[Bug c++/89596] [8 regression] Multiple templated conversion operators result in compilation error

[jleahy+gcc at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89596

--- Comment #1 from jleahy+gcc at gmail dot com ---
This only happens with -std=c++17, without -std=c++17 the code fails to
compile.