How dangerous is it to compare floating point values?

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I know UIKit uses CGFloat because of the resolution independent coordinate system.

But every time I want to check if for example frame.origin.x is 0 it makes me feel sick:

if (theView.frame.origin.x == 0) {
    // do important operation
}

Isn’t CGFloat vulnerable to false positives when comparing with ==, <=, >=, <, >?
It is a floating point and they have unprecision problems: 0.0000000000041 for example.

Is Objective-C handling this internally when comparing or can it happen that a origin.x which reads as zero does not compare to 0 as true?

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