https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90137
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |WAITING Last reconfirmed| |2019-04-18 Ever confirmed|0 |1 --- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- It works for me with FSF GCC 8.3.0. The attached testcase instead emits > /space/rguenther/install/gcc-8.3/bin/g++ main.cpp -I. -S -std=gnu++11 -g > -Wall -W -Wextra -fPIC In file included from /home/space/rguenther/install/gcc-8.3/include/c++/8.3.0/memory:80, from using.h:4, from main.cpp:1: /home/space/rguenther/install/gcc-8.3/include/c++/8.3.0/bits/unique_ptr.h: In instantiation of ‘void std::default_delete<_Tp>::operator()(_Tp*) const [with _Tp = DerivedPrivate]’: /home/space/rguenther/install/gcc-8.3/include/c++/8.3.0/bits/unique_ptr.h:274:17: required from ‘std::unique_ptr<_Tp, _Dp>::~unique_ptr() [with _Tp = DerivedPrivate; _Dp = std::default_delete<DerivedPrivate>]’ using.h:14:7: required from here /home/space/rguenther/install/gcc-8.3/include/c++/8.3.0/bits/unique_ptr.h:79:16error: invalid application of ‘sizeof’ to incomplete type ‘DerivedPrivate’ static_assert(sizeof(_Tp)>0, ^~~~~~~~~~~