[CMake] Introduce cmake_policy(CMP0022) for target_link_libraries(INTERFACE|PRIVATE).

For now, use both keywords, INTERFACE and PRIVATE via the variable,
  - ${cmake_2_8_12_INTERFACE}
  - ${cmake_2_8_12_PRIVATE}

They could be cleaned up when we introduce 2.8.12.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202239 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/CMakeLists.txt b/CMakeLists.txt
index aa2fe14fe239f8417aea874ebe1b9a7c31e45b10..2ce214aabfcd25744b5396ea14103bf16a7c3194 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,21 @@
 # See docs/CMake.html for instructions about how to build LLVM with CMake.
 
 cmake_minimum_required(VERSION 2.8.8)
+
+# FIXME: It may be removed when we use 2.8.12.
+if(CMAKE_VERSION VERSION_LESS 2.8.12)
+  # Invalidate a couple of keywords.
+  set(cmake_2_8_12_INTERFACE)
+  set(cmake_2_8_12_PRIVATE)
+else()
+  # Use ${cmake_2_8_12_KEYWORD} intead of KEYWORD in target_link_libraries().
+  set(cmake_2_8_12_INTERFACE INTERFACE)
+  set(cmake_2_8_12_PRIVATE PRIVATE)
+  if(POLICY CMP0022)
+    cmake_policy(SET CMP0022 NEW) # automatic when 2.8.12 is required
+  endif()
+endif()
+
 project(LLVM)
 
 # Add path for custom modules