[clang] [compiler-rt] [llvm] Skipping host target exports during cross-compilation (PR #209922)

[Martin Storsjö via cfe-commits]

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@@ -1017,6 +1017,8 @@ if (CMAKE_BUILD_TYPE AND uppercase_CMAKE_BUILD_TYPE MATCHES "^(RELWITHDEBINFO|DE
   set(LLVM_OMIT_DAGISEL_COMMENTS OFF)
 endif()
 
+option(LLVM_OMIT_EXPORTS_FROM_CONFIG "Do not import LLVM and Clang exports. This is used in runtimes sub builds" OFF)
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mstorsjo wrote:

Does this strictly need to be listed as an `option()`, or can it just be a variable that we just happen to set? Alternatively, IIRC there's also some flag one can set to `option()` to make it not list the option in listings.

https://github.com/llvm/llvm-project/pull/209922