Build/Test for x86_64-pc-windows-gnullvm

[justsmth]

Issues:

Addresses: #696

Description of changes:

• Support target: x86_64-pc-windows-gnullvm
• Add CI testing for target.

Testing:

CI tests passing: https://github.com/aws/aws-lc-rs/actions/runs/14890896214/job/41822424105?pr=702

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.34%. Comparing base (c358484) to head (879bd98).
Report is 217 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #702      +/-   ##
==========================================
- Coverage   95.80%   92.34%   -3.46%     
==========================================
  Files          61       71      +10     
  Lines        8143     8972     +829     
  Branches        0     8972    +8972     
==========================================
+ Hits         7801     8285     +484     
- Misses        342      418      +76     
- Partials        0      269     +269     

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[ognevny]

@justsmth instead of clang you should install cc package. it will download proper compilers

[ognevny]

I looked into an error log. the problem is that wrong target is passed to clang. I don't know which crate does the build, but for cc-rs it was fixed in 1.1.10 version: rust-lang/cc-rs#1176

obviously downloading llvm won't fix the issue. the solution is to pass proper target x86_64-pc-windows-gnu

[ognevny]

we currently dropping support for 32-bit environments. there are no 32-bit packages with aws-lc, so feel free to net test mingw32

[justsmth]

🎉 First success: https://github.com/aws/aws-lc-rs/actions/runs/14795425060/job/41541411147

we currently dropping support for 32-bit environments. there are no 32-bit packages with aws-lc, so feel free to net test mingw32

Ok, I'll remove that target. Thanks!

[ognevny]

small thing to fix

warning: Compiler family detection failed due to error: ToolNotFound: failed to find tool "D:\\a\\_temp\\msys64\\clang64\\bin\\g++.exe": The system cannot find the file specified. (os error 2) (see https://docs.rs/cc/latest/cc/#compile-time-requirements for help)

this can be workarounded by downloading gcc-compat which is also named gcc for simplicity. but if it is just a warning and actual compiler family is detected then there is nothing to do

[ognevny]

the issue above is not reproducible in MSYS2 CI by the way. probably something related with mixed host and target (we usually do host == target build)

[ognevny]

thanks for all work on this!