when unique_ptr implements pimpl, assignment in a class declaration also results in: error: invalid application of ‘sizeof’ to incomplete type ‘***’
excuse me, when I was implementing pimpl with std::unique_ptr, I accidentally found that when I set pimpl to nullptr in the header file, gcc(version 9.4.0,14.1.0) cannot be compiled. But cl.exe (version 19.20.27508.1) can be compiled, cancel the assignment, then can be compiled, I tried to find the possibility, but finally did not have an answer
The code is as follows: