[Bug tree-optimization/70267] ICE on valid code at -O1 and above on x86_64-linux-gnu in propagate_necessity, at tree-ssa-dce.c:924

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70267

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
We ICE in propagate_necessity because it can't digest
# VUSE <.MEM_3>
f.0_4 = (struct Foo *) D.2296;
which is 
(gdb) p gimple_code(stmt)
$2 = GIMPLE_ASSIGN
but
(gdb) p gimple_assign_single_p (stmt)
$3 = false
thus we end up in the gcc_unreachable (); branch there.