[Bug tree-optimization/78810] [7 Regression] Optimized out volatile memory access

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78810

--- Comment #2 from rguenther at suse dot de <rguenther at suse dot de> ---
On Fri, 16 Dec 2016, marxin at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78810
> 
> --- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
> Sorry, correct wording is that Ruby 2.3 does not survive its regression tests.

Did you analyze why?  vparser is unused here ...  it looks like ruby
is maybe trying to avoid a tail/sibling call here?

That said, the optimization is perfectly valid.