On Thu, Oct 25, 2012 at 1:27 PM, Chandler Carruth <[email protected]> wrote: > On Thu, Oct 25, 2012 at 9:38 AM, Jordan Rose <[email protected]> wrote: >> I think that's the best we can do. Even if the range had the beginning >> before the end (say, by trying to highlight the entirety of both macros), it >> wouldn't be "correct". We should not show ranges that don't correspond to >> something meaningful in the text. > > I actually think we can do a bit better.
Yes, we could completely change what we display, but I'm not really interested in embarking on a large architectural project at the moment. >> ...though arguably we could show a line with all macros expanded, and put >> the range there. But that's a big change in what you expect from diagnostic >> printing, and it wouldn't work in IDEs anyway. > > We get pretty close with the macro backtrace. I have sometimes > wondered if we should start the error with a synthetic preprocessed > snippet, and then give the code the user wrote in the first note, and > descend through the macro expansions in subsequent notes. > Alternatively, we could add a final note to the macro backtrace that > shows the fully preprocessed source, but that seems more likely to be > ignored. Hmm, interesting; please file a bug. :) >> >> Jordan >> >> >> On Oct 24, 2012, at 19:36 , Eli Friedman <[email protected]> wrote: >> >> Patch attached. Fixes a crash on a testcase like the following: >> >> +#define BAD_CONDITIONAL_OPERATOR (2<3)?4:5 >> +int x = BAD_CONDITIONAL_OPERATOR+BAD_CONDITIONAL_OPERATOR; >> >> We try to print a source range which starts at the 5 in the first >> expansion, and ends just after the 3 in the second expansion. > > My suggestion would be this: > > When you have a source range to highlight, and it's start or stop > location occurs within a macro, grow it to the start (or stop, resp.) > of the macro info's expansion location. This should be the start of > where the macro got expanded into the code. > > Then, if there the diagnostic location itself is inside a macro, as > you do the macro backtrace walk you'll need to address the fixme in > the diagnostic code to actually walk the source ranges back through > the macro backtrace as well, and at each level to the analogous > transform to grow the range at that level. We already do this; we just don't do it correctly for the case where the start and/or end locations come from a different expansion than the caret. -Eli _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
