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Last Updated: 11/22/2016

warning C28129: An assignment has been made to an operand, which should only be modified using bit sets and clears

The driver is using an assignment to modify an operand. Assigning a value might unintentionally change the values of bits other than those that it needs to change, resulting in unexpected consequences.


The following code example elicits this warning.

fdo->Flags = DO_BUFFERED_IO;

The following code example avoids this warning.

fdo->Flags |= DO_BUFFERED_IO;

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