[llvm] Reapply "[CI] Migrate to runtimes build" (#143612) (PR #144033)

[via llvm-commits]

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@@ -122,10 +126,10 @@
     "polly": "check-polly",
 }
 
-RUNTIMES = {"libcxx", "libcxxabi", "libunwind"}
+RUNTIMES = {"libcxx", "libcxxabi", "libunwind", "compiler-rt", "libc"}
 
 
-def _add_dependencies(projects: Set[str]) -> Set[str]:
+def _add_dependencies(projects: Set[str], runtimes: Set[str]) -> Set[str]:
     projects_with_dependents = set(projects)
     current_projects_count = 0
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cmtice wrote:

I don't see where current_projects_count ever gets updated; what's to prevent this from looping forever?

https://github.com/llvm/llvm-project/pull/144033