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- the entire controlling expression of a selection or iteration statement
- one operand of a relational or equality operator with the other operand an integer constant expression, with the resulting expression being the entire controlling expression of a selection or iteration statement
- the operand of a unary
!operator with the resulting expression being the entire controlling expression of a selection or iteration statement - the entire expression of an expression statement (possibly cast to void)
Invoking setjmp outside of one of these contexts results in undefined behavior (see Undefined Behavior #119).
After invoking longjmp, non-volatile-qualified local objects should not be accessed if their values could have changed since the invocation of setjmp. Their value in this case is considered indeterminate and accessing them is undefined behavior (see Undefined Behavior #121).
longjmp should never be used to return control to a function that has terminated execution (see Undefined Behavior #120).
This recommendation is related to SIG32-C. Do not call longjmp() from inside a signal handler and ENV32-C. All atexit handlers must return normally.
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