https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93989
--- Comment #5 from Michael de Lang <kingoipo at gmail dot com> --- Created attachment 47953 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47953&action=edit self-contained minimal test case I managed to reduce the test case to a single file, which also produces the two aforementioned error messages. Compile command: /home/oipo-unencrypted/Programming/gcc-build/./gcc/xg++ -shared-libgcc -B/home/oipo-unencrypted/Programming/gcc-build/./gcc -nostdinc++ -L/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/src -L/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/src/.libs -L/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/libsupc++/.libs -B/opt/gcc/10/x86_64-linux-gnu/bin/ -B/opt/gcc/10/x86_64-linux-gnu/lib/ -isystem /opt/gcc/10/x86_64-linux-gnu/include -isystem /opt/gcc/10/x86_64-linux-gnu/sys-include -B/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/./libstdc++-v3/src/.libs -fmessage-length=0 -fno-show-column -ffunction-sections -fdata-sections -g -O2 -D_GNU_SOURCE -DLOCALEDIR="." -nostdinc++ -I/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/include/x86_64-linux-gnu -I/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/include -I/home/oipo-unencrypted/Programming/gcc/libstdc++-v3/libsupc++ -I/home/oipo-unencrypted/Programming/gcc/libstdc++-v3/include/backward copy_assign_constexpr.cc -std=gnu++2a -fno-diagnostics-show-caret -fdiagnostics-color=never -Wl,--gc-sections -L/home/oipo-unencrypted/Programming/gcc-build/x86_64-linux-gnu/libstdc++-v3/src/filesystem/.libs -lm -o ./copy_assign_constexpr.exe
