Let TriBITS handle MPI

Signed-off-by: Carl Pearson <[email protected]>

Author: cwpearson

CMakeLists.txt

@@ -68,6 +68,14 @@ set(KOKKOSCOMM_ENABLE_PERFTESTS ${KokkosComm_ENABLE_PERFTESTS} CACHE BOOL "" FOR
 set(KOKKOSCOMM_ENABLE_TESTS ${KokkosComm_ENABLE_TESTS} CACHE BOOL "" FORCE)
 set(KOKKOSCOMM_ENABLE_MPI ${KokkosComm_ENABLE_MPI} CACHE BOOL "" FORCE)
 
+if (KOKKOSCOMM_HAS_TRILINOS)
+  if (TPL_ENABLE_MPI)
+    if (NOT KOKKOSCOMM_ENABLE_MPI)
+      message(WARNING "TPL_ENABLE_MPI is set. Overriding KOKKOSCOMM_ENABLE_MPI to ON")
+      set(KOKKOSCOMM_ENABLE_MPI ON CACHE BOOL "" FORCE)
+    endif()
+  endif()
+endif()
 
 if (KOKKOSCOMM_HAS_TRILINOS)
   # Trilinos will "find" Kokkos and MPI

src/KokkosComm/CMakeLists.txt

@@ -17,8 +17,6 @@
 add_library(KokkosComm INTERFACE)
 add_library(KokkosComm::KokkosComm ALIAS KokkosComm)
 
-
-
 # Public headers
 target_sources(
   KokkosComm
@@ -115,8 +113,10 @@ kokkoscomm_check_and_add_compile_options(KokkosCommFlags -Wno-gnu-zero-variadic-
 # linked before CUDA and friends, so link MPI before Kokkos.
 # TODO_CMAKE: in CMake 3.31, we can use LINK_LIBRARIES_STRATEGY to explicitly ask CMake not to
 # reorder how libraries are linked. In the mean time, we have to just hope (?).
-if(KOKKOSCOMM_ENABLE_MPI)
-  target_link_libraries(KokkosComm INTERFACE MPI::MPI_CXX)
+if(NOT KOKKOSCOMM_HAS_TRILINOS)
+  if(KOKKOSCOMM_ENABLE_MPI)
+    target_link_libraries(KokkosComm INTERFACE MPI::MPI_CXX)
+  endif()
 endif()
 target_link_libraries(KokkosComm INTERFACE KokkosComm::KokkosCommFlags Kokkos::kokkos)