No warning about duplicate values in enum

[Andrea Monaco via Gcc]

In gcc 8.3.0, compiling


enum
test
  {
    FIRST = 1,
    SECOND = 1,
    THIRD = 2
  };

int
main (void)
{
  return 0;
}


generates no warning even with -Wextra.  That hit me today, because I
had a large enum with many explicitly assigned constants and I
accidentally used the same value twice, which is an obvious source of
problems.



Andrea Monaco