EMAIL_REPLY.txt

Hi Colleen,

The issue is that RMM headers depend on CCCL (CUDA C++ Core Libraries) headers like `cuda/stream_ref` and `cuda/memory_resource`. These are header-only and need to be in the compiler's include path.

When using CMake with `find_package(rmm)`, CCCL is provided automatically. But when compiling directly with `hipcc`, CCCL headers must be available.

**Solution:**
CCCL headers need to be installed with hipMM and added to the module's CPATH. 

1. After installing hipMM, copy CCCL headers:
   ```bash
   cp -r $hipMM_build_dir/_deps/libhipcxx-src/include/cuda $hipMM_install_dir/include/
   ```

2. In the hipMM module file, add:
   ```tcl
   prepend-path CPATH $hipMM_install_dir/include
   ```

**What hipcc command should look like:**
Once CCCL is in CPATH (via module), Russell's command should work as-is:
```bash
hipcc test.cpp
```

If CCCL isn't in CPATH yet, explicitly add it:
```bash
hipcc -I$hipMM_install_dir/include test.cpp
```

**Why tests didn't catch this:**
Unit tests use CMake which automatically provides CCCL via the `CCCL::CCCL` target. Direct `hipcc` compilation doesn't have this automatic setup.

The "cuda" in the name is expected - CCCL provides CUDA-compatible headers that work with chipStar's HIP implementation.

Let me know if you need help setting up the installation or module configuration.