ldionne added a comment. In https://reviews.llvm.org/D35388#1167315, @thomasanderson wrote:
> In https://reviews.llvm.org/D35388#1167305, @ldionne wrote: > > > ABI-wise, I think this change is OK. Indeed, if `__type_visibility__` is > > not supported, we're already marking the base template as > > `__visibility__("default")`, so marking the extern template declaration > > with `__visibility__("default")` is not a problem. If `__type_visibility__` > > is supported, then there's no change in behavior. So I think there is no > > change in behavior either way, and I'm actually wondering why > > @thomasanderson wants this change in if the behavior is always the same. > > Perhaps I am missing something? > > > It's been a while, but IIRC this fixes the Chromium build with gcc and > libc++, since std::vector_base_common<true>::__throw_length_error() wasn't > getting exported otherwise. Ah, well of course! That's because I assumed that `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS` was always used on extern template declarations where the base template had been declared with `_LIBCPP_TEMPLATE_VIS`, which isn't true for `__vector_base_common`. > See the comment in the Chromium source code: > > https://cs.chromium.org/chromium/src/buildtools/third_party/libc%2B%2B/BUILD.gn?rcl=0dd5c6f980d22be96b728155249df2da355989d9&l=88 > > And also this CL https://reviews.llvm.org/D35326 I would think that both this change and https://reviews.llvm.org/D35326 are good. https://reviews.llvm.org/D35388 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
