[racket-dev] errors from `force`

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Wed Aug 29 10:34:02 EDT 2012

On Wed, Aug 29, 2012 at 9:20 AM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> At Mon, 27 Aug 2012 17:36:42 -0400, Sam Tobin-Hochstadt wrote:
>> Since I've made the Typed Racket tests run in parallel, there have
>> been intermittent errors in DrDr, like this:
>>   http://drdr.racket-lang.org/25278/collects/tests/typed-racket/run.rkt
>> I'm not sure exactly what could be causing this -- I don't think
>> promises should ever fail to `force`.  Might there be something I'm
>> doing wrong, or is this a bug in promises?
> I've fixed a race in `delay/sync' that I think could cause the error.

Unfortunately, this DrDr build with your fix still has the problem:

I've never been able to reproduce this bug on my machine, though.
sam th
samth at ccs.neu.edu

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