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copied!<p>As evidenced by the line number 1035 in the error message, your code snippet has considerably simplified the actual problem code. You went too far. There is no clue as to how you are using 'first'. The problem is that the compiler can't figure that out even in the real code. It is afraid that the value of 'first' after a non-zero return from 'setjmp' may not be what you think it is. This is because you changed its value both before and after the first call (zero return) to 'setjmp'. If the variable was stored in a register, the value will probably be different than if it were stored in memory. So the compiler is being conservative by giving you the warning. </p> <p>To take a blind leap and answer the question, you may be able to get rid of the warning message by qualifying the declaration of 'first' with 'volatile'. You could also try making 'first' global. Perhaps by dropping the optimization level (-O flag), you could cause the compiler to keep variables in memory. These are quick fixes, and may actually hide a bug.</p> <p>You should really take a look at your code, and how you are using 'first'. I'll take another wild guess, and say you may be able to eliminate that variable. Could that name, 'first', mean you are using it to indicate a first call (zero return) to 'setjmp'? If so, get rid of it - redesign your logic.</p> <p>If the real code just exits on a non-zero return from 'setjmp' (as in the snippet), then the value of 'first' doesn't matter in that logic path. Don't use it on both sides of the 'setjmp'.</p>

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