The setjmp() macro should be invoked from only one of the contexts listed in §7Section 7.13.1.1 of of the C Standard [ISO/IEC 9899:2011]. Invoking setjmp() outside of one of these contexts results in undefined behavior. (See undefined behavior 125.)
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 behaviors 127 and 10.)
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