[Bug rtl-optimization/45472] [4.5/4.6 Regression] ICE: in move_op_ascend, at sel-sched.c:6124 with -fselective-scheduling2

[matz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45472

--- Comment #10 from Michael Matz <matz at gcc dot gnu.org> 2010-10-18 15:58:26 UTC ---
One idea we had was that this is all frontends business anyway, and hence
it should (if it so desires) simply create volatile MEM_REFs for references
to half-volatile objects.  That alone would result in the copy statement
being marked volatile, and would also (I guess, haven't checked) do the right
thing in expand.

So, if we (the frontend) decide that accesses to objects containing volatile
subobjects should itself be regarded as volatile, then generating the right
kind of MEM_REF would already provide that.