underdetermined initialization problems lead to division by zero

[Lennart Ochel]

In some cases underdetermined initialization problems lead to division by zero errors. This happens if a bad set of variables is selected for which additional initial conditions get introduced.

model test
  Real a(start = 1);
  Real b(start = 1);
  parameter Real p = 0;
initial equation
  b = p * a;
equation
  der(b) = 0;
  der(a) = 0;
end test;

Warning: Assuming fixed start value for the following 1 variables:
         b:VARIABLE(start = 1.0 ) .test, .Real type: Real

assert | debug | division by zero at time 0, (a=1) / (b=0), where divisor b expression is: p

In this example, an additional initial condition should get introduced for a instead of b.

[Martin Sjölund]

This ticket was not closed for 1.9.1, which has now been released. It was batch modified for milestone 1.9.2 (but maybe an empty milestone was more appropriate; feel free to change it).

[Martin Sjölund]

Milestone changed to 1.9.3 since 1.9.2 was released.

[Martin Sjölund]

Moved to new milestone 1.9.4

[Martin Sjölund]

Milestone pushed to 1.9.5

[Martin Sjölund]

Milestone renamed

[Martin Sjölund]

Ticket retargeted after milestone closed

[Martin Sjölund]

Milestone moved to 1.12.0 due to 1.11.0 already being released.

[Francesco Casella]

The milestone of this ticket has been reassigned to "Future".

If you think the issue is still valid and relevant for you, please select milestone 1.13.0 for back-end, code generation and run-time issues, or 2.0.0 for front-end issues.

If you are aware that the problem is no longer present, please select the milestone corresponding to the version of OMC you used to check that, and set the status to "worksforme".

In both cases, a short informative comment would be welcome.