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Date: Mon, 23 May 2011 10:07:21 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH] qemu: json: Fix parsing of integers >=
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To: Markus Armbruster <armbru@redhat.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>, "Richard W.M. Jones" <rjones@redhat.com>, qemu-devel@nongnu.org

On 05/23/2011 09:29 AM, Markus Armbruster wrote:
> Anthony Liguori<anthony@codemonkey.ws>  writes:
>
> JavaScript's implementation of JSON sets limits on the range of numbers,
> namely they need to fit into IEEE doubles.
>
> Our implementation sets different limits.  IIRC, it's something like
> "numbers with a fractional part or an exponent need to fit into IEEE
> doubles, anything else into int64_t."  Not exactly the acme of elegance,
> either.  But it works for us.

In order to be compatible with JavaScript (which I think is necessary to 
really satisfy the spec), we just need to make sure that our integers 
are represented by at least 53-bits (to enable signed integers) and 
critically, fall back to floating point representation to ensure that we 
round instead of truncate.

Regards,

Anthony Liguori

>