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Re: Opportunistic garbage collection
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From: |
Paul Eggert |
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Subject: |
Re: Opportunistic garbage collection |
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Date: |
Thu, 25 Apr 2019 15:14:16 -0700 |
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User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 |
On 4/25/19 11:18 AM, Stefan Monnier wrote:
>
>> This assumes byte_ct is not narrower than EMACS_INT, which isn't true on
>> 32-bit platforms --with-wide-int.
> Does it? My understanding is that if byte_ct is narrower what happens
> is:
>
> 1- consing_since_gc is widened to EMACS_INT, preserving the mathematical
> value.
> 2- multiplication with `fact`.
And since that's signed integer multiplication, it can overflow with
undefined behavior.