[llvm] [clang] [CMake][PGO] Add option for using an external project to generate profile data (PR #78879)

[Amir Ayupov via cfe-commits]

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@@ -2,7 +2,7 @@ set(CMAKE_BUILD_TYPE RELEASE CACHE STRING "")
 set(CLANG_ENABLE_BOOTSTRAP ON CACHE BOOL "")
 
 set(LLVM_ENABLE_PROJECTS "clang;lld" CACHE STRING "")
-set(LLVM_ENABLE_RUNTIMES "compiler-rt;libcxx;libcxxabi" CACHE STRING "")
+set(LLVM_ENABLE_RUNTIMES "compiler-rt;libcxx;libcxxabi;libunwind" CACHE STRING "")
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aaupov wrote:

Makes sense to avoid touching to prevent conflicts with https://github.com/llvm/llvm-project/pull/78869.

https://github.com/llvm/llvm-project/pull/78879