# Embree problem with illegal instruction in ParaView 5.6.1

**URL:** https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070
**Category:** Development
**Created:** [June 18, 2019, 5:19pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070 "2019-06-18T17:19:23Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![joeh](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/j/ce7236/32.png) [@joeh](https://discourse.paraview.org/u/joeh)
#### Post date: [June 18, 2019, 5:19pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070/1 "2019-06-18T17:19:23Z")

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Hello,

I have found that there is a problem with compilation of ParaView 5.6.1 superbuild’s embree library  
for older Linux systems. The embree library seems to be calling avx instructions that are not present  
in these older systems. The superbuild for ParaView 5.6.0’s embree version did not have this problem.  
I have narrowed the issue down to the Superbuild\_5.6.1/projects/embree.cmake file and I have found that  
using the version from 5.6.0 instead fixes the issue. The problem has occurred with an Intel Xeon X5550 and an AMD Opteron 8378, but I expect that it will occur on many other older processors as well that lack AVX support. I have also verified that the binary for ParaView 5.6.1 (Linux) on Kitware’s website also has this issue present in it.

Thanks,

Joe Hennessey

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### Author: ![ben.boeckel](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.paraview.org/u/ben.boeckel)
#### Post date: [June 18, 2019, 5:23pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070/2 "2019-06-18T17:23:44Z")

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@Dave_DeMarle

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### Author: ![Dave\_DeMarle](https://discourse.paraview.org/user_avatar/discourse.paraview.org/dave_demarle/32/27_2.png) [@Dave\_DeMarle](https://discourse.paraview.org/u/Dave_DeMarle)
#### Post date: [June 18, 2019, 5:41pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070/3 "2019-06-18T17:41:01Z")

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Hey Joe.

This is the change that made AVX the minimum supported ISA.  
[https://gitlab.kitware.com/paraview/paraview-superbuild/commit/f3bbdc1d2a441ccf86498f16b5a818fc5709e6ca](https://gitlab.kitware.com/paraview/paraview-superbuild/commit/f3bbdc1d2a441ccf86498f16b5a818fc5709e6ca)  
I introduced it because MacOS no longer builds embree with SSE and AVX is quite old now.

For standalone builds you can set(embree\_BUILD\_ISA SSE2 SSE4D AVX AVX2) in your CMakeCache.txt to get back the SSE support.

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### Author: ![joeh](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/j/ce7236/32.png) [@joeh](https://discourse.paraview.org/u/joeh)
#### Post date: [June 18, 2019, 6:51pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070/4 "2019-06-18T18:51:05Z")

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CLASSIFICATION: UNCLASSIFIED

Dave,

Thanks, for the response. I think for now I will still  
need to build ParaView on our servers that lack AVX.

Joe

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### Author: ![ben.boeckel](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.paraview.org/u/ben.boeckel)
#### Post date: [June 21, 2019, 3:12pm UTC](https://discourse.paraview.org/t/embree-problem-with-illegal-instruction-in-paraview-5-6-1/2070/5 "2019-06-21T15:12:02Z")

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It seems that OSPRay needs AVX-minimum embree, so the way to do it on older CPUs is to disable OSPRay completely in the superbuild. (Based on information from @chuckatkins)