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Robin Gareus 520dcf8cdf rework lua-bridge C++ variable references 
Since lua functions are closures, C++ methods that pass arguments by
reference cannot be used directly. The previous approach (boost::ref)
failed with clang. Assume the following:

  void foo (float&) { }
  static inline float& bar () {
    boost::reference_wrapper<float> r (42);
    return r.get ();
  }

  foo ( bar () );

With gcc, "r" goes out of scope after foo's arguments are processed
and all is well.
But with clang,  "r" already leave scope when *inlined* bar() returns.

Solution: allocate some user-data on the lua-stack to hold the reference.
There is no reference to this user-data so lua will eventually
garbage collect it.

(theoretically, creating the table which holds the return-values
could trigger an emergency garbage collection when memory is low and
free the reference just while they're being pushed to the table, then
gain FuncArgs<Params> already dereferenced them all as variable on the
C stack -- probably again compiler specific)
2016-07-18 23:52:40 +02:00
..
detail rework lua-bridge C++ variable references 2016-07-18 23:52:40 +02:00
LuaBridge.h rework lua-bridge C++ variable references 2016-07-18 23:52:40 +02:00
README

README 

https://github.com/vinniefalco/LuaBridge  --  1.0.2-111-g04b47d7

LuaBridge is published under the terms of the MIT License.

  Copyright 2012, Vinnie Falco (<vinnie.falco@gmail.com>)
	Copyright 2008, Nigel Atkinson
	Copyright 2007, Nathan Reed

	Portions from The Loki Library:
	Copyright (C) 2001 by Andrei Alexandrescu

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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SOFTWARE.