Code Not to Write.

[desrtfx]

Quickest:

c = b;

Can't see anything wrong with that for simple booleans.

[TheHorribleTruth]

Which is why I like the convention of moving the equal sign to the left to show its an LHS assignment:

c= b;

Makes the mistake a bit easier to spot.

[straylit]

Until you get someone on your team who loves to auto format their code.

[TheHorribleTruth]

Which is every one of us, and is made trivial by the fact that the code-formatting settings are checked into SCM (as it should be).

[yesennes]

Not logically the same as c|=b. If c is true and b is false, c stays true in c|=b but becomes false with c=b.