diff --git a/cpu/mpc5xxx/start.S b/cpu/mpc5xxx/start.S
index a2ac999..3936b55 100644
--- a/cpu/mpc5xxx/start.S
+++ b/cpu/mpc5xxx/start.S
@@ -107,12 +107,12 @@
 	/*--------------------------------------------------------------*/
 
 #if defined(CFG_LOWBOOT)
-#if defined(CFG_RAMBOOT)
-#error CFG_LOWBOOT is incompatible with CFG_RAMBOOT
-#endif /* CFG_RAMBOOT */
-#if defined(CFG_LOWBOOT)
-#error CFG_LOWBOOT is incompatible with MGT5100
-#endif /* CFG_LOWBOOT */
+# if defined(CFG_RAMBOOT)
+#  error CFG_LOWBOOT is incompatible with CFG_RAMBOOT
+# endif /* CFG_RAMBOOT */
+# if defined(CONFIG_MGT5100)
+#  error CFG_LOWBOOT is incompatible with MGT5100
+# endif /* CONFIG_MGT5100 */
 	lis	r4, CFG_DEFAULT_MBAR@h
 	lis	r3,	START_REG(CFG_BOOTCS_START)@h
 	ori	r3, r3, START_REG(CFG_BOOTCS_START)@l