https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59874
--- Comment #4 from Manuel Lauss <manuel.lauss at googlemail dot com> --- (In reply to Uroš Bizjak from comment #3) > (In reply to Manuel Lauss from comment #2) > > > I've run into this issue with current gcc-6-branch while building for > > example qt-5.7. gcc-5-branch can build this source just fine: > > __builtin_clzs and __builtin_ctzs are internal x86 builtins and were > recently removed. You should use __lzcnt16 and __tzcnt_u16 intrinsics. Done, > > > return v ? __builtin_ctzs(v) : 16U; > > return v ? __builtin_clzs(v) : 16U; > > You don't need this, the instruction does exactly the above. without it there are errors with missing constexprs. Thanks, I've successfully built qt-5.7 with updated source.
