HP Prime crashes on undef-undef*i in CAS

[parisse]

Actually, it *is* very unlikely that someone will 1/ obtain undef-undef*i and 2/ print it with the print command.
Proof: nobody reported that bug in 7 years.
Now that it is reported we will of course do our best to fix it.

I'm sorry to tell you that it is impossible to prevent all possible crashes, especially considering the increased complexity of a CAS calculator firmware. Exception handling will not save you from memory allocation errors.

The best way I know to run crashproof software is 1/ select a software that is used by a lot of users 2/ wait several years (of course this means that you will not have access to the latest functionnalities). Even if you consider your software to be reliable, save your work frequently. And if you plan to use the result of a (CAS) computation for something sensitive, check it, numerically, graphically or/and with a different kernel.