diff --git a/Tests/RunCMake/include_directories/BinaryDirectoryInInterface.cmake b/Tests/RunCMake/include_directories/BinaryDirectoryInInterface.cmake
index 875454029..67ee7de84 100644
--- a/Tests/RunCMake/include_directories/BinaryDirectoryInInterface.cmake
+++ b/Tests/RunCMake/include_directories/BinaryDirectoryInInterface.cmake
@@ -1,5 +1,5 @@
 
-project(BinaryDirectoryInInterface)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 target_include_directories(testTarget INTERFACE "${CMAKE_CURRENT_BINARY_DIR}/foo")
diff --git a/Tests/RunCMake/include_directories/CMakeLists.txt b/Tests/RunCMake/include_directories/CMakeLists.txt
index 96a785a2b..5cd4825e6 100644
--- a/Tests/RunCMake/include_directories/CMakeLists.txt
+++ b/Tests/RunCMake/include_directories/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.0)
-project(${RunCMake_TEST} CXX)
+project(${RunCMake_TEST} NONE)
 if(NOT TEST_FILE)
   set(TEST_FILE ${RunCMake_TEST}.cmake)
 endif()
diff --git a/Tests/RunCMake/include_directories/DebugIncludes.cmake b/Tests/RunCMake/include_directories/DebugIncludes.cmake
index bbc9e4602..10a4c5020 100644
--- a/Tests/RunCMake/include_directories/DebugIncludes.cmake
+++ b/Tests/RunCMake/include_directories/DebugIncludes.cmake
@@ -1,5 +1,5 @@
 
-project(DebugIncludes)
+enable_language(CXX)
 
 set(CMAKE_DEBUG_TARGET_PROPERTIES INCLUDE_DIRECTORIES)
 
diff --git a/Tests/RunCMake/include_directories/DirInInstallPrefix.cmake b/Tests/RunCMake/include_directories/DirInInstallPrefix.cmake
index d6f08bd10..fab771718 100644
--- a/Tests/RunCMake/include_directories/DirInInstallPrefix.cmake
+++ b/Tests/RunCMake/include_directories/DirInInstallPrefix.cmake
@@ -1,4 +1,4 @@
-
+enable_language(CXX)
 add_library(testTarget empty.cpp)
 target_include_directories(testTarget INTERFACE "${CMAKE_INSTALL_PREFIX}/dir")
 
diff --git a/Tests/RunCMake/include_directories/ImportedTarget.cmake b/Tests/RunCMake/include_directories/ImportedTarget.cmake
index e1a20b130..f752f98e9 100644
--- a/Tests/RunCMake/include_directories/ImportedTarget.cmake
+++ b/Tests/RunCMake/include_directories/ImportedTarget.cmake
@@ -1,5 +1,5 @@
 
-project(ImportedTarget)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 
diff --git a/Tests/RunCMake/include_directories/InstallPrefixInInterface.cmake b/Tests/RunCMake/include_directories/InstallPrefixInInterface.cmake
index 0f08e5884..8d777f53c 100644
--- a/Tests/RunCMake/include_directories/InstallPrefixInInterface.cmake
+++ b/Tests/RunCMake/include_directories/InstallPrefixInInterface.cmake
@@ -1,5 +1,5 @@
 
-project(InstallPrefixInInterface)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 target_include_directories(testTarget INTERFACE "${CMAKE_INSTALL_PREFIX}/foo")
diff --git a/Tests/RunCMake/include_directories/RelativePathInGenex.cmake b/Tests/RunCMake/include_directories/RelativePathInGenex.cmake
index f72cf3adb..070a381d2 100644
--- a/Tests/RunCMake/include_directories/RelativePathInGenex.cmake
+++ b/Tests/RunCMake/include_directories/RelativePathInGenex.cmake
@@ -1,5 +1,5 @@
 
-project(RelativePathInInterface)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 set_property(TARGET testTarget PROPERTY INTERFACE_INCLUDE_DIRECTORIES "$<1:foo>")
diff --git a/Tests/RunCMake/include_directories/RelativePathInInterface.cmake b/Tests/RunCMake/include_directories/RelativePathInInterface.cmake
index f2ce54ae2..4c4727d42 100644
--- a/Tests/RunCMake/include_directories/RelativePathInInterface.cmake
+++ b/Tests/RunCMake/include_directories/RelativePathInInterface.cmake
@@ -1,5 +1,5 @@
 
-project(RelativePathInInterface)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 set_property(TARGET testTarget PROPERTY INTERFACE_INCLUDE_DIRECTORIES "foo")
diff --git a/Tests/RunCMake/include_directories/SourceDirectoryInInterface.cmake b/Tests/RunCMake/include_directories/SourceDirectoryInInterface.cmake
index c9a9c457b..f814a3ca3 100644
--- a/Tests/RunCMake/include_directories/SourceDirectoryInInterface.cmake
+++ b/Tests/RunCMake/include_directories/SourceDirectoryInInterface.cmake
@@ -1,5 +1,5 @@
 
-project(SourceDirectoryInInterface)
+enable_language(CXX)
 
 add_library(testTarget "${CMAKE_CURRENT_SOURCE_DIR}/empty.cpp")
 target_include_directories(testTarget INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/foo")
diff --git a/Tests/RunCMake/include_directories/export-NOWARN.cmake b/Tests/RunCMake/include_directories/export-NOWARN.cmake
index 307ce5a65..50720a0c8 100644
--- a/Tests/RunCMake/include_directories/export-NOWARN.cmake
+++ b/Tests/RunCMake/include_directories/export-NOWARN.cmake
@@ -1,4 +1,4 @@
-
+enable_language(CXX)
 add_library(foo empty.cpp)
 set_property(TARGET foo APPEND PROPERTY INTERFACE_INCLUDE_DIRECTORIES $<0:>/include/subdir)
 set_property(TARGET foo APPEND PROPERTY INTERFACE_INCLUDE_DIRECTORIES $<INSTALL_PREFIX>/include/subdir)
diff --git a/Tests/RunCMake/include_directories/incomplete-genex.cmake b/Tests/RunCMake/include_directories/incomplete-genex.cmake
index b6900a464..976695a64 100644
--- a/Tests/RunCMake/include_directories/incomplete-genex.cmake
+++ b/Tests/RunCMake/include_directories/incomplete-genex.cmake
@@ -1,4 +1,4 @@
-project(incomplete-genex)
+enable_language(CXX)
 
 cmake_policy(SET CMP0022 NEW)
 cmake_policy(SET CMP0023 NEW)