[bevdet_vendor] Cuda build error

[felixf4xu]

Hi,

I had some errors when build the project of bevdet_vendor.

The recommend environment is:

CUDA 11.8
cuDNN 8.6.0
TensorRT 8.5.2.2

My environment is:

-- Found CUDA: /usr/local/cuda (found version "11.8")
-- Found CUDNN: /usr/lib/x86_64-linux-gnu/libcudnn.so (found version "8.6.0")
-- Found TENSORRT: /usr/include/x86_64-linux-gnu (found version "8.5.3")

So if it's the environment difference, the only difference is TensorRT 8.5.2.2 and "8.5.3", which I think does not matter.

The issue is about this code:

*out_ptr_NCHW += static_cast<T2>(inp_ptr_NC[iy_nw * out_sH + ix_nw * out_sW]) * nw;

the error message is like this:

/src/universe/external/bevdet_vendor/src/alignbev_plugin.cu(75): error: more than one conversion function from "__half" to a built-in type applies:
function "__half::operator float() const"
/usr/local/cuda/include/cuda_fp16.hpp(204): here
function "__half::operator short() const"
/usr/local/cuda/include/cuda_fp16.hpp(222): here
function "__half::operator unsigned short() const"
/usr/local/cuda/include/cuda_fp16.hpp(225): here
function "__half::operator int() const"
/usr/local/cuda/include/cuda_fp16.hpp(228): here
function "__half::operator unsigned int() const"
/usr/local/cuda/include/cuda_fp16.hpp(231): here
function "__half::operator long long() const"
/usr/local/cuda/include/cuda_fp16.hpp(234): here
function "__half::operator unsigned long long() const"
/usr/local/cuda/include/cuda_fp16.hpp(237): here
function "__half::operator __nv_bool() const"
/usr/local/cuda/include/cuda_fp16.hpp(241): here
detected during instantiation of "void align_bev_kernel(int, const T1 *, const float *, T2 *, TensorDesc) [with T1=__half, T2=__half]"

The error happens when T1=__half, T2=__half.

I have fixed it like this:

*out_ptr_NCHW = static_cast<T2>(static_cast<float>(*out_ptr_NCHW) + static_cast<float>(inp_ptr_NC[iy_nw * out_sH + ix_nw * out_sW]) * static_cast<float>(nw));

[felixf4xu]

https://github.com/autowarefoundation/bevdet_vendor does not allow issue report, so I create the discussion here for search/discussion for anyone who happens to have a similar issue.

[felixf4xu]

autowarefoundation/bevdet_vendor#2