[clang] [llvm] [cmake] Add config for riscv(32|64)-unknown-elf (PR #176353)

[Ramkumar Ramachandra via cfe-commits]

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@@ -899,6 +899,9 @@ else()
   option(LLVM_BUILD_LLVM_C_DYLIB "Build libllvm-c re-export library (Darwin only)" OFF)
 endif()
 
+option(LLVM_CONFIG_NO_EXPORTS "Suppress exports in CMake package" OFF)
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artagnon wrote:

As the PR description says, we wouldn't be able to use BaremetalRISCV.cmake without this option, as CMake errors out on add_library SHARED and MODULE in LLVMExports and LLVMBuildTreeOnlyExports?

https://github.com/llvm/llvm-project/pull/176353