[Vm-dev] latest vm 64bits crashes my image

Eliot Miranda eliot.miranda at gmail.com
Mon Jan 9 19:52:41 UTC 2017


On Mon, Jan 9, 2017 at 11:26 AM, Eliot Miranda <eliot.miranda at gmail.com>
wrote:

> Hi All, Hi Nicolas, Hi Esteban,
>
>     ok, I see the problem.  It's a Slang bug. With current Slang and
> current sources, turning off the remembered bit clears half the header word
> on 64-bits.  i.e. setIsRememberedOf: referrer to: false translates to
>
> longAtput(referrer, (longAt(referrer)) & (~(1U <<
> (rememberedBitShift()))));
>
> not
>
> longAtput(referrer, (longAt(referrer)) & (~(1UL <<
> (rememberedBitShift()))));
>
> and 1U is an int.  No doubt this affects plenty of places in the VM, but
> for now the first symptom I see is the above, when remembered objects are
> scavenged and their remembered bit gets cleared.  I think the simple fix is
> that numeric constants should always be 1UL, or 1L, never 1U or 1, but I
> need to check the 32-bit sources too.
>

And always casting integer constants to at least long would be wrong
because Win64 is LLP64.  In fact the bug is
in generateBitInvert:on:indent:, which for bitnvert64, now that we handle
LLP64, needs to cast integer expressions to usqIntptr_t in 64-bits and to
unsigned long long in 32 bits.

Anyway, we should be able to fix this soon, certainly before tomorrow a.m.
> CET.
>

Normal service should be restored shortly ;-)

[sschurley broken /is/ normal service, hic! ed.]



> On Mon, Jan 9, 2017 at 5:02 AM, Esteban Lorenzano <estebanlm at gmail.com>
> wrote:
>
>>
>> (sent again with dump zipped)
>>
>> Hello,
>>
>> I just built a new VM for 64bits with latest sources and is crashing in
>> mac :(
>> Latest version I tested (and it was working) was based on
>> VMMaker.oscog-nice.1991 and is from november 2016.
>>
>> I’m adding the dump…
>>
>> any idea?
>>
>> Esteban
>>
>
> _,,,^..^,,,_
> best, Eliot
>



-- 
_,,,^..^,,,_
best, Eliot
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20170109/63df5102/attachment.html>


More information about the Vm-dev mailing list