I was studying Computation Theory, NonDeterministic Stack Automata, and I had some trouble with code simplification.
When my code is not simplified, it compiles.
When I try to simplify, removing old_ variables, it does not compile. It stays forever at 2% compilation.
Maybe I'm totally wrong... Maybe some compilation directive... Maybe some new feature...
Please, forward it to he who makes quartus next release.
Vinicius Claudino Ferraz, from Brazil