Depend on portable-atomic-* only if the target has no OS

[stefunctional]

Issues:

N/A

Description of changes:

This makes the portable-atomic* dependencies conditional on the target not having an OS.

Call-outs:

N/A

Testing:

Built

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f0ae87b) 91.77% compared to head (8e75f71) 91.79%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #65      +/-   ##
==========================================
+ Coverage   91.77%   91.79%   +0.01%     
==========================================
  Files         169      169              
  Lines       30807    30807              
==========================================
+ Hits        28273    28278       +5     
+ Misses       2534     2529       -5     

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[stefunctional]

@mgeisler, may you check if the latest main resolves your issue regarding the portable-atomic* dependencies?

[mgeisler]

Hi @stefunctional, wow that's very nice!

If I read this correctly, it means that the dependency will only be added bare-metal platforms? And perhaps Wasm as well? I'll test it out in AOSP again in a few days — the version I grabbed some weeks ago is okay for me to test with right now.

[stefunctional]

Hi @mgeisler,

Right, portable-atomic* would only be used on targets that don't have an OS. It's not clear to me what that means for WASM.

There's a more precise cfg to test for atomic support in core at compile-time, so I opened #66 for that.