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J. Day" , "Kernel Janitors List" X-Mailer: aerc 0.21.0-0-g5549850facc2 References: <888a08d7-1d0b-f114-dd3d-e840f16c8803@crashcourse.ca> In-Reply-To: I took a closer look at this. Many of the occurences here are actually used to check if a binary flag has more then one bit set. This is quite a common pattern. Eg. 'if (a & (a - 1))' would pass if a =3D 0b100, not if a =3D 0b110. Since= : 0b100 - 0b001 =3D 0b011 -> (0b100 & 0b011) =3D> false 0b110 - 0b001 =3D 0b101 -> (0b100 & 0b101) =3D> true The power of two check would 'normally' use the negation: 'if (!(a & (a - 1)))' Just a heads up so anyone else reading this doesn't go blindly swapping out this pattern for 'is_power_of_2()'. You need to apply some thinking. No 'sed' work. Br, Linus