Currently, if you try to generate the executable model using the kie-maven-plugin with

YES or YES_WITHDRL

but you forget to add the drools-model-compiler the plugin will generate the sources but the compile phase will fail.

It should be better to avoid generating the source, revert to the NO behaviour and show a warning of what happened.

This will help the migration as customer who will upgrade to 7.7 will have the exec model as a default but they won't have the jar in the pom.xml