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+---- Thread: Rule 12.4 - Do not use expressions with side effects (/showthread.php?tid=990)
Rule 12.4 - Do not use expressions with side effects - jbrookley - 24-10-2013
Hello everyone,
I am having a problem with rule 12.4 (Do not use expressions with side effects in the right hand operand of a logical '&&' operator). My code is as follows:
[code]if ((DualDAC == 0) && (ADC1Flag
Re: Rule 12.4 - Do not use expressions with side effects - Steve Montgomery - 25-10-2013
I'm assuming that ADC1Flag has a volatile qualified type so that the act of reading its value it is a side-effect. That being the case, I think you have only two options: either nest the tests (as you did in your proposed solution), or perform the volatile access first, e.g.
[code]flag = ADC1Flag
Re: Rule 12.4 - Do not use expressions with side effects - jbrookley - 28-10-2013
So glad I posted here, I didn't understand WHY this was happening. While it's kind of a bummer to need a nested if loop, codewise, apparently, it's the same size so it's not a huge deal. Thanks for your help!
Re: Rule 12.4 - Do not use expressions with side effects - misra-c - 13-12-2013
We feel that Steve has given a good response to this question and have nothing more to add.