Is this FE bug or am I missing something?

Igor Shevlyakov
Mon Sep 12 19:41:00 GMT 2016

Well, my concern is not what happens with overflow (which in second
case -fsanitize=undefined will address), but rather consistency of
that 2 cases.

p[x+1] generates RTL which leads to better generated code at the
expense of leading to overflow, while p[1+x] never overflows but leads
to worse code.
It would be beneficial to make the behaviour consistent between those 2 cases.

Thanks for your input

On Mon, Sep 12, 2016 at 12:51 AM, Marc Glisse <> wrote:
> On Sun, 11 Sep 2016, Igor Shevlyakov wrote:
>> Small sample below fails (at least on 6.1) for multiple targets. The
>> difference between two functions start at the very first tree pass...
> You are missing -fsanitize=undefined (and #include <stdlib.h>).
> Please use the mailing list next time.
> --
> Marc Glisse

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