Remove redundant expression #776
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This is either a bug-causing expression, or a redundant statement of logic. Consider the following logic, but applied on the bit-level: Here is a tautology for every bit: A ^ -B -> A. This means, A & -B requires A must be 1 for it to stay. !(pp & ~_PTHREAD_PRIORITY_FLAGS_MASK) being true means every bit that is a 1 in pp is a bit that will yield 0 when XORed with _PTHREAD_PRIORITY_FLAGS_MASK. Because of this, &= _PTHREAD_PRIORITY_FLAGS_MASK has no effect. Therefore, !(pp & ~_PTHREAD_PRIORITY_FLAGS_MASK) is redundant. However, because the comment mentions an and, there is the possibility the entire conditional may have been incorrectly written, causing bugs.
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This is either a bug-causing expression, or a redundant statement of logic.
Consider the following logic, but applied on the bit-level: Here is a tautology for every bit: A ^ -B -> A.
This means, A & -B requires A must be 1 for it to stay.
!(pp & ~_PTHREAD_PRIORITY_FLAGS_MASK) being true means every bit that is a 1 in pp is a bit that will yield 0 when XORed with _PTHREAD_PRIORITY_FLAGS_MASK.
Because of this, &= _PTHREAD_PRIORITY_FLAGS_MASK has no effect. Therefore, !(pp & ~_PTHREAD_PRIORITY_FLAGS_MASK) is redundant. However, because the comment mentions an and, there is the possibility the entire conditional may have been incorrectly written, causing bugs.