graphics/NxWidgets/nxwm/src/ccalibration.cxx:  Correct and error in the type of the return value.
@@ -590,7 +590,7 @@ FAR void *CCalibration::calibration(FAR void *arg)
if (!This->createWidgets())
{
gerr("ERROR: failed to create widgets\n");
- return false;
+ return (FAR void *)0;
}
// No samples have yet been collected
