[Bug c++/121329] New: There are some errors about std::nullopt

[q1210081098 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121329

            Bug ID: 121329
           Summary: There are some errors about std::nullopt
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: q1210081098 at gmail dot com
  Target Milestone: ---

I wrote a code hoping to use the max_element function to get the maximum value
in a vector and return it.

https://gcc.godbolt.org/z/19nr6hP5x

You can see that a bug occurred, but when I removed the processing of null
values, the bug disappeared

https://gcc.godbolt.org/z/esEbWKMG8

std::nullopt may cause this problem