Created attachment 289 [details]
Model provocating the error
When a function is declared as
void func(double& x) ...
the arguments do not seem to be handled correctly by the engine. As far as I can tell, the uppaaal-byte-code around handling double-references is broken.
On the first check the variable is not reset the target invariant is violated.
However the second time the variable is reset and the same check succeeds.
Probably has something to do with compilation process.