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+libxx/README.txt
+^^^^^^^^^^^^^^^^
+
+This directory contains 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.  If you
+have a need for more extensive C++ support, the following libraries
+are recommended:
+
+ - libstdc++  (part of GCC)
+ - STLport    http://www.stlport.org/ 
+ - uClibc++   http://cxx.uclibc.org/
+ - uSTL       http://ustl.sourceforge.net/
+
+At present, only the following are supported here:
+
+ - void *operator new(std::size_t nbytes);
+ - void operator delete(void* ptr);
+ - void operator delete[](void *ptr);
+ - void __cxa_pure_virtual(void);
+ - int __aeabi_atexit(void* object, void (*destroyer)(void*), void *dso_handle);
+ 
+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