Teach export_executable_symbols about ALIAS target

Author: Meinersbur

llvm/cmake/modules/AddLLVM.cmake

@@ -1359,6 +1359,14 @@ function(export_executable_symbols target)
     while(NOT "${new_libs}" STREQUAL "")
       foreach(lib ${new_libs})
         if(TARGET ${lib})
+          # If this is a ALIAS target, continue with its aliasee instead.
+          get_target_property(aliased_lib ${lib} ALIASED_TARGET)
+          if(aliased_lib)
+             set(new_libs ${lib_aliased_target})
+             list(APPEND newer_libs ${aliased_lib})
+             continue()
+          endif()
+
           get_target_property(lib_type ${lib} TYPE)
           if("${lib_type}" STREQUAL "STATIC_LIBRARY")
             list(APPEND static_libs ${lib})