[Bug middle-end/46488] [4.5 regression] server/core_filters.c from apache httpd 2.2.17 miscompiled at -O3

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46488

--- Comment #18 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2010-11-28 
13:21:51 UTC ---
Using

#define APR_RING_SENTINEL(hp, elem, link)                \
    (struct elem *)((char *)(hp) - APR_OFFSETOF(struct elem, link))

should be safer wrt strict aliasing.