[Bug c/103492] 2 * new warnings in clang build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103492

--- Comment #8 from Martin Liška <marxin at gcc dot gnu.org> ---
Even simpler test-case:

struct A
{
  unsigned int val: 1;
};

int foo(struct A *a)
{
  switch (a->val)
  {
    case 0:
      return 123;
    case 1:
      return 456;
  }
}