Support mkl-service in virtual environment out of the box

mkl/__init__.py

@@ -25,6 +25,8 @@
 
 import sys
 
+from . import _init_helper
+
 
 class RTLD_for_MKL:
     def __init__(self):
@@ -57,3 +59,5 @@ def __exit__(self, *args):
 
 from ._py_mkl_service import *
 from ._version import __version__
+
+del _init_helper

mkl/_init_helper.py

@@ -0,0 +1,42 @@
+# Copyright (c) 2025, Intel Corporation
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+#     * Redistributions of source code must retain the above copyright notice,
+#       this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+#     * Neither the name of Intel Corporation nor the names of its contributors
+#       may be used to endorse or promote products derived from this software
+#       without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import os
+import os.path
+import sys
+
+is_venv_win32 = (
+    sys.platform == "win32"
+    and sys.base_exec_prefix != sys.exec_prefix
+    and os.path.isfile(os.path.join(sys.exec_prefix, "pyvenv.cfg"))
+)
+
+if is_venv_win32:
+    # In Windows venv: add Library/bin to PATH for proper DLL loading
+    dll_dir = os.path.join(sys.exec_prefix, "Library", "bin")
+    if os.path.isdir(dll_dir):
+        os.add_dll_directory(dll_dir)
+
+del is_venv_win32