[libunwind] [libunwind] Make sure libunwind test dependencies are installed before running tests (PR #171474)

[Louis Dionne via cfe-commits]

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@@ -9,6 +9,26 @@ macro(pythonize_bool var)
 endmacro()
 
 set(LIBUNWIND_TESTING_INSTALL_PREFIX "${LIBUNWIND_BINARY_DIR}/test-suite-install")
+add_custom_target(libunwind-install-cxx-for-testing
+                    DEPENDS cxx-headers
+                            cxx
+                            cxx_experimental
+                            cxx-modules
+                    COMMAND ${CMAKE_COMMAND} -E make_directory "${LIBUNWIND_TESTING_INSTALL_PREFIX}"
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ldionne wrote:

That's a good observation, thanks! And in fact I think I can refactor this a bunch further.

https://github.com/llvm/llvm-project/pull/171474