[clang] [compiler-rt] [llvm] Get the linker version and pass the it to compiler-rt tests on Darwin. (PR #86220)

[Julian Lettner via cfe-commits]

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@@ -51,6 +51,7 @@ set_default("expensive_checks", @LLVM_ENABLE_EXPENSIVE_CHECKS_PYBOOL@)
 set_default("test_standalone_build_libs", @COMPILER_RT_TEST_STANDALONE_BUILD_LIBS_PYBOOL@)
 set_default("has_compiler_rt_libatomic", @COMPILER_RT_BUILD_STANDALONE_LIBATOMIC_PYBOOL@)
 set_default("aarch64_sme", @COMPILER_RT_HAS_AARCH64_SME_PYBOOL@)
+set_default("host_link_version", "@HOST_LINK_VERSION@")
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yln wrote:

- [ ]  Many of the other vars here have a `COMPILER_RT` prefix.  Should we do the same or does it imply some additional semantics ("user option" in CMAKE script)?
- [ ] `set_default("darwin_linker_version", "@COMPILER_RT_DARWIN_LINKER_VERSION@")`

https://github.com/llvm/llvm-project/pull/86220