second cmake build fails

[chinmay0301]

ubuntu@ubuntu:~/instant-ngp$ cmake --build build --config RelWithDebInfo -j
Consolidate compiler generated dependencies of target fmt
Consolidate compiler generated dependencies of target optix_program
Consolidate compiler generated dependencies of target glfw_objects
[  4%] Built target fmt
[  9%] Built target optix_program
[ 11%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/common.cu.o
[ 12%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/common_device.cu.o
[ 14%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/cutlass_mlp.cu.o
[ 15%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/loss.cu.o
[ 17%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/cpp_api.cu.o
[ 19%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/encoding.cu.o
[ 20%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/network.cu.o
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
[ 26%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/optimizer.cu.o
[ 47%] Built target glfw_objects
[ 49%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/object.cu.o
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
[ 50%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/reduce_sum.cu.o
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:76: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/common.cu.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:90: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/common_device.cu.o] Error 1
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:118: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/cutlass_mlp.cu.o] Error 1
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:132: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/encoding.cu.o] Error 1
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:104: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/cpp_api.cu.o] Error 1
[ 52%] Building CUDA object dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/fully_fused_mlp.cu.o
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:146: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/loss.cu.o] Error 1
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:160: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/network.cu.o] Error 1
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:188: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/optimizer.cu.o] Error 1
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:174: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/object.cu.o] Error 1
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:202: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/reduce_sum.cu.o] Error 1
nvcc fatal   : A single input file is required for a non-link phase when an outputfile is specified
make[2]: *** [dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/build.make:216: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/src/fully_fused_mlp.cu.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:288: dependencies/tiny-cuda-nn/CMakeFiles/tiny-cuda-nn.dir/all] Error 2
make: *** [Makefile:91: all] Error 2

Path to instant-ngp is /home/ubuntu/instant-ngp so there are no spaces to the path to instant-ngp as referenced in #39 or #198 .
The first cmake command succeeds, i.e. cmake . -B build , but the second one cmake --build build --config RelWithDebInfo -j fails with the error shown above.

[chinmay0301]

I solved it by running cmake command with -v flag, and then inspecting the command showed that the "gencode" flag had a trailing space. On removing that the build succeded.