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If you once choosen a architecture, system and cpu and saved
the configuration, some defaults are set. Any reconfiguration
of these settings might create a non-valid configuration.
You can even get some strange side effects, where you can't
select some stuff.

Config.in

@@ -24,6 +24,10 @@ source "target/config/Config.in.systemopts"
 source "target/config/Config.in.subsystem"
 source "target/config/Config.in.qemuopts"
 source "target/config/Config.in.cpu"
+
+comment "After you saved your configuration once, you shouldn't change anything above"
+	depends on ADK_TARGET_OS_LINUX && !ADK_APPLIANCE_TOOLCHAIN && !ADK_TARGET_CHOOSE_ARCH
+
 source "target/config/Config.in.tasks"
 
 menu "Firmware configuration"