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Re: are statically allocated structs always aligned to a machine word on x86/x86_64?
- From: Segher Boessenkool <segher at kernel dot crashing dot org>
- To: Jonathan Wakely <jwakely dot gcc at gmail dot com>
- Cc: john smith <wempwer at gmail dot com>, gcc-help <gcc-help at gcc dot gnu dot org>
- Date: Sun, 23 Aug 2015 10:19:13 -0500
- Subject: Re: are statically allocated structs always aligned to a machine word on x86/x86_64?
- Authentication-results: sourceware.org; auth=none
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On Sun, Aug 23, 2015 at 02:49:17PM +0100, Jonathan Wakely wrote:
> On 23 August 2015 at 12:05, Segher Boessenkool wrote:
> > On Sun, Aug 23, 2015 at 12:15:56AM +0100, Jonathan Wakely wrote:
> >> because alignments must be a power of 2.
> >
> > That is true in C++, but not true in C or even POSIX afaics?
>
> C11 §6.2.8
>
> "Every valid alignment value shall be a nonnegative integral power of two."
Ah, that is hidden deep in /4, I didn't see it :-) This is new
in C11 it seems?
And sorry for wandering off-topic.
Segher