I was able to reproduce the problem and I believe it is the same problem as reported here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122864. The warning is produced.
It was already fixed on master by: commit r16-5627-g4e7213aa081f1c0ca5b7e6a60d4e7ba5bcfb1f8a <https://gcc.gnu.org/cgit/gcc/commit/?id=4e7213aa081f1c0ca5b7e6a60d4e7ba5bcfb1f8a> Author: Tomasz KamiÅski <[email protected]> Date: Wed Nov 26 14:28:39 2025 +0100 libstdc++: Fix typo in operator used in __pack_ints [PR122864 <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122864>] `<=` was used instead of `<<`, this was detected by clang warning. PR libstdc++/122864 <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122864> libstdc++-v3/ChangeLog: * include/std/chrono (chrono::__pack_ints): Replace `<=` with `<<`. On Wed, Nov 26, 2025 at 3:28 PM Tomasz Kaminski <[email protected]> wrote: > Would it be possible to include information on what the failure was? > I have already pushed a patch that corrects warnings here, and use of > `__packed` as the name, > so would be interested if it still reproduces. > > > On Wed, Nov 26, 2025 at 3:15 PM Haochen Jiang <[email protected]> > wrote: > >> On Linux/x86_64, >> >> 1c9d93bfcd172c156fd0e94ea9990569bf46aeda is the first bad commit >> commit 1c9d93bfcd172c156fd0e94ea9990569bf46aeda >> Author: Tomasz Kamiński <[email protected]> >> Date: Wed Nov 19 10:29:18 2025 +0100 >> >> libstdc++: Hashing support for chrono value classes [PR110357] >> >> caused >> >> FAIL: std/ranges/adaptors/93978.cc -std=gnu++26 (test for excess errors) >> >> with GCC configured with >> >> ../../gcc/configure >> --prefix=/export/users3/haochenj/src/gcc-bisect/master/master/r16-5613/usr >> --enable-clocale=gnu --with-system-zlib --with-demangler-in-ld >> --with-fpmath=sse --enable-languages=c,c++,fortran --enable-cet >> --without-isl --enable-libmpx x86_64-linux --disable-bootstrap >> >> To reproduce: >> >> $ cd {build_dir}/x86_64-linux/libstdc++-v3/testsuite && make check >> RUNTESTFLAGS="conformance.exp=std/ranges/adaptors/93978.cc >> --target_board='unix{-m32}'" >> $ cd {build_dir}/x86_64-linux/libstdc++-v3/testsuite && make check >> RUNTESTFLAGS="conformance.exp=std/ranges/adaptors/93978.cc >> --target_board='unix{-m32\ -march=cascadelake}'" >> $ cd {build_dir}/x86_64-linux/libstdc++-v3/testsuite && make check >> RUNTESTFLAGS="conformance.exp=std/ranges/adaptors/93978.cc >> --target_board='unix{-m64}'" >> $ cd {build_dir}/x86_64-linux/libstdc++-v3/testsuite && make check >> RUNTESTFLAGS="conformance.exp=std/ranges/adaptors/93978.cc >> --target_board='unix{-m64\ -march=cascadelake}'" >> >> (Please directly reply to this email for question about this report.) >> (If you met problems with cascadelake related, disabling AVX512F in >> command line might save that.) >> (However, please make sure that there is no potential problems with >> AVX512.) >> >>
