[Bug middle-end/67442] [5/6 Regression] GCC 5.2.0 on x86_64 creates invalid address on specific array index calculation through pointer

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67442

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Ok, truncation also should work, thus

  gcc_assert (prec <= pcst.get_precision ());

(trying to see how far bootstrap goes with that)