GCC 4.5.0 20090709. (IIRC, there was no such ICE when compiling with 20090702.)

gcc -S -O1 -finline-small-functions -foptimize-sibling-calls -march=i686 bug.c

bug.c:12:1: internal compiler error: in purge_dead_edges, at cfgrtl.c:2323

bug.c:
================================
extern int baz(void), zab(void);

char bar(void)
{
    int i = 1;
    return *(char *)&i;
}

void foo(void)
{
   (bar() ? baz : zab)();
}
================================