===== libxx

This directory contains three C++ library:

• A fragmentary C++ library that will allow to build only the simplest of C++ applications. In the deeply embedded world, that is probably all that is necessary.

  At present, only the following are supported here:

  .. code-block:: C

  void *operator new(std::size_t nbytes)

  .. code-block:: C

  void operator delete(void* ptr)

  .. code-block:: C

  void operator delete[](void *ptr)

  .. code-block:: C

  void __cxa_pure_virtual(void)

  .. code-block:: C

  int __aeabi_atexit(void* object, void (destroyer)(void), void *dso_handle)

  .. code-block:: C

  int __cxa_atexit(__cxa_exitfunc_t func, FAR void *arg, FAR void *dso_handle)

  This implementation is selected when neither of the following two options are enabled.

• LLVM "libc++" C++ library (http://libcxx.llvm.org/) This implementation is selected with CONFIG_LIBCXX=y.

• uClibc++ C++ library (http://cxx.uclibc.org/) This implementation is selected with CONFIG_UCLIBCXX=y.

operator new

This operator should take a type of size_t. But size_t has an unknown underlying type. In the nuttx sys/types.h header file, size_t is typed as uint32_t (which is determined by architecture-specific logic). But the C++ compiler may believe that size_t is of a different type resulting in compilation errors in the operator. Using the underlying integer type instead of size_t seems to resolve the compilation issues. Need to REVISIT this.

Once some C++ compilers, this will cause an error::

Problem:     "'operator new' takes size_t ('...') as first parameter"
Workaround:  Add -fpermissive to the compilation flags