Languages: Add support for Objective-C++

Add entries in Modules and Modules/Platform to support
Objective-C++ compiler determination and identification.
Add Modules to check Objective-C++ compiler flags, source
compilations, program checks, etc...

Use OBJCXX as the designator of the language, eg:

project(foo OBJCXX)

Add various tests for Objective-C++ language features.  Add
tests to preserve C++ handling of .M and .mm files when
Objective-C++ is not a configured language.

Co-authored-by: Cristian Adam <cristian.adam@gmail.com>

1 files changed, 46 insertions, 20 deletions

diff --git a/Tests/TryCompile/CMakeLists.txt b/Tests/TryCompile/CMakeLists.txt
index 8fd8090..498e556 100644
--- a/Tests/TryCompile/CMakeLists.txt
+++ b/Tests/TryCompile/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required (VERSION 2.6)
-project(TryCompile OBJC C CXX)
+project(TryCompile)
 
 macro(TEST_ASSERT value msg)
   if (NOT ${value})
@@ -315,31 +315,57 @@ endif()
 
 #########################################################################
 #
-# Test that the CHECK_OBJCC_SOURCE_COMPILES, CHECK_OBJC_SOURCE_RUNS
-# macros work.
+# Test that the CHECK_OBJCC_SOURCE_COMPILES, CHECK_OBJCXX_SOURCE_COMPILES
+# CHECK_OBJC_SOURCE_RUNS and CHECK_OBJCXX_SOURCE_RUNS macros work
 
-include(CheckOBJCSourceCompiles)
-include(CheckOBJCSourceRuns)
+if (APPLE)
+    enable_language(OBJC)
+    enable_language(OBJCXX)
 
-CHECK_OBJC_SOURCE_COMPILES("I don't build in Objective-C" OBJC_BUILD_SHOULD_FAIL)
-CHECK_OBJC_SOURCE_COMPILES("int main() { return 0; }" SIMPLE_OBJC_BUILD_SHOULD_WORK)
+    include(CheckOBJCSourceCompiles)
+    include(CheckOBJCXXSourceCompiles)
+    include(CheckOBJCSourceRuns)
+    include(CheckOBJCXXSourceRuns)
 
-TEST_FAIL(OBJC_BUILD_SHOULD_FAIL "CHECK_OBJC_SOURCE_COMPILES() succeeded, but should have failed")
-TEST_ASSERT(SIMPLE_OBJC_BUILD_SHOULD_WORK "CHECK_OBJC_SOURCE_COMPILES() failed, but should have succeeded")
+    CHECK_OBJC_SOURCE_COMPILES("I don't build in Objective-C" OBJC_BUILD_SHOULD_FAIL)
+    CHECK_OBJC_SOURCE_COMPILES("int main() { return 0; }" SIMPLE_OBJC_BUILD_SHOULD_WORK)
 
-set(CMAKE_REQUIRED_LIBRARIES "-framework Foundation")
+    TEST_FAIL(OBJC_BUILD_SHOULD_FAIL "CHECK_OBJC_SOURCE_COMPILES() succeeded, but should have failed")
+    TEST_ASSERT(SIMPLE_OBJC_BUILD_SHOULD_WORK "CHECK_OBJC_SOURCE_COMPILES() failed, but should have succeeded")
 
-CHECK_OBJC_SOURCE_COMPILES("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 0;\n}\n" OBJC_BUILD_SHOULD_WORK)
-CHECK_OBJC_SOURCE_RUNS("int main() { return 2; }" SIMPLE_OBJC_RUN_SHOULD_FAIL)
-CHECK_OBJC_SOURCE_RUNS("int main() { return 0; }" SIMPLE_OBJC_RUN_SHOULD_WORK)
-CHECK_OBJC_SOURCE_RUNS("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 2;\n}\n" OBJC_RUN_SHOULD_FAIL)
-CHECK_OBJC_SOURCE_RUNS("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 0;\n}\n" OBJC_RUN_SHOULD_WORK)
+    set(CMAKE_REQUIRED_LIBRARIES "-framework Foundation")
 
-TEST_ASSERT(OBJC_BUILD_SHOULD_WORK "CHECK_OBJC_SOURCE_COMPILES() failed, but should have succeeded")
-TEST_FAIL(SIMPLE_OBJC_RUN_SHOULD_FAIL "CHECK_OBJC_SOURC_RUNS() succeeds, but should have failed")
-TEST_ASSERT(SIMPLE_OBJC_RUN_SHOULD_WORK "CHECK_OBJC_SOURCE_RUNS() failed, but should have succeeded")
-TEST_FAIL(OBJC_RUN_SHOULD_FAIL "CHECK_OBJC_SOURCE_RUNS() succeeds, but should have failed")
-TEST_ASSERT(OBJC_RUN_SHOULD_WORK "CHECK_OBJC_SOURCE_RUNS() failed, but should have succeeded")
+    CHECK_OBJC_SOURCE_COMPILES("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 0;\n}\n" OBJC_BUILD_SHOULD_WORK)
+    CHECK_OBJC_SOURCE_RUNS("int main() { return 2; }" SIMPLE_OBJC_RUN_SHOULD_FAIL)
+    CHECK_OBJC_SOURCE_RUNS("int main() { return 0; }" SIMPLE_OBJC_RUN_SHOULD_WORK)
+    CHECK_OBJC_SOURCE_RUNS("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 2;\n}\n" OBJC_RUN_SHOULD_FAIL)
+    CHECK_OBJC_SOURCE_RUNS("#import <Foundation/Foundation.h>\nint main()\n{\nNSObject *foo;\nreturn 0;\n}\n" OBJC_RUN_SHOULD_WORK)
+
+    TEST_ASSERT(OBJC_BUILD_SHOULD_WORK "CHECK_OBJC_SOURCE_COMPILES() failed, but should have succeeded")
+    TEST_FAIL(SIMPLE_OBJC_RUN_SHOULD_FAIL "CHECK_OBJC_SOURC_RUNS() succeeds, but should have failed")
+    TEST_ASSERT(SIMPLE_OBJC_RUN_SHOULD_WORK "CHECK_OBJC_SOURCE_RUNS() failed, but should have succeeded")
+    TEST_FAIL(OBJC_RUN_SHOULD_FAIL "CHECK_OBJC_SOURCE_RUNS() succeeds, but should have failed")
+    TEST_ASSERT(OBJC_RUN_SHOULD_WORK "CHECK_OBJC_SOURCE_RUNS() failed, but should have succeeded")
+
+
+    CHECK_OBJCXX_SOURCE_COMPILES("I don't build in Objective-C++" OBJCXX_BUILD_SHOULD_FAIL)
+    CHECK_OBJCXX_SOURCE_COMPILES("int main() { return 0; }" SIMPLE_OBJCXX_BUILD_SHOULD_WORK)
+
+    TEST_FAIL(OBJCXX_BUILD_SHOULD_FAIL "CHECK_OBJCXX_SOURCE_COMPILES() succeeded, but should have failed")
+    TEST_ASSERT(SIMPLE_OBJCXX_BUILD_SHOULD_WORK "CHECK_OBJCXX_SOURCE_COMPILES() failed, but should have succeeded")
+
+    CHECK_OBJCXX_SOURCE_COMPILES("#import <Foundation/Foundation.h>\n#include <iostream>\nint main()\n{\nNSObject *foo;\nstd::cout << \"Hello\" << std::endl;\nreturn 0;\n}\n" OBJCXX_BUILD_SHOULD_WORK)
+    CHECK_OBJCXX_SOURCE_RUNS("int main() { return 2; }" SIMPLE_OBJCXX_RUN_SHOULD_FAIL)
+    CHECK_OBJCXX_SOURCE_RUNS("int main() { return 0; }" SIMPLE_OBJCXX_RUN_SHOULD_WORK)
+    CHECK_OBJCXX_SOURCE_RUNS("#import <Foundation/Foundation.h>\n#include <vector>\nint main()\n{\nNSObject *foo;\nstd::vector<int> bar;\nreturn 2;\n}\n" OBJCXX_RUN_SHOULD_FAIL)
+    CHECK_OBJCXX_SOURCE_RUNS("#import <Foundation/Foundation.h>\n#include <vector>\nint main()\n{\nNSObject *foo;\nstd::vector<int> bar;\nreturn 0;\n}\n" OBJCXX_RUN_SHOULD_WORK)
+
+    TEST_ASSERT(OBJCXX_BUILD_SHOULD_WORK "CHECK_OBJCXX_SOURCE_COMPILES() failed, but should have succeeded")
+    TEST_FAIL(SIMPLE_OBJCXX_RUN_SHOULD_FAIL "CHECK_OBJCXX_SOURC_RUNS() succeeds, but should have failed")
+    TEST_ASSERT(SIMPLE_OBJCXX_RUN_SHOULD_WORK "CHECK_OBJCXX_SOURCE_RUNS() failed, but should have succeeded")
+    TEST_FAIL(OBJCXX_RUN_SHOULD_FAIL "CHECK_OBJCXX_SOURCE_RUNS() succeeds, but should have failed")
+    TEST_ASSERT(OBJCXX_RUN_SHOULD_WORK "CHECK_OBJCXX_SOURCE_RUNS() failed, but should have succeeded")
+endif()
 
 #######################################################################
 #