Spack environment based build automation

[kaanolgu]

This Spack environment based build bash script would help us to move between testbeds rapidly.

The prerequisites:

Clone Spack
Latest versions of GCC (tested with 14.3.0) 

The usage:

./build.sh [cpu/gpu] [debug/release] 

The [debug/release] is optional if nothing is provided it would be automatically Release

[kaanolgu]

This should be edited by the user. What could be the best way to retrieve this information? a directory above the x3d2 folder maybe ?

[ia267]

I don't think we should add this to the code repo:

• The build.sh currently requires spack dir to be in a certain hardcoded dir - additional script changes needed to get it to work or moving of directories if spack not in the standard dir.
• The build.sh doesn't all all the cmake flags we have, we could add them, but if we add more flags we'll have to update the script. There's a risk that someone may unpdate CmakeLists.txt but not update spack script
• Most HPCs will have these packages installed, in which case it'll just be easier to just load modules and run the cmake command. The use case here is I guess for someone who wants to build on their own machine that may not have packages and will make it easier. I think for these users we could provide a README file
• Cloning spack repo (200MB) - extra friction even though you only do it once

I think it will be useful to add a section in contributor guide with an example for a combined GPU/CPU spack.yml file, and explaining how to use it - could save time for quick tests