пт, 24 янв. 2020 г. в 01:04, Илья Шипицин <[email protected]>:
> > > пт, 24 янв. 2020 г. в 00:54, Willy Tarreau <[email protected]>: > >> On Fri, Jan 24, 2020 at 12:46:12AM +0500, ???? ??????? wrote: >> > > diff --git a/Makefile b/Makefile >> > > index 8399f6ca35..4757bc77e6 100644 >> > > --- a/Makefile >> > > +++ b/Makefile >> > > @@ -199,6 +199,7 @@ SPEC_CFLAGS += $(call >> cc-opt,-Wshift-negative-value) >> > > SPEC_CFLAGS += $(call cc-opt,-Wshift-overflow=2) >> > > SPEC_CFLAGS += $(call cc-opt,-Wduplicated-cond) >> > > SPEC_CFLAGS += $(call cc-opt,-Wnull-dereference) >> > > +SPEC_CFLAGS += $(call cc-opt,-Walloc-size-larger-than=-1) >> > > >> > >> > >> > CC src/cfgparse.o >> > src/cfgparse.c: In function 'check_config_validity': >> > src/cfgparse.c:3642:33: warning: product '2147483648 * 8' of arguments 1 >> > and 2 exceeds 'SIZE_MAX' [-Walloc-size-larger-than=] >> >> Pfff.... The only good news is that it takes -1 as SIZE_MAX. >> >> > newsrv->idle_orphan_conns = calloc((unsigned int)global.nbthread, >> > sizeof(*newsrv->idle_orphan_conns)); >> > >> > >> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> > src/cfgparse.c:3642:33: note: argument 1 in the range [2147483648, >> > 4294967295] >> (...) >> > why is it complaining about "product '2147483648 * 8" ? >> >> because calloc multiplies the two fields and gcc decided that the largest >> value we could possibly pass to the first one if we were as stupid as it >> is is 2147483648. Interestingly it took the largest negative value turned >> to positive and ignored the positive ones that can be turned to the second >> half that are negative if nbthread was negative. >> >> I really think this test is totally bogus and that there is no way to >> express it correctly. I mean, gcc only lets us use 8, 16, 32 or 64 bits. >> If you need to calloc a few megabytes, you'll be forced to apply a mask >> to the value just to shut it up, and *create* the overflow problem >> yourself >> when it didn't exist. >> >> Let's give up on this one if it doesn't cause too much trouble to you. >> Otherwise we might cheat doing this : >> >> calloc((unsigned short)global.nbthread, ...) >> >> But I really despise this given that we have to make the code wrong just >> to please this shitty compiler. >> > > > it was ubuntu 18.04 + gcc8, I'll try 19.10 + gcc9 > gcc9 produces the same warning > > >> >> Willy >> >
