Turn abnormal CompilerError into regular Panic

[JaroslavTulach]

Pull Request Description

Fixes #7582 by turning ComplerError (during construction of Truffle nodes in IrToTruffle) into PanicException. That way the abnormal situation turns into a regular panic. Such a panic can be caught or let to be propagated - just like any other panic during execution.

Important Notes

This is a safety net fix. Investigation of targeted, better fix may continue.

Checklist

Please ensure that the following checklist has been satisfied before submitting the PR:

• All code follows the
  Scala,
  Java,
• All code has been tested:
  • Unit tests have been written where possible.

[4e6]

Shouldn't we turn a._ into a lambda x-> a.x instead of an error?

[JaroslavTulach]

Shouldn't we turn a._ into a lambda x-> a.x instead of an error?

Interesting idea, but is it correct?

x -> a.x doesn't mean that x is used on a. It means to invoke symbol "x" on a - e.g. the x variable would be unused.

My (a language semantic amateur) conclusion: No, we shall not turn a._ into x->a.x.