[BZ #14134]
When converting IBM930 code with iconv(), if IBM930 code which
includes invalid multibyte character "0xffff" is specified, then
iconv() segfaults. This is easy to see using the following command:
echo '0x0e 0x43 0x8c 0xff 0xff 0x43 0xbd 0x43 0xbd' | xxd -r |
iconv -f IBM930 -t UTF-8