diff --git a/clang/tools/c-index-test/CMakeLists.txt b/clang/tools/c-index-test/CMakeLists.txt
index abf3cc4400c3..4c724659f6f6 100644
--- a/clang/tools/c-index-test/CMakeLists.txt
+++ b/clang/tools/c-index-test/CMakeLists.txt
@@ -18,3 +18,8 @@ set( LLVM_LINK_COMPONENTS
 add_clang_executable(c-index-test
   c-index-test.c
   )
+
+set_target_properties(c-index-test
+  PROPERTIES
+  LINKER_LANGUAGE CXX)
+