Re: [PATCH] Fix PR61657 (undefined behavior in loop-iv.c)

[Jeff Law]

On 08/21/2015 07:40 AM, Markus Trippelsdorf wrote:
bootstrap-ubsan shows:
  loop-iv.c:2626:14: runtime error: signed integer overflow: 
9223372036854775806 - -9223372036854775808 cannot be represented in type 'long 
int'
Fixed by moving the variables in question from signed to unsigned.

Bootstrapped and tested on ppc64le.
OK for trunk and gcc-5 branch?

Thanks.

2015-08-21  Markus Trippelsdorf  <mar...@trippelsdorf.de>

        PR rtl-optimization/61657
        * loop-iv.c (iv_number_of_iterations): Declare up and down as
        unsigned. Remove superflous uint64_t cast.
OK for trunk.

AFAIK this isn't a regression, so Richi, Jakub or Joseph ought to 
explicitly ack for the gcc-5 branch.

jeff