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Re: 128-bit integer - nonsensical documentation?
- From: Jonathan Wakely <jwakely dot gcc at gmail dot com>
- To: Kostas Savvidis <ksavvidis at gmail dot com>
- Cc: gcc-help <gcc-help at gcc dot gnu dot org>
- Date: Wed, 26 Aug 2015 13:22:13 +0100
- Subject: Re: 128-bit integer - nonsensical documentation?
- Authentication-results: sourceware.org; auth=none
- References: <1B1111BE-E274-4C80-8189-22B78D77647A at gmail dot com>
On 26 August 2015 at 12:04, Kostas Savvidis wrote:
> The online documentation contains the attached passage as part of the "C-Extensionsâ chapter. There are no actual machines which have an " integer mode wide enough to hold 128 bitsâ as the document puts it.
It's not talking about machine integers, it's talking about GCC
integer modes. Several targets support that.
> This would be a harmless confusion if it didnât go on to say ââ long long integer less than 128 bits wideâ (???!!!) Whereas in reality "long long intâ is 64 bits everywhere i have seen.
Read it more carefully, it says you can't express an integer constant
of type __int128 on such platforms.
So you can't write __int128 i =
999999999999999999999999999999999999999999999999999999999999;