[Regression] test fails on 1.14.0-beta.2 (e627a2e6e 2016-11-16) with 'attempt to add with overflow'

[zetok]

Regressed from current and past stable (works on 1.13.0, 1.12.1) to current beta (1.14.0).

Error:

'attempt to add with overflow', ../src/libcore/ops.rs:263

Probably the code that beta handles wrongly: zetok/tox@0885d7e#diff-47bd9ee511e98206d1a2d1ad0809b219R1427

Works on stable rustc 1.13.0 (2c6933a 2016-11-07): https://travis-ci.org/zetok/tox/jobs/177605738#L960
Failed on beta rustc 1.14.0-beta.2 (e627a2e 2016-11-16): https://travis-ci.org/zetok/tox/jobs/177605739#L1137

[bluss]

This is intentional and it also was a regression that it stopped panicking (in 1.12 ?). It was fixed to not silently overflow in #36365

[arielb1]

Sure enough. Not a bug, but a fix to a regression introduced by MIR.