Merge branch 'maint' * maint: tests: avoid spurious failure on missing Obj C/C++ compiler objc, objc++: test support for compilation flags objc, objc++: add stress test objc, objc++: test automatic dependency tracking objc: reorganize basic tests objc++, objc: add first semantic tests objc++: add first basic test news: announce initial support for Objective C++ objc++: test support for '.mm' suffix in _SOURCES entries objc++: add documentation objc++: initial support for Objective C++