Wire-Cell CUDA

This package is a mostly empty place holder for now. In the future it may provide Wire-Cell Toolkit components that depend on CUDA.

For now, it tests the Wire-Cell build system to optionally work with CUDA.

A minimal test build with CUDA goes something like:

$ NVCCFLAGS="-O3" ./wcb configure --with-cuda=/path/to/cuda [...usual...]
$ ./wcb --target=test_simple_cuda -j1 -vv

[... check nvcc command is as desired ...]

execution summary 
  tests that pass 1/1 
    /home/bviren/dev/wctcuda/build/cuda/test_simple_cuda 
  tests that fail 0/1 
'build' finished successfully (0.829s)