Is there a situation in which Dispose won’t be called for a ‘using’ block?

Four things that will cause Dispose to not be called in a using block:

1. A power failure on your machine when inside the using block.
2. Your machine getting melted by an atomic bomb while in the inside of the using block.
3. Uncatchable exceptions like StackOverflowException, AccessViolationException and possibly others.
4. Environment.FailFast