Thread: 9.6.10 build warning on Fedora 28
Hi,
Just noticed this on Fedora 28 box (GCC 8.1.1)
=====================================================================
pgbench.c: In function 'ParseScript':
pgbench.c:2640:20: warning: '__builtin___sprintf_chk' may write a terminating
nul past the end of the destination [-Wformat-overflow=]
sprintf(var, "$%d", cmd->argc);
^
In file included from /usr/include/stdio.h:862,
from ../../../src/include/c.h:81,
from ../../../src/include/postgres_fe.h:25,
from pgbench.c:34:
/usr/include/bits/stdio2.h:33:10: note: '__builtin___sprintf_chk' output
between 3 and 13 bytes into a destination of size 12
return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
__bos (__s), __fmt, __va_arg_pack ());
=====================================================================
Regards,
--
Devrim Gündüz
EnterpriseDB: https://www.enterprisedb.com
PostgreSQL Consultant, Red Hat Certified Engineer
Twitter: @DevrimGunduz , @DevrimGunduzTR
Attachment
On 9 August 2018 at 21:30, Devrim Gündüz <devrim@gunduz.org> wrote: > pgbench.c: In function 'ParseScript': > pgbench.c:2640:20: warning: '__builtin___sprintf_chk' may write a terminating > nul past the end of the destination [-Wformat-overflow=] > sprintf(var, "$%d", cmd->argc); > ^ > In file included from /usr/include/stdio.h:862, > from ../../../src/include/c.h:81, > from ../../../src/include/postgres_fe.h:25, > from pgbench.c:34: > /usr/include/bits/stdio2.h:33:10: note: '__builtin___sprintf_chk' output > between 3 and 13 bytes into a destination of size 12 > return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > __bos (__s), __fmt, __va_arg_pack ()); Generally, new warnings from newer compilers are not fixed in older branches. This particular warning was fixed in master in [1] and the discussion was in [2]. The warning is pretty false anyway since cmd->argc won't be negative. [1] https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=3a4b891964a531aa7d242a48fcd9e41379863ead [2] https://www.postgresql.org/message-id/304a21ab-a9d6-264a-f688-912869c0d7c6@2ndquadrant.com -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services