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Re: PowerPC malloc alignment
- From: Daniel Jacobowitz <drow at false dot org>
- To: Wolfram Gloger <wmglo at dent dot med dot uni-muenchen dot de>
- Cc: roland at redhat dot com, jakub at redhat dot com, libc-alpha at sourceware dot org, sjmunroe at us dot ibm dot com
- Date: Thu, 1 Nov 2007 12:24:14 -0400
- Subject: Re: PowerPC malloc alignment
- References: <20071031205240.GA30110@caradoc.them.org> <20071031212316.GU2896@sunsite.mff.cuni.cz> <20071031213648.769884D04AE@magilla.localdomain> <20071101161745.31969.qmail@md.dent.med.uni-muenchen.de>
On Thu, Nov 01, 2007 at 04:17:45PM -0000, Wolfram Gloger wrote:
> But how did these long double types come about? Wheren't they
> available in old PowerPC versions (if yes, then the alignment should
> have been 16 from the very start), or only with "-mlong-double-128"?
>
> IOW, why does this problem suddenly appear?
The introduction of 128-bit long double is a relatively recent ABI
change (within the past two years, and not entirely universal yet).
16-byte vectors are also relatively new, though I suspect people
writing vector code have been trained to use posix_memalign to avoid
trouble. Before either of those, 64-bit was clearly the right
alignment.
--
Daniel Jacobowitz
CodeSourcery