ENH Build with Ninja & Pass ccache variables to conda recipe (#705)

Changes:

- Enables `ninja` build system
- Exposes `ccache` environment variables to the conda build

These changes are required to allow `ccache` to function correctly and have a high cache hitrate during builds.

Authors:
  - Dillon Cullinan (@dillon-cullinan)

Approvers:
  - Jordan Jacobelli (@ethyling)
  - Keith Kraus (@kkraus14)
  - Mark Harris (@harrism)

URL: #705

Author: dillon-cullinan

ci/cpu/build.sh

@@ -5,9 +5,10 @@
 ######################################
 set -e
 
-# Set path and build parallel level
+# Set path, build parallel level and build generator
 export PATH=/opt/conda/bin:/usr/local/cuda/bin:$PATH
 export PARALLEL_LEVEL=${PARALLEL_LEVEL:-4}
+export CMAKE_GENERATOR="Ninja"
 
 # Set home to the job's workspace
 export HOME=$WORKSPACE

conda/recipes/librmm/meta.yaml

@@ -18,6 +18,13 @@ build:
     - CUDAHOSTCXX
     - PARALLEL_LEVEL
     - VERSION_SUFFIX
+    - CCACHE_DIR
+    - CCACHE_NOHASHDIR
+    - CCACHE_COMPILERCHECK
+    - CMAKE_GENERATOR
+    - CMAKE_C_COMPILER_LAUNCHER
+    - CMAKE_CXX_COMPILER_LAUNCHER
+    - CMAKE_CUDA_COMPILER_LAUNCHER
   run_exports:
     - {{ pin_subpackage("librmm", max_pin="x.x") }}