c++ - Qt example: no mutex lock when reading, why? -

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i looking @ this example, , raises queston me: when looking @ this file mutex being used when accessing global variable m_abort when being changed. when run method reads it, nothing mutex @ all. why?

well, cannot see purpose of mutex @ all. both reading , writing m_abort can performed without mutex protection it's bool variable, , value changed atomically (at least on platforms). , if write not atomic , variable can have inconsistent value - can either false or true, , read true (since value written there true).


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