Pass CXX standard information to external projects

external/InstallKFParticle.cmake

@@ -8,6 +8,7 @@ download_project_if_needed(PROJECT         kfparticle_source
                            GIT_TAG         "98712bbb2e2ae633e16a543ec38fea62a9ca2053"
                            SOURCE_DIR      ${CMAKE_CURRENT_SOURCE_DIR}/KFParticle
                            TEST_FILE       CMakeLists.txt
+                           PATCH_COMMAND   "patch -p1 < ${CMAKE_CURRENT_SOURCE_DIR}/KFParticle.patch"
                           )
 
 If(ProjectUpdated)
@@ -27,6 +28,7 @@ ExternalProject_Add(KFPARTICLE
              -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
              -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
              -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
+             -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
              -DCMAKE_INSTALL_PREFIX=${CMAKE_BINARY_DIR}
              -DVc_INCLUDE_DIR=${Vc_INCLUDE_DIR}
              -DVc_LIBRARIES=${Vc_LIBRARY}

external/InstallNicaFemto.cmake

@@ -32,6 +32,7 @@ ExternalProject_Add(NICAFEMTO
              -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
              -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
              -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
+             -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
              -DCMAKE_INSTALL_PREFIX=${CMAKE_BINARY_DIR}
              -DROOTSYS=${SIMPATH}
 	     -DJSROOT=${CMAKE_CURRENT_SOURCE_DIR}

external/KFParticle.patch

+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 6fbd90c..5a131e9 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -12,11 +12,13 @@ macro(add_target_property _target _prop _value)
+ endmacro(add_target_property)
+ 
+ if (CMAKE_VERSION VERSION_LESS "3.1")
+-if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+-  set (CMAKE_CXX_FLAGS "--std=gnu++11 ${CMAKE_CXX_FLAGS}")
+-endif ()
++  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
++    set (CMAKE_CXX_FLAGS "--std=gnu++11 ${CMAKE_CXX_FLAGS}")
++  endif ()
+ else ()
+-  set (CMAKE_CXX_STANDARD 11)
++  if(NOT CMAKE_CXX_STANDARD)
++    set (CMAKE_CXX_STANDARD 11)
++  endif()
+ endif ()
+ 
+ list(APPEND CMAKE_PREFIX_PATH $ENV{ROOTSYS} ${ROOTSYS})