topic Re: Does MKL affect the intrinsic operations? in Intel® oneAPI Math Kernel Library

Does MKL affect the intrinsic operations?

Hongwei_Zhou — Fri, 08 May 2009 23:58:21 GMT

HI

I got very strange behavior of MKL. With MKL linked in my program, in the debug module I monitored the result for
one line of pure fortran code becomes NaN. Linked to source code of blas instead of MKL, the result of that line of fortran code is normal.

I am wondering how MKL infulence the behavior of the program even on the intrinsic operation like mulitplicaiton.

Thanks.

Re: Does MKL affect the intrinsic operations?

Hongwei_Zhou — Sat, 09 May 2009 00:03:32 GMT

Quoting - optistruct

This behavior only happens on 32 bit RH Linux machine.

Re: Does MKL affect the intrinsic operations?

TimP — Sat, 09 May 2009 01:18:25 GMT

One possibility is that passing bad data to an MKL function could cause it to exceed array bounds and write garbage where you didn't expect it. Setting debug mode in your program doesn't set it in MKL.

Re: Does MKL affect the intrinsic operations?

Gennady_F_Intel — Sun, 10 May 2009 19:07:34 GMT

Quoting - tim18

Optistruct, probably tim is right, but for investigation the problem - can you get us the test case?