xref: /third_party/mesa3d/include/no_extern_c.h

/**************************************************************************
 *
 * Copyright 2014 VMware, Inc.
 * All Rights Reserved.
 *
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 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
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 * 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.
 *
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 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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/*
 * Including system's headers inside `extern "C" { ... }` is not safe, as system
 * headers may have C++ code in them, and C++ code inside extern "C"
 * leads to syntactically incorrect code.
 *
 * This is because putting code inside extern "C" won't make __cplusplus define
 * go away, that is, the system header being included thinks is free to use C++
 * as it sees fits.
 *
 * Including non-system headers inside extern "C"  is not safe either, because
 * non-system headers end up including system headers, hence fall in the above
 * case too.
 *
 * Conclusion, includes inside extern "C" is simply not portable.
 *
 *
 * This header helps surface these issues.
 */

#ifdef __cplusplus
template<class T> class _IncludeInsideExternCNotPortable;
#endif