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Inconsistent results from Fortran programs on iMac 10.7.x and above

Lyndon_L_
Beginner
‎12-10-2013 06:25 PM
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Hi,

    I am having an annoying problem on iMac. The fortran programs was compiled with ifort 13 (also used -fp-model precise and -O3 ), the results from 10 runs are inconsistent.But running the same programs in a Macbook pro running 10.6.x are consistent.  It is really strange! I am not sure if I should blame Mac OSX or Intel compiler.

    Did anyone experience similar problem in Mac OSX 10.7 or above?

     Thanks

Cheers,

Lyndon.

 

 

 

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Steven_L_Intel1
Employee
‎12-11-2013 07:53 AM
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My guess would be that 10.7 is applying address space layout randomization. Try compiling with -align array32byte and see if things improve. See also the attached presentation.

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