Merge branch 'backport-ninja-lwyu-ar' into ninja-lwyu-ar

Tests/RunCMake/LinkWhatYouUse/C.cmake

@@ -2,3 +2,4 @@ enable_language(C)
 set(CMAKE_LINK_WHAT_YOU_USE TRUE)
 add_executable(main main.c)
 target_link_libraries(main m)
+add_library(foo STATIC foo.c)

Tests/RunCMake/LinkWhatYouUse/CXX.cmake

@@ -2,3 +2,4 @@ enable_language(CXX)
 set(CMAKE_LINK_WHAT_YOU_USE TRUE)
 add_executable(main main.cxx)
 target_link_libraries(main m)
+add_library(foo STATIC foo.cxx)

Tests/RunCMake/LinkWhatYouUse/foo.c

@@ -0,0 +1,4 @@
+int foo(void)
+{
+  return 0;
+}

Tests/RunCMake/LinkWhatYouUse/foo.cxx

@@ -0,0 +1,4 @@
+int foo()
+{
+  return 0;
+}