base/compiler_specific.h

// Copyright 2008, Google Inc.
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are
// met:
//
//    * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
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// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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#ifndef BASE_COMPILER_SPECIFIC_H_
#define BASE_COMPILER_SPECIFIC_H_

#include "build/build_config.h"

#if defined(COMPILER_MSVC)

// Macros for suppressing and disabling warnings on MSVC.
//
// Warning numbers are enumerated at:
// http://msdn.microsoft.com/en-us/library/8x5x43k7(VS.80).aspx
//
// The warning pragma:
// http://msdn.microsoft.com/en-us/library/2c8f766e(VS.80).aspx
//
// Using __pragma instead of #pragma inside macros:
// http://msdn.microsoft.com/en-us/library/d9x1s805.aspx

// MSVC_SUPPRESS_WARNING disables warning |n| for the remainder of the line and
// for the next line of the source file.
#define MSVC_SUPPRESS_WARNING(n) __pragma(warning(suppress:n))

// MSVC_PUSH_DISABLE_WARNING pushes |n| onto a stack of warnings to be disabled.
// The warning remains disabled until popped by MSVC_POP_WARNING.
#define MSVC_PUSH_DISABLE_WARNING(n) __pragma(warning(push)) \
                                     __pragma(warning(disable:n))
#define MSVC_POP_WARNING() __pragma(warning(pop))

// Allows |this| to be passed as an argument in constructor initializer lists.
// This uses push/pop instead of the seemingly simpler suppress feature to avoid
// having the warning be disabled for more than just |code|.
//
// Example usage:
// Foo::Foo() : x(NULL), ALLOW_THIS_IN_INITIALIZER_LIST(y(this)), z(3) {}
//
// Compiler warning C4355: 'this': used in base member initializer list:
// http://msdn.microsoft.com/en-us/library/3c594ae3(VS.80).aspx
#define ALLOW_THIS_IN_INITIALIZER_LIST(code) MSVC_PUSH_DISABLE_WARNING(4355) \
                                             code \
                                             MSVC_POP_WARNING()

#else  // COMPILER_MSVC

#define MSVC_SUPPRESS_WARNING(n)
#define MSVC_PUSH_DISABLE_WARNING(n)
#define MSVC_POP_WARNING()
#define ALLOW_THIS_IN_INITIALIZER_LIST(code) code

#endif  // COMPILER_MSVC

#endif  // BASE_COMPILER_SPECIFIC_H_