Intel compiler used to automatically include -lstdc++ but no longer. …

…Have to add it explicitly.

CMakeLists.txt

@@ -342,12 +342,7 @@ if (APEX_USE_PEDANTIC)
     endif(APEX_WITH_CUDA)
 endif (APEX_USE_PEDANTIC)
 
-if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "IntelLLVM")
-    set(APEX_STDCXX_LIB "" CACHE STRING "C++ library for linking")
-    message("IntelLLVM compiler detected, no stdc++ library needed")
-else()
-    set(APEX_STDCXX_LIB stdc++ CACHE STRING "C++ library for linking")
-endif()
+set(APEX_STDCXX_LIB stdc++ CACHE STRING "C++ library for linking")
 
 # PGI and Intel don't like the concurrentqueue code.
 if (NOT "${CMAKE_CXX_COMPILER_ID}" STREQUAL "PGI")
@@ -365,35 +360,6 @@ set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-# add_definitions(-std=c++11)
-#include(CheckCXXCompilerFlag)
-#CHECK_CXX_COMPILER_FLAG("-std=c++17" COMPILER_SUPPORTS_CXX17)
-#if(COMPILER_SUPPORTS_CXX17)
-#    set(CMAKE_CXX_SUPPORT_FLAG "-std=c++17" CACHE STRING "CXX Support Flag" FORCE)
-#else()
-#    CHECK_CXX_COMPILER_FLAG("-std=c++14" COMPILER_SUPPORTS_CXX14)
-#    if(COMPILER_SUPPORTS_CXX14)
-#        set(CMAKE_CXX_SUPPORT_FLAG "-std=c++14" CACHE STRING "CXX Support Flag" FORCE)
-#    else()
-#        CHECK_CXX_COMPILER_FLAG("-std=c++1y" COMPILER_SUPPORTS_CXX1Y)
-#        if(COMPILER_SUPPORTS_CXX1Y)
-#            set(CMAKE_CXX_SUPPORT_FLAG "-std=c++1y" CACHE STRING "CXX Support Flag" FORCE)
-#        else()
-#            CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
-#            if(COMPILER_SUPPORTS_CXX11)
-#                set(CMAKE_CXX_SUPPORT_FLAG "-std=c++11" CACHE STRING "CXX Support Flag" FORCE)
-#            else()
-#                CHECK_CXX_COMPILER_FLAG("-std=c++0x" COMPILER_SUPPORTS_CXX0X)
-#                if(COMPILER_SUPPORTS_CXX0X)
-#                    set(CMAKE_CXX_SUPPORT_FLAG "-std=c++0x" CACHE STRING "CXX Support Flag" FORCE)
-#                else()
-#                    message(FATAL_ERROR " Compiler ${CMAKE_CXX_COMPILER} has no C++11 support.")
-#                endif()
-#            endif()
-#        endif()
-#    endif()
-#endif()
-
 # By the way, GCC lies.  It accepts the flag, but doesn't have the support.
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
     if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.1)