[Patch] Testcase for vfprintf bug

[Jeff Law]

On 05/24/2012 12:36 PM, Roland McGrath wrote:
> The new test looks fine and since it's simpler than the one in the bug
> attachment that's better anyway.
Good :-)


   But real good trick finding a system
> that "pre-dates printf hooks" since IIRC the printf.h interface
> actually pre-dates the %n$ support by a few years (and it might well
> pre-date Linux, in fact).
More correctly, the system continues to use the fast path even with a 
printf hook installed.  It's missing this hunk:

   /* Use the slow path in case any printf handler is registered.  */
   if (__builtin_expect (__printf_function_table != NULL
                         || __printf_modifier_table != NULL
                         || __printf_va_arg_table != NULL, 0))
     goto do_positional;

Sorry for the confusion.

jeff