1// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef BASE_COMPILER_SPECIFIC_H_ 6#define BASE_COMPILER_SPECIFIC_H_ 7#pragma once 8 9#include "build/build_config.h" 10 11#if defined(COMPILER_MSVC) 12 13// Macros for suppressing and disabling warnings on MSVC. 14// 15// Warning numbers are enumerated at: 16// http://msdn.microsoft.com/en-us/library/8x5x43k7(VS.80).aspx 17// 18// The warning pragma: 19// http://msdn.microsoft.com/en-us/library/2c8f766e(VS.80).aspx 20// 21// Using __pragma instead of #pragma inside macros: 22// http://msdn.microsoft.com/en-us/library/d9x1s805.aspx 23 24// MSVC_SUPPRESS_WARNING disables warning |n| for the remainder of the line and 25// for the next line of the source file. 26#define MSVC_SUPPRESS_WARNING(n) __pragma(warning(suppress:n)) 27 28// MSVC_PUSH_DISABLE_WARNING pushes |n| onto a stack of warnings to be disabled. 29// The warning remains disabled until popped by MSVC_POP_WARNING. 30#define MSVC_PUSH_DISABLE_WARNING(n) __pragma(warning(push)) \ 31 __pragma(warning(disable:n)) 32 33// MSVC_PUSH_WARNING_LEVEL pushes |n| as the global warning level. The level 34// remains in effect until popped by MSVC_POP_WARNING(). Use 0 to disable all 35// warnings. 36#define MSVC_PUSH_WARNING_LEVEL(n) __pragma(warning(push, n)) 37 38// Pop effects of innermost MSVC_PUSH_* macro. 39#define MSVC_POP_WARNING() __pragma(warning(pop)) 40 41#define MSVC_DISABLE_OPTIMIZE() __pragma(optimize("", off)) 42#define MSVC_ENABLE_OPTIMIZE() __pragma(optimize("", on)) 43 44// Allows |this| to be passed as an argument in constructor initializer lists. 45// This uses push/pop instead of the seemingly simpler suppress feature to avoid 46// having the warning be disabled for more than just |code|. 47// 48// Example usage: 49// Foo::Foo() : x(NULL), ALLOW_THIS_IN_INITIALIZER_LIST(y(this)), z(3) {} 50// 51// Compiler warning C4355: 'this': used in base member initializer list: 52// http://msdn.microsoft.com/en-us/library/3c594ae3(VS.80).aspx 53#define ALLOW_THIS_IN_INITIALIZER_LIST(code) MSVC_PUSH_DISABLE_WARNING(4355) \ 54 code \ 55 MSVC_POP_WARNING() 56 57#else // Not MSVC 58 59#define MSVC_SUPPRESS_WARNING(n) 60#define MSVC_PUSH_DISABLE_WARNING(n) 61#define MSVC_PUSH_WARNING_LEVEL(n) 62#define MSVC_POP_WARNING() 63#define MSVC_DISABLE_OPTIMIZE() 64#define MSVC_ENABLE_OPTIMIZE() 65#define ALLOW_THIS_IN_INITIALIZER_LIST(code) code 66 67#endif // COMPILER_MSVC 68 69 70// Annotate a variable indicating it's ok if the variable is not used. 71// (Typically used to silence a compiler warning when the assignment 72// is important for some other reason.) 73// Use like: 74// int x ALLOW_UNUSED = ...; 75#if defined(COMPILER_GCC) 76#define ALLOW_UNUSED __attribute__((unused)) 77#define NOINLINE __attribute__((noinline)) 78#else 79#define ALLOW_UNUSED 80#define NOINLINE 81#endif 82 83// Annotate a virtual method indicating it must be overriding a virtual 84// method in the parent class. 85// Use like: 86// virtual void foo() OVERRIDE; 87#if defined(COMPILER_MSVC) 88#define OVERRIDE override 89#elif defined(__clang__) 90#define OVERRIDE override 91#else 92#define OVERRIDE 93#endif 94 95// Annotate a function indicating the caller must examine the return value. 96// Use like: 97// int foo() WARN_UNUSED_RESULT; 98#if defined(COMPILER_GCC) 99#define WARN_UNUSED_RESULT __attribute__((warn_unused_result)) 100#else 101#define WARN_UNUSED_RESULT 102#endif 103 104// Tell the compiler a function is using a printf-style format string. 105// |format_param| is the one-based index of the format string parameter; 106// |dots_param| is the one-based index of the "..." parameter. 107// For v*printf functions (which take a va_list), pass 0 for dots_param. 108// (This is undocumented but matches what the system C headers do.) 109#if defined(COMPILER_GCC) 110#define PRINTF_FORMAT(format_param, dots_param) \ 111 __attribute__((format(printf, format_param, dots_param))) 112#else 113#define PRINTF_FORMAT(format_param, dots_param) 114#endif 115 116// WPRINTF_FORMAT is the same, but for wide format strings. 117// This doesn't appear to yet be implemented in any compiler. 118// See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38308 . 119#define WPRINTF_FORMAT(format_param, dots_param) 120// If available, it would look like: 121// __attribute__((format(wprintf, format_param, dots_param))) 122 123#endif // BASE_COMPILER_SPECIFIC_H_ 124