diff --git a/CMakeLists.txt b/CMakeLists.txt
index 586d7c8eb08..dfd1b4f75da 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2133,12 +2133,15 @@ endif()
 set(llext_edk_file ${PROJECT_BINARY_DIR}/${CONFIG_LLEXT_EDK_NAME}.tar.xz)
 
 # TODO maybe generate flags for C CXX ASM
+zephyr_get_compile_definitions_for_lang(C zephyr_defs)
 zephyr_get_compile_options_for_lang(C zephyr_flags)
 
 # Filter out non LLEXT and LLEXT_EDK flags - and add required ones
-llext_filter_zephyr_flags(LLEXT_REMOVE_FLAGS ${zephyr_flags} llext_edk_cflags)
-llext_filter_zephyr_flags(LLEXT_EDK_REMOVE_FLAGS ${llext_edk_cflags} llext_edk_cflags)
+llext_filter_zephyr_flags(LLEXT_REMOVE_FLAGS ${zephyr_flags} llext_filt_flags)
+llext_filter_zephyr_flags(LLEXT_EDK_REMOVE_FLAGS ${llext_filt_flags} llext_filt_flags)
 
+set(llext_edk_cflags ${zephyr_defs} -DLL_EXTENSION_BUILD)
+list(APPEND llext_edk_cflags ${llext_filt_flags})
 list(APPEND llext_edk_cflags ${LLEXT_APPEND_FLAGS})
 list(APPEND llext_edk_cflags ${LLEXT_EDK_APPEND_FLAGS})
 
diff --git a/cmake/llext-edk.cmake b/cmake/llext-edk.cmake
index 24ea41fa143..e78498c7845 100644
--- a/cmake/llext-edk.cmake
+++ b/cmake/llext-edk.cmake
@@ -118,8 +118,8 @@ foreach(flag ${llext_edk_cflags})
 endforeach()
 set(llext_edk_cflags ${new_cflags})
 
-list(APPEND base_flags_make ${llext_edk_cflags} ${imacros_make} -DLL_EXTENSION_BUILD)
-list(APPEND base_flags_cmake ${llext_edk_cflags} ${imacros_cmake} -DLL_EXTENSION_BUILD)
+list(APPEND base_flags_make ${llext_edk_cflags} ${imacros_make})
+list(APPEND base_flags_cmake ${llext_edk_cflags} ${imacros_cmake})
 
 separate_arguments(include_dirs NATIVE_COMMAND ${INTERFACE_INCLUDE_DIRECTORIES})
 file(MAKE_DIRECTORY ${llext_edk_inc})