diff --git a/package/micropython/micropython.mk b/package/micropython/micropython.mk
index e1e1f88d51..826247069e 100644
--- a/package/micropython/micropython.mk
+++ b/package/micropython/micropython.mk
@@ -21,12 +21,12 @@ MICROPYTHON_IGNORE_CVES += CVE-2024-8947
 # Use fallback implementation for exception handling on architectures that don't
 # have explicit support.
 ifeq ($(BR2_i386)$(BR2_x86_64)$(BR2_arm)$(BR2_armeb),)
-MICROPYTHON_CFLAGS = -DMICROPY_GCREGS_SETJMP=1
+MICROPYTHON_CFLAGS += -DMICROPY_GCREGS_SETJMP=1
 endif
 
 # xtensa has problems with nlr_push, use setjmp based implementation instead
 ifeq ($(BR2_xtensa),y)
-MICROPYTHON_CFLAGS = -DMICROPY_NLR_SETJMP=1
+MICROPYTHON_CFLAGS += -DMICROPY_NLR_SETJMP=1
 endif
 
 # https://github.com/micropython/micropython/issues/14115