diff --git a/CMakeLists.txt b/CMakeLists.txt
index 168f7c1efc916adb85c7dc82f9e20bdbd35392e6..e0eb37406d4dc89a9605358903a793026cbf6ba1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -624,12 +624,6 @@ if (MORSE_DISTRIB_DIR OR EXISTS "${CMAKE_SOURCE_DIR}/cmake_modules/")
                     message("-- ${Red}Looking for starpu with starpu_mpi_data_register"
                     " - starpu_mpi_data_register() test fails in StarPU${ColourReset}")
                     message("-- ${Red}Check in CMakeFiles/CMakeError.log to figure out why it fails${ColourReset}")
-                    if (CHAMELEON_SIMULATION)
-                        # function detection fails due to conflicting main
-                        # definitions. We know that the StarPU-simgrid-MPI version
-                        # has it anyway.
-                        add_definitions(-DHAVE_STARPU_MPI_DATA_REGISTER)
-                    endif()
                 endif()
             endif()
             if(HWLOC_FOUND AND HWLOC_LIBRARY_DIRS)