[package] opencv/4.9: opencv cannot be built with clang-cl + dynamic runtime

[Jimbopython]

Description

When building with clang-cl and dynamic runtime, opencv is actually built with static runtime. BUILD_WITH_STATIC_CRT is on by default in opencv cmake (if MSVC). Clang-cl identifies as MSVC, which is why it's on by default. The conan recipe makes the following check:

if is_msvc(self):
    tc.variables["BUILD_WITH_STATIC_CRT"] = is_msvc_static_runtime(self)

But is_msvc evaluates to false, as it checks for the compiler actually being the visual studio MSVC. BUILD_WITH_STATIC_CRT is not set in the resulting toolchain file from conan.

Package and Environment Details

• Package Name/Version: opencv/4.9.0
• Operating System+version: Windows 11
• Compiler+version: Clang-CL 16
• Docker image: -
• Conan version: conan 1.64.0
• Python version: Python 3.11.3

Conan profile

[settings] os=Windows arch=x86_64 compiler=clang compiler.version=16 compiler.cppstd=20 compiler.runtime=dynamic compiler.runtime_type=Release compiler.runtime_version=v143

[conf] tools.cmake.cmaketoolchain:generator=Visual Studio 17

Steps to reproduce

conan install opencv/4.9.0@ -r conancenter --build -pr:b dummy -pr:h dummy -s:h build_type=Release -o shared=False -o contrib=False -o contrib_freetype=False -o contrib_sfm=False -o parallel=False -o with_ipp=False -o with_ade=False -o with_jpeg2000=False -o with_openexr=False -o with_eigen=False -o with_webp=False -o with_quirc=False -o with_cuda=False -o with_cublas=False -o with_cufft=False -o with_cudnn=False -o with_ffmpeg=False -o with_imgcodec_hdr=False -o with_imgcodec_pfm=False -o with_imgcodec_pxm=False -o with_imgcodec_sunraster=False -o dnn=False -o dnn_cuda=False -o cuda_arch_bin=False -o cpu_baseline=None -o cpu_dispatch=None -o nonfree=False -o with_flatbuffers=False -o with_protobuf=False -o with_tesseract=False -o with_opencl=False -o with_jpeg=False -o with_png=False -o with_tiff=False -o dnn=False -o gapi=False -o highgui=False -o imgcodecs=False -o ml=False -o objdetect=False -o photo=False -o stitching=False -o video=False -o videoio=False -o flann=False -o calib3d=False -o features2d=False -o imgproc=True

Logs

conan_opencv.log

[SpaceIm]

Yes... It comes from lack of proper helper in conan allowing to deduce clang flavor on Windows based on conan profile.

[SpaceIm]

Could you give a try to https://github.com/conan-io/conan-center-index/pull/24071?