[Bug c/57773] New: -Wpedantic incorrect warning for enum bit-field

[eggert at gnu dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57773

            Bug ID: 57773
           Summary: -Wpedantic incorrect warning for enum bit-field
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: eggert at gnu dot org

Given this program in the file t.c:

  enum e { zero };
  struct { enum e field: 2; } s;

The command "gcc -Wpedantic -S t.c" outputs:

  t.c:2:15: warning: type of bit-field 'field' is a GCC extension [-Wpedantic]
  struct { enum e field: 2; } s;

This diagnostic should not be output.  -Wpedantic is supposed to
generate only diagnostics required by the standard.  But this
diagnostic is not required by C99 or by C11, since these standards
allow this GCC extension and do not require a diagnostic if the
extension is used.  And the diagnostic is not required by C89 since no
constraint is violated.