[libcxx] [llvm] [clang] [libunwind] [clang-tools-extra] [libc++] Allow running the test suite with optimizations (PR #68753)

[Mark de Wever via cfe-commits]

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@@ -0,0 +1,4 @@
+set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
+set(LIBCXX_TEST_PARAMS "optimization=speed" CACHE STRING "")
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mordante wrote:

Since it's possible to optimized for size too, I'd like "speed" in the name of the cache.

https://github.com/llvm/llvm-project/pull/68753