[RFC] GCC caret diagnostics

[Tom Tromey]

>>>>> "Ian" == Ian Lance Taylor <iant@google.com> writes:

>> Why? Isn't the operator available at that point?

Ian> The location information, if present, is technically available, but it
Ian> would require some surgery to actually get it.

I think the high-level decision to be made here is whether we want to
support "full" diagnostics through the whole compiler pipeline.

If yes, then one consequence is that someone will have to modify code
like this to use proper location information.

We might even have to do that if the answer is "no", if the messages
are coming from something that is called by the front end.

Ian> As we move to tuples, we will have even less location information at
Ian> this point.  We will almost certainly not have the location of any
Ian> operators.  This is in general a good thing, as we won't be paying the
Ian> memory space to carry them through the whole middle-end.

I'm not certain that this is the tradeoff I prefer, but I haven't
exactly done a survey of what diagnostics are emitted where.  My
general worry is that these more distant (from the FE) diagnostics
will also be the ones where having good location information would be
the most useful.

Tom