Have Kokkos TriBITS build set compiler options as target properties (t…

…rilinos#11545)

With the TriBITS modernization refactoring (TriBITSPub/TriBITS#299) and the
generalizated handling of intenral and external packages
(TriBITSPub/TriBITS#63), we need packages like Kokkos to set critical compiler
options as target properties so that they will be exported in the generated
IMPORTED targets of the Kokkos<Subpkg>Targets.cmake file.

This is needed, for example, to pass some critical compiler flags from the
pre-installed Kokkos to downstream CMake configures of KokkosKernels and the
rest of Trilinos (see trilinos#11545).

packages/kokkos/CMakeLists.txt

@@ -126,6 +126,8 @@ IF(NOT KOKKOS_HAS_TRILINOS)
           FORCE)
     ENDIF()
   ENDIF()
+ELSE()
+  SET(KOKKOS_COMPILE_LANGUAGE CXX)
 ENDIF()
 
 IF (NOT CMAKE_SIZEOF_VOID_P)

packages/kokkos/cmake/kokkos_tribits.cmake

@@ -353,6 +353,7 @@ MACRO(KOKKOS_INSTALL_ADDITIONAL_FILES)
           DESTINATION ${KOKKOS_HEADER_DIR})
 ENDMACRO()
 
+
 FUNCTION(KOKKOS_SET_LIBRARY_PROPERTIES LIBRARY_NAME)
   CMAKE_PARSE_ARGUMENTS(PARSE
     "PLAIN_STYLE"
@@ -441,6 +442,7 @@ FUNCTION(KOKKOS_SET_LIBRARY_PROPERTIES LIBRARY_NAME)
   ENDIF()
 ENDFUNCTION()
 
+
 FUNCTION(KOKKOS_INTERNAL_ADD_LIBRARY LIBRARY_NAME)
   CMAKE_PARSE_ARGUMENTS(PARSE
     "STATIC;SHARED"
@@ -503,19 +505,11 @@ FUNCTION(KOKKOS_ADD_LIBRARY LIBRARY_NAME)
     # preserving the directory structure, e.g. impl
     # If headers got installed in both locations, it breaks some
     # downstream packages
-    TRIBITS_ADD_LIBRARY(${LIBRARY_NAME} ${PARSE_UNPARSED_ARGUMENTS})
-    #Stolen from Tribits - it can add prefixes
-    SET(TRIBITS_LIBRARY_NAME_PREFIX "${${PROJECT_NAME}_LIBRARY_NAME_PREFIX}")
-    SET(TRIBITS_LIBRARY_NAME ${TRIBITS_LIBRARY_NAME_PREFIX}${LIBRARY_NAME})
-    #Tribits has way too much techinical debt and baggage to even
-    #allow PUBLIC target_compile_options to be used. It forces C++ flags on projects
-    #as a giant blob of space-separated strings. We end up with duplicated
-    #flags between the flags implicitly forced on Kokkos-dependent and those Kokkos
-    #has in its public INTERFACE_COMPILE_OPTIONS.
-    #These do NOT get de-deduplicated because Tribits
-    #creates flags as a giant monolithic space-separated string
-    #Do not set any transitive properties and keep everything working as before
-    #KOKKOS_SET_LIBRARY_PROPERTIES(${TRIBITS_LIBRARY_NAME} PLAIN_STYLE)
+    TRIBITS_ADD_LIBRARY(${LIBRARY_NAME} ${PARSE_UNPARSED_ARGUMENTS}
+      ADDED_LIB_TARGET_NAME_OUT  ${LIBRARY_NAME}_TARGET_NAME )
+    IF (PARSE_ADD_BUILD_OPTIONS)
+      KOKKOS_SET_LIBRARY_PROPERTIES(${${LIBRARY_NAME}_TARGET_NAME})
+    ENDIF()
   ELSE()
     # Forward the headers, we want to know about all headers
     # to make sure they appear correctly in IDEs
@@ -527,15 +521,24 @@ FUNCTION(KOKKOS_ADD_LIBRARY LIBRARY_NAME)
   ENDIF()
 ENDFUNCTION()
 
+
 FUNCTION(KOKKOS_ADD_INTERFACE_LIBRARY NAME)
-IF (KOKKOS_HAS_TRILINOS)
-  TRIBITS_ADD_LIBRARY(${NAME} ${ARGN})
-ELSE()
-  ADD_LIBRARY(${NAME} INTERFACE)
-  KOKKOS_INTERNAL_ADD_LIBRARY_INSTALL(${NAME})
-ENDIF()
+  IF (KOKKOS_HAS_TRILINOS)
+    TRIBITS_ADD_LIBRARY(${NAME} ${ARGN})
+  ELSE()
+    CMAKE_PARSE_ARGUMENTS(PARSE
+      ""
+      ""
+      "HEADERS;SOURCES"
+      ${ARGN}
+      )
+
+    ADD_LIBRARY(${NAME} INTERFACE)
+    KOKKOS_INTERNAL_ADD_LIBRARY_INSTALL(${NAME})
+  ENDIF()
 ENDFUNCTION()
 
+
 FUNCTION(KOKKOS_LIB_INCLUDE_DIRECTORIES TARGET)
   IF(KOKKOS_HAS_TRILINOS)
     #ignore the target, tribits doesn't do anything directly with targets
@@ -549,13 +552,8 @@ FUNCTION(KOKKOS_LIB_INCLUDE_DIRECTORIES TARGET)
 ENDFUNCTION()
 
 FUNCTION(KOKKOS_LIB_COMPILE_OPTIONS TARGET)
-  IF(KOKKOS_HAS_TRILINOS)
-    #don't trust tribits to do this correctly
-    KOKKOS_TARGET_COMPILE_OPTIONS(${TARGET} ${ARGN})
-  ELSE()
-    KOKKOS_LIB_TYPE(${TARGET} INCTYPE)
-    KOKKOS_TARGET_COMPILE_OPTIONS(${${PROJECT_NAME}_LIBRARY_NAME_PREFIX}${TARGET} ${INCTYPE} ${ARGN})
-  ENDIF()
+  KOKKOS_LIB_TYPE(${TARGET} INCTYPE)
+  KOKKOS_TARGET_COMPILE_OPTIONS(${${PROJECT_NAME}_LIBRARY_NAME_PREFIX}${TARGET} ${INCTYPE} ${ARGN})
 ENDFUNCTION()
 
 MACRO(KOKKOS_ADD_TEST_DIRECTORIES)