Hi Jonathan, I am sorry for the delay. The mailing lists libstdc++@gcc.gnu.org and gcc-patches@gcc.gnu.org have just too many emails, so your email got lost. I hope my changes still make sense to be included in GCC. Please, find my comments below. On Thu, May 11, 2023 at 3:57 PM Jonathan Wakely wrote: > > > On Mon, 27 Mar 2023 at 22:25, Weslley da Silva Pereira via Libstdc++ < > libstdc++@gcc.gnu.org> wrote: > >> Dear all, >> >> Here follows a patch that removes implicit type casts in std::complex. >> >> *Description:* The current implementation of `complex<_Tp>` assumes that >> `int, double, long double` are explicitly convertible to `_Tp`. Moreover, >> it also assumes that: >> >> 1. `int` is implicitly convertible to `_Tp`, e.g., when using >> `complex<_Tp>(1)`. >> 2. `long double` can be attributed to a `_Tp` variable, e.g., when using >> `const _Tp __pi_2 = 1.5707963267948966192313216916397514L`. >> >> This patch transforms the implicit casts (1) and (2) into explicit type >> casts. As a result, `std::complex` is now able to support more types. One >> example is the type `Eigen::Half` from >> https://eigen.tuxfamily.org/dox-devel/Half_8h_source.html which does not >> implement implicit type conversions. >> >> *ChangeLog:* >> libstdc++-v3/ChangeLog: >> >> * include/std/complex: >> > > Thank you for the patch. Now that we're in developement stage 1 for GCC > 14, it's time to consider it. > > You're missing a proper changelog entry, I suggest: > > * include/std/complex (polar, __complex_sqrt) > (__complex_pow_unsigned, pow, __complex_acos): Replace implicit > conversions from int and long double to value_type. > I agree with your proposal for the changelog. > You're also missing either a copyright assignment on file with the FSF > (unless you've completed that paperwork?), or a DCO sign-off. Please see > https://gcc.gnu.org/contribute.html#legal and https://gcc.gnu.org/dco.html > for more details. > Here is my DCO sign-off: *Copyright:* Signed-off-by: Weslley da Silva Pereira > > >> >> *Patch:* fix_complex.diff. (Also at >> https://github.com/gcc-mirror/gcc/pull/84) >> >> *OBS:* I didn't find a good reason for adding new tests or test results >> here since this is really a small upgrade (in my view) to std::complex. >> > > I don't agree. The purpose of this is to support std::complex for a > type Foo without implicit conversions (which isn't required by the standard > btw, only the floating-point types are required to work, but we can support > others as an extension). Without tests, we don't know if that goal has been > met, and we don't know if the goal continues to be met in future versions. > A test would ensure that we don't accidentally re-introduce code requiring > implicit conversions. > > With a suitable test, I think this patch will be OK for GCC 14. > > Thanks again for contributing. > > > *Tests:* See the attached file `test_complex_eigenhalf.cpp` *Test results:* - When using x86-64 GCC (trunk), I obtained compilation errors as shown in the attached text file. Live example at: https://godbolt.org/z/oa9M34h8P. - I observed no errors after applying the suggested patch on my machine. - I tried it with the flag `-Wall`. No warnings were shown. - My machine configuration and my GCC build information are displayed in the file `config.log` generated by the configuration step of GCC. Let me know if I need to do anything else. Thanks, Weslley -- Weslley S. Pereira