upstream link:
test case:
select space(date_add(101, INTERVAL (CAST(CHAR(‘1′ USING utf16) AS CHAR(1)))hour_second))
只影响5.5
根据crash的backtrace
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff4643700 (LWP 5874)]
0x0000000000706602 in get_interval_value (args=0x7fff84004e98, int_type=INTERVAL_HOUR_SECOND, str_value=<value optimized out>, interval=0x7ffff4640c40)
at /u01/project/PS5518/trunk/Percona-Server-5.5.18/sql/item_timefunc.cc:1460
1460 while (str != end && my_isspace(cs,*str))
在my_isspace(cs,*str)这里crash，my_isspace是一个宏：
#define my_isspace(s, c) (((s)->ctype+1)[(uchar) (c)] & _MY_SPC)
而对于utf16(my_charset_utf16_general_ci)或者utf32(my_charset_utf32_general_ci)类型的字符集，ctype为NULL(ctype-ucs2.c)
因此这里直接导致段错误。
Solution: convert input to ASCII before parsing,
and use the character set of the returned ASCII string.
.
