-malign-double

[Barry Smith]

    Good point, I have removed it.

    I put it in because I wanted an easy way to test that PETSc double  
arrays are always 8 byte aligned (and the unaligned struct values were  
giving me lots of false alarms).

    I guess we can test for double align on x86_64 systems.

    Barry

The IBM BlueGene doesn't like 4 byte aligned doubles and sends a bus  
error after a certain number are generated, Thus I was motivated to  
make PETSc a bit clearer on that.


On Nov 12, 2009, at 9:29 AM, Lisandro Dalcin wrote:

> On Wed, Nov 11, 2009 at 11:02 PM, Barry Smith <bsmith at mcs.anl.gov>  
> wrote:
>>
>>  Satish,
>>
>>    gcc supports the option  -malign-double on some systems. Please  
>> add it to
>> the flags that configure checks for c and c++ and have it added if it
>> exists.
>>
>
> Definitely -1. Why are you asking for this? On x86_64 this is the
> default. In i386, this flag is likely going to break ABI's.
>
>
> -- 
> Lisandro Dalcín
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