deps = final_csl_deps,
+        additional_linker_inputs = csl_additional_linker_inputs,
         dynamic_deps = dynamic_deps,
         visibility = ["//visibility:private"],
         **csl_kwargs

python/private/current_py_cc_libs.bzl

diff --git a/python/private/current_py_cc_libs.bzl b/python/private/current_py_cc_libs.bzl
index 485e1d2..58ab4b1 100644
--- a/python/private/current_py_cc_libs.bzl
+++ b/python/private/current_py_cc_libs.bzl
@@ -18,7 +18,39 @@
 
 def _current_py_cc_libs_impl(ctx):
     py_cc_toolchain = ctx.toolchains["//python/cc:toolchain_type"].py_cc_toolchain
-    return list(py_cc_toolchain.libs.providers_map.values())
+    providers = [p for p in py_cc_toolchain.libs.providers_map.values() if not hasattr(p, "data_runfiles")]
+    default_runfiles = None
+    data_runfiles = None
+    files = []
+    for p in py_cc_toolchain.libs.providers_map.values():
+        if hasattr(p, "data_runfiles"):
+            default_runfiles = p.default_runfiles
+            data_runfiles = p.data_runfiles
+
+    cc_infos = [p for p in py_cc_toolchain.libs.providers_map.values() if hasattr(p, "linking_context")]
+    if cc_infos:
+        cc_info = cc_infos[0]
+        for input in cc_info.linking_context.linker_inputs.to_list():
+            for lib in input.libraries:
+                if lib.static_library:
+                    files.append(lib.static_library)
+                if lib.interface_library:
+                    files.append(lib.interface_library)
+                elif lib.dynamic_library:
+                    files.append(lib.dynamic_library)
+
+    # On Windows MSVC, user_link_flags passes $(locations @rules_python//python/cc:current_py_cc_libs)
+    # to link.exe. MSVC link.exe accepts import libraries (.lib) but fails with
+    # LNK1107 if passed raw DLL binaries (.dll). We filter out .dll files so
+    # DefaultInfo.files only contains linkable library files (.lib / .a).
+    link_files = [f for f in files if not f.path.endswith(".dll")]
+
+    providers.append(DefaultInfo(
+        files = depset(link_files),
+        default_runfiles = default_runfiles,
+        data_runfiles = data_runfiles,
+    ))
+    return providers
 
 current_py_cc_libs = rule(
     implementation = _current_py_cc_libs_impl,