Re: kernel: -mpreferred-stack-boundary=2 ??

[Matthew Dillon]

:> > Anyhow, I'll repeat it here - stack alignment does *not* break
:> > link-compatibility.  It does not change calling conventions, it just
:> > adds padding after the args to ensure that local variables can be
:> > predictably aligned.
:
:> So, how does aligning stackframes affect the inherently static property
:> of code size then?
:
:Instructions are inserted to perform that alignment (add padding).
:When the alignment is 2 (i.e. on 4-byte boundaries), no padding is
:required in typical cases.

    I can't think of a single case where the stack isn't inherently 
    4-byte aligned already, whether you use the option or not.  

    To whomever added the option:  Did you actually test to see that
    this option resulted in an improvement?  If not, I recommend removing
    it.  It sounds like unnecessary extra junk to me.

                                        -Matt
                                        Matthew Dillon 
                                        <[EMAIL PROTECTED]>


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