Hello,

This error occurs because the float-128 data type is not supported on Apple ARM chips.

You can try running the nightly dev build for Mac available here: https://surfer.nmr.mgh.harvard.edu/pub/dist/freesurfer/dev/freesurfer-macOS-...

But please note that this is an unstable and not an official release.

Best, Jackson ________________________________ From: freesurfer-bounces@nmr.mgh.harvard.edu freesurfer-bounces@nmr.mgh.harvard.edu on behalf of Martin Juneja mj70481@gmail.com Sent: Wednesday, February 7, 2024 5:05 PM To: Iglesias Gonzalez, Juan E. JIGLESIASGONZALEZ@mgh.harvard.edu; Freesurfer support list freesurfer@nmr.mgh.harvard.edu Subject: [Freesurfer] Synthsr command !

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Dear Juan and FreeSurfer developers,

I am trying to run the mri_synthsr command on a MacPro M2 Max chip (OS 13.6.4) - but somehow, I am getting the following error when I try to run this command. I am using FreeSurfer's 7.4.1 version.

Illegal instruction: 4

I would greatly appreciate any help in getting this resolved.

Thanks.