That's applying it to the type definition. At the type use: https://godbolt.org/g/RMYVW7
On Mon, Jan 9, 2017 at 9:56 AM, Zachary Amsden <[email protected]> wrote: > GCC doesn't catch this when optimization is enabled and the result is > discarded: > > https://godbolt.org/g/4b0BQC > > I think that means a type wrapper approach is needed, which probably > necessitates option 1. > > - Zach > > On Mon, Jan 9, 2017 at 9:17 AM, Jim Apple <[email protected]> wrote: > >> My vote, as I mentioned on the patch, is option 1. I see MUST_USE(T) >> as a property of T, like const T or volatile T. I think it is dual to >> move semantics or to Rust's ability to temporarily or permanently >> consume values so that /only/ one copy is in use rather than >> MUST_USE's /at least one/. >> >> https://en.wikipedia.org/wiki/Substructural_type_system >> >> On Fri, Jan 6, 2017 at 4:05 PM, Taras Bobrovytsky >> <[email protected]> wrote: >> > I'd vote for #2. I think it's better to have less important information >> > (such as qualifiers) towards the end of lines. (I think it would be nice >> if >> > modifiers such as public and private were at the end of method >> declarations >> > in Java, for example: void myMethod() private static {...}) >> > >> > On Fri, Jan 6, 2017 at 3:38 PM, Daniel Hecht <[email protected]> >> wrote: >> > >> >> As I indicated in the original review, my preference is #2 but I don't >> feel >> >> too strongly. >> >> >> >> On Fri, Jan 6, 2017 at 2:59 PM, Tim Armstrong <[email protected]> >> >> wrote: >> >> >> >> > Hi All, >> >> > I wanted to poll the Impala community for opinions about style for >> >> > declaring functions where the caller is expected to do something with >> the >> >> > return value. >> >> > >> >> > Ideally we'd be able to declare Status with an attribute that made >> this >> >> > take effect globally, but unfortunately that's not available until >> C++17. >> >> > >> >> > So we need to annotate each Status-returning function. The two >> >> alternatives >> >> > we discussed on this CR (https://gerrit.cloudera.org/#/c/4878/) were: >> >> > >> >> > #1 - a special macro wrapping Status >> >> > >> >> > MUST_USE(Status) DoSomethingThatCanFail(int64_t foo, Bar* bar); >> >> > >> >> > Pros: >> >> > * Closely connected to the return type that it affects >> >> > * It's easier to search/replace Status with MUST_USE(Status) >> >> > >> >> > Cons: >> >> > * Could get visually noisy if we use it everywhere >> >> > >> >> > #2 - a macro that gets appended to the declaration: >> >> > >> >> > Status DoSomethingThatCanFail(int64_t foo, Bar* bar) >> WARN_UNUSED_RESULT; >> >> > >> >> > Pros: >> >> > * Macro is slightly >> >> > * Less visually noisy since it's at the end of the declaration >> >> > >> >> > What do people think? >> >> > >> >> >>
