In LabVIEW 2010, when changing a controller or indicator with unit label from 'modern' to 'system' (or vice versa), the unit label disappears. It becomes empty.
Somehow it is still active (no coercion dot appears), but hidden from view. A bit annoying.
Actually, the unit label is emptied - it's not hidden. It's actually still there on the front panel, but it's set to an empty string. If you use the property Unit Label.Text you will see that before you replace the control the property has the value corresponding to the unit label. If you replace the control (even with the same exact kind), the property is then empty, meaning the unit label is gone. When you replace the control with another of its kind the View -> Unit Label is still checked, even though there're no unit actually specified. The marquee around the unit label is still active, though.
I don't quite follow what you're referring to about the coercion dot.
Oh, now I understand what you mean. Yeah, that's even weirder.
More info: If you take the control that you just replaced, and uncheck the Visible Item -> Unit Label item the VI remains unbroken. If you then check Visible Item -> Unit Label it gets broken, apparently because the compiler woke up. Oddly, forcing a recompile after replacing the control doesn't cause the VI to be broken as it should.
thank you for bringing this to our attention. We have reproduced the error and filed a Corrective Action Request to correct it in a subsequent LabVIEW release. The CAR number is 255865.
In the meantime I'm afraid you'll just have to be careful when replacing controls with labels to ensure that no error creeps into the VI.
