QT5+opencv4.1 编译 踩坑

参考文章：

cmake 配置参考见以下文章

https://wiki.qt.io/How_to_setup_Qt_and_openCV_on_Windows

https://blog.huihut.com/2017/12/03/CompiledOpenCVRunInQt/

编译过程中遇到的问题：

1.CMP0083 PIE policy warnings for executables are noisy

这个问题主要是因为cmake版本问题，cmake 3.14会有这个问题，详情https://gitlab.kitware.com/cmake/cmake/issues/18955。

切换成最新版的cmake 3.15解决。https://cmake.org/files/v3.15/

2.‘D3D11_TEXTURE2D_DESC’ was not declared in this scope 错误

在cmake config 中可以关闭 WITH_OPENCL_D3D11_NV 这个选项（默认是开的），然后重新 Configure-Generate-mingw32-make。

参考https://blog.csdn.net/huihut/article/details/81317102 第五点。

3.file not recognized,recipe for target failed

有两种情况：

第一种情况：Python2版成功，Python3版失败

第二种情况：只有Python3，仍然失败

先取消选中 Build_opencv_python3，后面用到再重新configure

参考：（这篇文章概括的比较全面，强烈推荐）

https://blog.csdn.net/yl_best/article/details/89190142#Issue%237%3APython3%E7%89%88%E7%BC%96%E8%AF%91%E5%A4%B1%E8%B4%A5

4.CMake Error: CMake was unable to find a build program corresponding to "MinGW Makefiles". CMAKE_MAK

CMake Error: CMake was unable to find a build program corresponding to "MinGW Makefiles". CMAKE_MAKE_PROGRAM is not set. You probably need to select a different build tool.

将CMAKE_MAKE_PROGRAM项后面的路径设置为Qt安装路径下的路径如下所示：MinGW/bin/mingw32-make.exe，重新点击Configure，问题解决！

参考：https://blog.csdn.net/u010189457/article/details/54957309/