So..... This is the sort of post that won't mean much to most people, but I think about three people who will be thankful. Right now, Phoronix Test Suite seems to be hard-coded for Intel. This means running many dependencies using x86 binaries and having Homebrew installed as x86 as well as arm64. The jump-off point for me was Phoronix Test Suite #110993 .

For a quick summary, brew installs to /usr/local/ on x86 and /opt/homebrew/ on macOS. However, if you run, say, the pts/webp on an ARM64 Mac, regardless if you have already installed libjpeg, it will complain: 

% phoronix-test-suite debug-run webp       

 Evaluating External Test Dependencies ............................................................................................................................

The following dependencies are needed and will be installed: 

- jpeg

This process may take several minutes.
Warning: jpeg 9f is already installed and up-to-date.
To reinstall 9f, run:
 brew reinstall jpeg

There are dependencies still missing from the system:
- JPEG Library

1: Ignore missing dependencies and proceed with installation.
2: Skip installing the tests with missing dependencies.
3: Re-attempt to install the missing dependencies.
4: Quit the current Phoronix Test Suite process.
Missing dependencies action: 3

The following dependencies are needed and will be installed: 

- jpeg

This error message gives you the option to reinstall the missing dependencies. Seems great, until you try to use it. If you select option 3, if you already have the dependency installed, it'll report it as installed 

 his process may take several minutes.
Warning: jpeg 9f is already installed and up-to-date.
To reinstall 9f, run:
 brew reinstall jpeg

Phoronix Test Suite v10.8.4

 Installed:     pts/webp-1.4.0

After the test attempts to run, we can se that the dependency for jpeg is reporting as not compiled, and thus the test file for jpeg cannot to be read.

Test Run Directory: /Users/greg/.phoronix-test-suite/installed-tests/pts/webp-1.4.0/


Test Run Command: ./webp -v -mt

JPEG support not compiled. Please install the libjpeg development package before building.
Error! Could not process file sample-photo-6000x4000.JPG
Error! Cannot read input picture file 'sample-photo-6000x4000.JPG'

You'll need to go into /opt/homebrew/opt/phoronix-test-suite/, the version number, 10.8.4 then open /share/phoronix-test-suite/pts-core/objects/client/pts_external_dependencies.php and locate the $possible_paths declarations (there should be two in all), and add to the array the following, '/opt/homebrew/opt/', '/opt/homebrew/include/', '/opt/homebrew/', .

This will now enable Phoronix to search for the ARM64 binaries.

You may still encounter issues, I found that I needed to declare in the terminal session the following to run the webp test as libjpeg:

export LDFLAGS="-L/opt/homebrew/opt/jpeg/lib"
export CPPFLAGS="-I/opt/homebrew/opt/jpeg/include"
export PKG_CONFIG_PATH="/opt/homebrew/opt/jpeg/lib/pkgconfig"
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