[Bug c++/84075] Template parameter not resolved: invalid application of ‘sizeof’ to incomplete type ‘boost::serialization::U’

[gael.guennebaud at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84075

--- Comment #10 from Gael Guennebaud <gael.guennebaud at gmail dot com> ---
I created a simplified example that has no dependencies at all:

https://godbolt.org/z/uIy1Uu

You can workaround the compilation issue by either:

#1 - commenting line 16 and uncommenting line 15,
     i.e.,  by by-passing some indirection.

#2 - commenting line 16 and uncommenting line 21,
     i.e., by removing the default value of the second templated parameter of
Base<>.

Hope it will help fixing the issue.