On Mon, Oct 16, 2017 at 8:09 PM, David Blaikie <dblai...@gmail.com> wrote: > Would it be better/possible to improve the warning to not have this false > positive, rather than suppressing it? I am willing to look into it, once there is a clear minimal test-case, that does not boil down to completely ignoring std::numeric_limits<>.
Right now, sadly, i do not see any simple false-positive here. Roman. > On Sun, Oct 15, 2017 at 1:12 PM Roman Lebedev via cfe-commits > <cfe-commits@lists.llvm.org> wrote: >> >> Author: lebedevri >> Date: Sun Oct 15 13:12:42 2017 >> New Revision: 315874 >> >> URL: http://llvm.org/viewvc/llvm-project?rev=315874&view=rev >> Log: >> Silence clang's -Wtautological-constant-compare in >> last_write_time.pass.cpp >> >> Previously this broke the builders, when D38101 was committed. >> Silence the warning so that it can be re-landed. >> >> Modified: >> >> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp >> >> Modified: >> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp >> URL: >> http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp?rev=315874&r1=315873&r2=315874&view=diff >> >> ============================================================================== >> --- >> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp >> (original) >> +++ >> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp >> Sun Oct 15 13:12:42 2017 >> @@ -88,6 +88,13 @@ bool TestSupportsNegativeTimes() { >> return !ec && new_write_time <= -5; >> } >> >> +// In some configurations, the comparison is tautological and the test is >> valid. >> +// We disable the warning so that we can actually test it regardless. >> +#if defined(__clang__) >> +#pragma clang diagnostic push >> +#pragma clang diagnostic ignored "-Wtautological-constant-compare" >> +#endif >> + >> bool TestSupportsMaxTime() { >> using namespace std::chrono; >> using Lim = std::numeric_limits<std::time_t>; >> @@ -106,11 +113,22 @@ bool TestSupportsMaxTime() { >> return !ec && new_write_time > max_sec - 1; >> } >> >> +#if defined(__clang__) >> +#pragma clang diagnostic pop >> +#endif >> + >> static const bool SupportsNegativeTimes = TestSupportsNegativeTimes(); >> static const bool SupportsMaxTime = TestSupportsMaxTime(); >> >> } // end namespace >> >> +// In some configurations, the comparison is tautological and the test is >> valid. >> +// We disable the warning so that we can actually test it regardless. >> +#if defined(__clang__) >> +#pragma clang diagnostic push >> +#pragma clang diagnostic ignored "-Wtautological-constant-compare" >> +#endif >> + >> // Check if a time point is representable on a given filesystem. Check >> that: >> // (A) 'tp' is representable as a time_t >> // (B) 'tp' is non-negative or the filesystem supports negative times. >> @@ -127,6 +145,10 @@ inline bool TimeIsRepresentableByFilesys >> return true; >> } >> >> +#if defined(__clang__) >> +#pragma clang diagnostic pop >> +#endif >> + >> TEST_SUITE(exists_test_suite) >> >> TEST_CASE(signature_test) >> >> >> _______________________________________________ >> cfe-commits mailing list >> cfe-commits@lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
