Index: cmake/modules/AddLLVM.cmake
===================================================================
--- cmake/modules/AddLLVM.cmake
+++ cmake/modules/AddLLVM.cmake
@@ -28,6 +28,8 @@
     elseif(MSVC)
       list(APPEND LLVM_COMPILE_DEFINITIONS _HAS_EXCEPTIONS=0)
       list(APPEND LLVM_COMPILE_FLAGS "/EHs-c-")
+    elseif (CMAKE_CXX_COMPILER_ID MATCHES "XL")
+      list(APPEND LLVM_COMPILE_FLAGS "-qnoeh")
     endif()
   endif()
 
@@ -41,6 +43,8 @@
       list(APPEND LLVM_COMPILE_FLAGS "-fno-rtti")
     elseif (MSVC)
       list(APPEND LLVM_COMPILE_FLAGS "/GR-")
+    elseif (CMAKE_CXX_COMPILER_ID MATCHES "XL")
+      list(APPEND LLVM_COMPILE_FLAGS "-qnortti")
     endif ()
   elseif(MSVC)
     list(APPEND LLVM_COMPILE_FLAGS "/GR")