[clang] [llvm] [clang][ci] Move libc++ testing into the main PR pipeline (PR #93318)

[Mehdi Amini via llvm-commits]

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@@ -231,6 +245,10 @@ linux_projects_to_test=$(exclude-linux $(compute-projects-to-test ${modified_pro
 linux_check_targets=$(check-targets ${linux_projects_to_test} | sort | uniq)
 linux_projects=$(add-dependencies ${linux_projects_to_test} | sort | uniq)
 
+linux_runtimes_to_test=$(compute-runtimes-to-test ${linux_projects_to_test})
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joker-eph wrote:

Sure, in theory... But that seems like a stretch to me.

I remember recently that clang folks argued to removed the flang tests when changing clang because of the likelihood of breaking Flang with clang tests.
I'm not sure the probability of a random LLVM change breaking clang in a way that would only show up with a runtime tests and no other LLVM/clang test is higher!
The ratio value / cost isn't clear to me right now.


https://github.com/llvm/llvm-project/pull/93318