george.burgess.iv added a comment. Thanks for the feedback!
> You noted, that the C++ warning would catch this case, but does not get > triggered in C. Would it be wort to generalize the concern and have a warning > that catch the comparison, regardless of the macro? I'm not quite sure how we would go about that with confidence. The code we'd need to catch looks something like: typeof(foo() == y) x; /* snip */ bar(x == -1); // warning: comparison is pointless If we could tell that `x`'s type was inferred from a comparison op, we could warn here. However, if the user used `x` as anything but a C++ `bool` in `/* snip */`, the warning would be incorrect. We could maybe do some sort of range analysis by walking the AST, but that sounds like more like a static analyzer thing. ...And none of that would catch glibc's `TEMP_FAILURE_RETRY` macro, unless we wanted to apply said analysis to all integral variables. > Do other major libraries define a similar macro but name it differently? If > so, including there names would be worthwhile. Dunno. A quick search for alternatives on MacOS said "no; #define it yourself," and I know so little about Windows that I have no clue if a `TEMP_FAILURE_RETRY`-like macro would even be reasonable there. :) If you have anything in mind, I'm happy to add it. https://reviews.llvm.org/D45059 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
