[Windows] MINGW-W64 experimental build warnings with NumPy 2.2.6 on Python 3.14.2

[moizza-nasir]

Description

NumPy 2.2.6 installed via pip on Windows 64-bit shows MINGW-W64 experimental build warnings and runtime errors when used with OpenCV.

Environment

• OS: Windows 64-bit
• Python Version: 3.14.2
• NumPy Version: 2.2.6
• OpenCV Version: 4.12.0.88
• Installation Method: pip install numpy opencv-python
• Virtual Environment: Yes (venv)

Steps to Reproduce

1. Create virtual environment: python -m venv .venv
2. Activate: .venv\Scripts\Activate.ps1
3. Install: pip install opencv-python (installs numpy 2.2.6 as dependency)
4. Run simple OpenCV code:

import cv2 as cv
img = cv.imread("image.jpg")
cv.imshow('window', img)
cv.waitKey(0)
cv.destroyAllWindows()

Expected Behavior

NumPy and OpenCV should import and run without warnings.

Actual Behavior

Warning Message:

<frozen importlib._bootstrap>:491: Warning: Numpy built with MINGW-W64 on Windows 64 bits is experimental, and only available for testing. You are advised not to use it for production.
CRASHES ARE TO BE EXPECTED - PLEASE REPORT THEM TO NUMPY DEVELOPERS

Runtime Warnings:

C:\Python\.venv\Lib\site-packages\numpy\core\getlimits.py:225: RuntimeWarning: invalid value encountered in exp2
  epsneg_f128 = exp2(ld(-113))
C:\Python\.venv\Lib\site-packages\numpy\core\getlimits.py:226: RuntimeWarning: invalid value encountered in exp2
  tiny_f128 = exp2(ld(-16382))
C:\Python\.venv\Lib\site-packages\numpy\core\getlimits.py:240: RuntimeWarning: invalid value encountered in exp2
  eps=exp2(ld(-112)),
C:\Python\.venv\Lib\site-packages\numpy\core\getlimits.py:41: RuntimeWarning: invalid value encountered in nextafter
  self._smallest_subnormal = nextafter(
C:\Python\.venv\Lib\site-packages\numpy\core\getlimits.py:52: RuntimeWarning: invalid value encountered in log10
  self.precision = int(-log10(self.eps))

Additional Information

pip show numpy output:

Name: numpy
Version: 2.2.6
Location: c:\Python\.venv\Lib\site-packages
Requires:
Required-by: opencv-python

What I've Tried

• Reinstalling with --only-binary :all: flag
• Clearing pip cache: pip cache purge
• Force reinstall: pip install --force-reinstall numpy
• Downgrading to numpy 1.26.4 (causes dependency conflict with opencv 4.12)

Questions

1. Why is NumPy 2.2.6 on PyPI built with MINGW-W64 for Windows?
2. Is there an official Windows build available?
3. Should I downgrade to Python 3.11/3.12 or wait for fixes?
4. What's the recommended NumPy + OpenCV combination for Windows currently?

System Details

python --version
# Python 3.14.2

pip --version
# pip 25.3

pip list
# numpy         2.2.6
# opencv-python 4.12.0.88

Workaround Attempted

Tried using numpy==1.26.4 but got:

ERROR: opencv-python 4.12.0.88 requires numpy<2.3.0,>=2; python_version >= "3.9", 
but you have numpy 1.26.4 which is incompatible.

Any guidance would be appreciated!

[prangkiss]

i had same issue. so that i downgraded to 3.12.10 then it worked.

i don't know why but there is something issue when using numpy 2.2.6 with python 3.14.2?

[asmorkalov]

The code in the issue description is not related to OpenCV at all.