Restrictions on Termination Handlers

 

The latest version of this topic can be found at Restrictions on Termination Handlers.

You cannot use a goto statement to jump into a __try statement block or a __finally statement block. Instead, you must enter the statement block through normal flow of control. (You can, however, jump out of a __try statement block.) Also, you cannot nest an exception handler or termination handler inside a __finally block.

In addition, some kinds of code permitted in a termination handler produce questionable results, so you should use them with caution, if at all. One is a goto statement that jumps out of a __finally statement block. If the block is executing as part of normal termination, nothing unusual happens. But if the system is unwinding the stack, that unwinding stops, and the current function gains control as if there were no abnormal termination.

A return statement inside a __finally statement block presents roughly the same situation. Control returns to the immediate caller of the function containing the termination handler. If the system was unwinding the stack, this process is halted, and the program proceeds as if there had been no exception raised.

See Also

Writing a Termination Handler
Structured Exception Handling (C/C++)