[llvm] [openmp] [Offload] Provide a CMake cache file to easily build offloading (PR #115074)

[Shilei Tian via llvm-commits]

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@@ -0,0 +1,12 @@
+set(LLVM_ENABLE_PROJECTS "clang;clang-tools-extra;lld" CACHE STRING "")
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shiltian wrote:

FWIW, `compiler-rt` is also required sometimes, such as HIP.

https://github.com/llvm/llvm-project/pull/115074