With help from Paul Eggert, Carlos O'Donell, and Roland McGrath.
* stdio-common/printf-parse.h (read_int): Change return type to
'int', return -1 on INT_MAX overflow.
* stdio-common/vfprintf.c (vfprintf): Validate width and precision
against overflow of INT_MAX. Set errno to EOVERFLOW when 'done'
overflows INT_MAX. Check for overflow of in-format-string precision
values properly. Use EOVERFLOW rather than ERANGE throughout. Use
SIZE_MAX not INT_MAX for integer overflow test.
* stdio-common/printf-parsemb.c: If read_int signals an overflow,
skip the construct in the format string but do not record anything.
* stdio-common/bug22.c: Adjust to test both width/prevision
INT_MAX overflow as well as total length INT_MAX overflow. Check
explicitly for proper errno values.
