[OT] Identifying unused include directives?

[Robert Dewar]

> Anyone know a good way to automatically identify unneeded #include statements?Seems like this is something gcc could do...

The general case seems impossible to solve (indeed it is trivially equivalent
to the halting problem whether a given #include affects the semantics of
a given program). So the first job is to define exactly what the scope
of the task is, and this seems pretty difficult.