Merge commit '4e3fc39b038f' from apple/stable/20200714 into swift/release/5.4

Author: git apple-llvm automerger

clang/CMakeLists.txt

@@ -508,7 +508,7 @@ set(CLANG_EXECUTABLE_VERSION
     "${CLANG_VERSION_MAJOR}" CACHE STRING
     "Major version number that will be appended to the clang executable name")
 set(LIBCLANG_LIBRARY_VERSION
-    "${CLANG_VERSION_MAJOR}" CACHE STRING
+    "${CLANG_VERSION_MAJOR}.${CLANG_VERSION_MINOR}" CACHE STRING
     "Major version number that will be appended to the libclang library")
 mark_as_advanced(CLANG_EXECUTABLE_VERSION LIBCLANG_LIBRARY_VERSION)
 

clang/tools/clang-shlib/CMakeLists.txt

@@ -48,3 +48,8 @@ add_clang_library(clang-cpp
                   ${_OBJECTS}
                   LINK_LIBS
                   ${_DEPS})
+
+    set_target_properties(clang-cpp
+      PROPERTIES
+      VERSION ${LIBCLANG_LIBRARY_VERSION}
+      SOVERSION ${LIBCLANG_LIBRARY_VERSION})

clang/tools/libclang/CMakeLists.txt

@@ -159,6 +159,7 @@ if(ENABLE_SHARED)
   else()
     set_target_properties(libclang
       PROPERTIES
+      SOVERSION ${LIBCLANG_LIBRARY_VERSION}
       VERSION ${LIBCLANG_LIBRARY_VERSION}
       DEFINE_SYMBOL _CINDEX_LIB_)
     # FIXME: _CINDEX_LIB_ affects dllexport/dllimport on Win32.