[Bug c++/105798] New: Add new -Wshadow for data member

[tromey at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105798

            Bug ID: 105798
           Summary: Add new -Wshadow for data member
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tromey at gcc dot gnu.org
  Target Milestone: ---

While refactoring gdb -- changing a function to a method --
I accidentally introduced a self-assign, because the function
used local variables that had the same name as the class members.

gdb uses -Wshadow=local... I don't recall why but it seems like
it would be nice to have a level between 'local' and 'global'
so we could prevent locals from shadowing class members but
still not care about globals.

Test case:

struct x {
  int f;
  int y(int x) {
    int f = x;
    return f;
  }
};


This warns with -Wshadow but not -Wshadow=local.