[CMake] Use correct visibility for linked libraries in CMake

When linking library dependencies, we shouldn't need to export linked
libraries to dependents. We should be explicit about this in
target_link_libraries, otherwise other targets that depend on these such
as sanitizers get repeated (and possibly even conflicting) dependencies.

Differential Revision: https://reviews.llvm.org/D57456

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@352688 91177308-0d34-0410-b5e6-96231b3b80d8

benchmarks/CMakeLists.txt

@@ -137,6 +137,7 @@ function(add_benchmark_test name source_file)
   add_executable(${libcxx_target} EXCLUDE_FROM_ALL ${source_file})
   add_dependencies(${libcxx_target} cxx cxx-headers google-benchmark-libcxx)
   add_dependencies(cxx-benchmarks ${libcxx_target})
+  target_link_libraries(${libcxx_target} ${LIBCXX_LIBRARIES})
   if (LIBCXX_ENABLE_SHARED)
     target_link_libraries(${libcxx_target} cxx_shared)
   else()

lib/CMakeLists.txt

@@ -241,7 +241,7 @@ if (LIBCXX_ENABLE_SHARED)
   if(COMMAND llvm_setup_rpath)
     llvm_setup_rpath(cxx_shared)
   endif()
-  target_link_libraries(cxx_shared ${LIBCXX_LIBRARIES})
+  target_link_libraries(cxx_shared PRIVATE ${LIBCXX_LIBRARIES})
   set_target_properties(cxx_shared
     PROPERTIES
       LINK_FLAGS    "${LIBCXX_LINK_FLAGS}"
@@ -265,7 +265,7 @@ endif()
 # Build the static library.
 if (LIBCXX_ENABLE_STATIC)
   add_library(cxx_static STATIC ${cxx_static_sources})
-  target_link_libraries(cxx_static ${LIBCXX_LIBRARIES})
+  target_link_libraries(cxx_static PRIVATE ${LIBCXX_LIBRARIES})
   set(CMAKE_STATIC_LIBRARY_PREFIX "lib")
   set_target_properties(cxx_static
     PROPERTIES
@@ -461,3 +461,8 @@ if (NOT CMAKE_CONFIGURATION_TYPES AND (LIBCXX_INSTALL_LIBRARY OR
                       -P "${LIBCXX_BINARY_DIR}/cmake_install.cmake")
     add_custom_target(install-libcxx DEPENDS install-cxx)
 endif()
+
+# TODO: This is needed by cxx-benchmarks but this variable isn't
+# available outside of the scope of this file so we need to export
+# it. This is not necessarily the cleanest solution.
+set(LIBCXX_LIBRARIES ${LIBCXX_LIBRARIES} PARENT_SCOPE)