sidney added a comment. In http://reviews.llvm.org/D17043#348525, @alexfh wrote:
> I'd like to note that there is a library-side way to mitigate this issue > using the `[[clang::warn_unused_result]]` attribute on `vector::empty()` and > similar methods: Using an attribute sounds much better than this kind of check and I'd be fine with throwing this patch out completely. IMHO the diagnostic is bad, though. A message like this: > q.cc:17:3: warning: ignoring return value of function declared with > warn_unused_result attribute [-Wunused-result] > v.empty(); > ^~~~~~~ > …is way too literal. It could indicate two completely different issues: 1. `empty()` just tells you whether the container is empty. 2. `empty()` has side effects and returns a value which should never be ignored (like recv, send, and scanf). Searching for this warning (https://www.google.com/search?q="Wunused-result";) turns up tons of confusion. I'm not an expert on attributes. Is there a way to attach metadata (like a subtype, or a string description), so that calls without side effects could have a diagnostic more like the one I wrote, and things like `recv(2)` and `scanf(3)` could have rich messages? I'm going to hold of on addressing any of your other comments until I hear back. Thanks for the review! http://reviews.llvm.org/D17043 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
