On Thu, Oct 25, 2012 at 2:57 PM, Eli Friedman <[email protected]> wrote: > 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.
Yes, but do we do the first paragraph correctly? I think we can do the first paragraph and fix the crash/misbehavior you're talking about. _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
