Re: [PATCH] [20/45] x86_64: Use 8 byte stack alignment whenpossible

[Dave Jones]

On Sat, Sep 22, 2007 at 12:34:31AM +0200, Andi Kleen wrote:
 > On Friday 21 September 2007 23:13, Dave Jones wrote:
 > > On Fri, Sep 21, 2007 at 10:45:02PM +0200, Andi Kleen wrote:
 > >  > Kernel doesn't use SSE2, so it doesn't need 16 byte alignment. Also
 > >  > the stack can be already unaligned so letting the compiler align
 > >  > is useless. This may make some stack frames smaller.
 > >  > Only works with very recent gcc 4.3
 > >
 > > My gcc 4.1.2 from Fedora 7 (with who knows what backported)
 > > references this in its manpage. How was it broken before 4.3 ?
 > 
 > Try it. It is rejected by the compiler in 64bit mode.

Ah yes, it fails if not between 4 & 12, but the call cc-option
catches that.  Looks fine to me.

	Dave

-- 
http://www.codemonkey.org.uk
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