Date: Fri, 21 Apr 2017 13:16:44 +1000 (EST) From: Bruce Evans <brde@optusnet.com.au> To: Cy Schubert <Cy.Schubert@komquats.com> Cc: Michael Tuexen <tuexen@freebsd.org>, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r317208 - head/sys/netinet Message-ID: <20170421131041.G966@besplex.bde.org> In-Reply-To: <201704210143.v3L1h99s037727@slippy.cwsent.com> References: <201704210143.v3L1h99s037727@slippy.cwsent.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 20 Apr 2017, Cy Schubert wrote: Please trim quotes. > In message <201704201919.v3KJJYko052651@repo.freebsd.org>, Michael Tuexen > write > s: [>> ... 5 lines trimmed] >> Log: >> Syncoockies can be used in combination with the syncache. If the cache >> overflows, syncookies are used. [>> ... 16 lines trimmed] >> Modified: head/sys/netinet/tcp_syncache.c >> ============================================================================= >> = >> --- head/sys/netinet/tcp_syncache.c Thu Apr 20 19:14:52 2017 (r31720 >> 7) >> +++ head/sys/netinet/tcp_syncache.c Thu Apr 20 19:19:33 2017 (r31720 >> 8) >> @@ -260,6 +260,7 @@ syncache_init(void) >> &V_tcp_syncache.hashbase[i].sch_mtx, 0); >> V_tcp_syncache.hashbase[i].sch_length = 0; >> V_tcp_syncache.hashbase[i].sch_sc = &V_tcp_syncache; >> + V_tcp_syncache.hashbase[i].sch_last_overflow = INT64_MIN; > ... > This line produced the following on i386: > > /opt/src/svn-current/sys/netinet/tcp_syncache.c:263:50: error: implicit > conversion from 'long long' to 'time_t' (aka 'int') changes value from > -9223372036854775808 to 0 [-Werror,-Wconstant-conversion] > V_tcp_syncache.hashbase[i].sch_last_overflow = INT64_MIN; > ~ ^~~~~~~~~ > ./x86/_stdint.h:91:41: note: expanded from macro 'INT64_MIN' > #define INT64_MIN (-0x7fffffffffffffffLL-1) > ~~~~~~~~~~~~~~~~~~~~~^~ > > Looks like it needs a time_t cast. A cast would just break the warning. INT64_MIN has nothing to do with time_t. The expression (time_t)INT64_MIN would be more obviously garbage since in the above it is not clear that sch_last_overflow has a type unrelated to the constant. INT64_MIN is also broken if time_t is 64 bits but unsigned. Then it is converted to half of plus infinity instead of the intended minus infinity. Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20170421131041.G966>