RFR: 8346888: [ubsan] block.cpp:1617:30: runtime error: 9.97582e+36 is outside the range of representable values of type 'int'

[Dean Long]

On Wed, 12 Mar 2025 07:55:03 GMT, Damon Fenacci <dfenacci at openjdk.org> wrote:

>> Also, to compute `from_pct`, we end up multiplying and then dividing by the same value `b->_freq`, which cancel out and simplify to `100 * b->succ_prob(j)`.  Furthermore, succ_prob() should always return a value between 0.0 and 1.0, so the real problem is probably only `to_pct` and very small values of `target->_freq`.
>
>> Do you think those high values are not expected ?
> 
> Sorry, my mistake. As @dean-long pointed out they are to be expected with very small values of `target->_freq`

I think it would still be helpful to understand what kind of situations cause these extreme values.  I know there are places where we have to adjust for problematic 0 counts, so I'm wondering if something like that is happening here.

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PR Review Comment: https://git.openjdk.org/jdk/pull/23962#discussion_r1992256072