[Bug c++/123618] New: [reflection] annotation on void parameter accepted

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123618

            Bug ID: 123618
           Summary: [reflection] annotation on void parameter accepted
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mpolacek at gcc dot gnu.org
  Target Milestone: ---

We should reject

```
void f([[=1]] void) {}
```

since the void does not declare a function parameter.