[clang] [runtimes] Fix parsing of LIB{CXX, CXXABI, UNWIND}_TEST_PARAMS (PR #67691)

[Vladimir Vereschaka via cfe-commits]

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@@ -151,6 +151,10 @@ set(RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_LIBCXX_ENABLE_NEW_DELETE_DEFINITIONS
 
 find_package(Python3 COMPONENTS Interpreter)
 
+set(RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_LIBUNWIND_TEST_PARAMS "${RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_TEST_PARAMS}" CACHE INTERNAL "")
+set(RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_LIBCXXABI_TEST_PARAMS "${RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_TEST_PARAMS}" CACHE INTERNAL "")
+set(RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_LIBCXX_TEST_PARAMS "${RUNTIMES_${TOOLCHAIN_TARGET_TRIPLE}_TEST_PARAMS}" CACHE INTERNAL "")
+
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vvereschaka wrote:

It is not working. This will store the empty variables in the cache file. If you check your local `CMakeCache.txt` for these variables you'll find them empty. You need to cache them with the values at the end of preparation (please check my original diff file).

https://github.com/llvm/llvm-project/pull/67691