This PR suggests a way to resolve the error of `unsupported Microsoft Visual Studio version!` in INSTALL.md.
Adding `-allow-unsupported-compiler` argument for the `nvcc` worked.
Editing [setup.py](https://github.com/facebookresearch/segment-anything-2/blob/main/setup.py) is required to add the `-allow-unsupported-compiler` argument for `nvcc`.
```python
def get_extensions():
srcs = ["sam2/csrc/connected_components.cu"]
compile_args = {
"cxx": [],
"nvcc": [
"-DCUDA_HAS_FP16=1",
"-D__CUDA_NO_HALF_OPERATORS__",
"-D__CUDA_NO_HALF_CONVERSIONS__",
"-D__CUDA_NO_HALF2_OPERATORS__",
"-allow-unsupported-compiler" # Add this argument
],
}
ext_modules = [CUDAExtension("sam2._C", srcs, extra_compile_args=compile_args)]
return ext_modules
```
In this PR, we make it optional to build the SAM 2 CUDA extension, in observation that many users encounter difficulties with the CUDA compilation step.
1. During installation, we catch build errors and print a warning message. We also allow explicitly turning off the CUDA extension building with `SAM2_BUILD_CUDA=0`.
2. At runtime, we catch CUDA kernel errors from connected components and print a warning on skipping the post processing step.
We also fall back to the all available kernels if the Flash Attention kernel fails.
