[llvm] [libsycl] Fix debug build error caused by RTTI option mismatch (PR #210997)

[Kseniya Tikhomirova via llvm-commits]

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@@ -1,14 +1,15 @@
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/../../runtimes/cmake/Modules")
 include(WarningFlags)
 function(add_sycl_rt_library LIB_TARGET_NAME LIB_OBJ_NAME LIB_OUTPUT_NAME)
-  cmake_parse_arguments(ARG "" "" "COMPILE_OPTIONS;SOURCES" ${ARGN})
+  cmake_parse_arguments(ARG "" "" "COMPILE_OPTIONS;SOURCES;NO_RTTI_SOURCES" ${ARGN})
 
   add_library(${LIB_OBJ_NAME} OBJECT ${ARG_SOURCES})
 
   # Common compilation step setup
   target_compile_definitions(${LIB_OBJ_NAME} PRIVATE
               $<$<STREQUAL:${CMAKE_SYSTEM_NAME},Windows>:_LIBSYCL_BUILDING_LIBRARY>)
   cxx_add_warning_flags(${LIB_OBJ_NAME} ${LIBSYCL_ENABLE_WERROR} ${LIBSYCL_ENABLE_PEDANTIC})
+  set_source_files_properties(${ARG_NO_RTTI_SOURCES} PROPERTIES COMPILE_FLAGS -fno-rtti)
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KseniyaTikhomirova wrote:

LLVM has its own flag to enable RTTI for all projects. Should we add condition here then?

https://github.com/llvm/llvm-project/pull/210997