1 // Copyright 2014 the V8 project 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 V8_BASE_COMPILER_SPECIFIC_H_ 6 #define V8_BASE_COMPILER_SPECIFIC_H_ 7 8 #include "include/v8config.h" 9 10 // Annotate a typedef or function indicating it's ok if it's not used. 11 // Use like: 12 // typedef Foo Bar ALLOW_UNUSED_TYPE; 13 #if V8_HAS_ATTRIBUTE_UNUSED 14 #define ALLOW_UNUSED_TYPE __attribute__((unused)) 15 #else 16 #define ALLOW_UNUSED_TYPE 17 #endif 18 19 20 // Annotate a function indicating the caller must examine the return value. 21 // Use like: 22 // int foo() WARN_UNUSED_RESULT; 23 #if V8_HAS_ATTRIBUTE_WARN_UNUSED_RESULT 24 #define WARN_UNUSED_RESULT __attribute__((warn_unused_result)) 25 #else 26 #define WARN_UNUSED_RESULT /* NOT SUPPORTED */ 27 #endif 28 29 // Tell the compiler a function is using a printf-style format string. 30 // |format_param| is the one-based index of the format string parameter; 31 // |dots_param| is the one-based index of the "..." parameter. 32 // For v*printf functions (which take a va_list), pass 0 for dots_param. 33 // (This is undocumented but matches what the system C headers do.) 34 #if defined(__GNUC__) 35 #define PRINTF_FORMAT(format_param, dots_param) \ 36 __attribute__((format(printf, format_param, dots_param))) 37 #else 38 #define PRINTF_FORMAT(format_param, dots_param) 39 #endif 40 41 // The C++ standard requires that static const members have an out-of-class 42 // definition (in a single compilation unit), but MSVC chokes on this (when 43 // language extensions, which are required, are enabled). (You're only likely to 44 // notice the need for a definition if you take the address of the member or, 45 // more commonly, pass it to a function that takes it as a reference argument -- 46 // probably an STL function.) This macro makes MSVC do the right thing. See 47 // http://msdn.microsoft.com/en-us/library/34h23df8(v=vs.100).aspx for more 48 // information. Use like: 49 // 50 // In .h file: 51 // struct Foo { 52 // static const int kBar = 5; 53 // }; 54 // 55 // In .cc file: 56 // STATIC_CONST_MEMBER_DEFINITION const int Foo::kBar; 57 #if V8_HAS_DECLSPEC_SELECTANY 58 #define STATIC_CONST_MEMBER_DEFINITION __declspec(selectany) 59 #else 60 #define STATIC_CONST_MEMBER_DEFINITION 61 #endif 62 63 #if V8_CC_MSVC 64 65 #include <sal.h> 66 67 // Macros for suppressing and disabling warnings on MSVC. 68 // 69 // Warning numbers are enumerated at: 70 // http://msdn.microsoft.com/en-us/library/8x5x43k7(VS.80).aspx 71 // 72 // The warning pragma: 73 // http://msdn.microsoft.com/en-us/library/2c8f766e(VS.80).aspx 74 // 75 // Using __pragma instead of #pragma inside macros: 76 // http://msdn.microsoft.com/en-us/library/d9x1s805.aspx 77 78 // MSVC_SUPPRESS_WARNING disables warning |n| for the remainder of the line and 79 // for the next line of the source file. 80 #define MSVC_SUPPRESS_WARNING(n) __pragma(warning(suppress : n)) 81 82 // Allows exporting a class that inherits from a non-exported base class. 83 // This uses suppress instead of push/pop because the delimiter after the 84 // declaration (either "," or "{") has to be placed before the pop macro. 85 // 86 // Example usage: 87 // class EXPORT_API Foo : NON_EXPORTED_BASE(public Bar) { 88 // 89 // MSVC Compiler warning C4275: 90 // non dll-interface class 'Bar' used as base for dll-interface class 'Foo'. 91 // Note that this is intended to be used only when no access to the base class' 92 // static data is done through derived classes or inline methods. For more info, 93 // see http://msdn.microsoft.com/en-us/library/3tdb471s(VS.80).aspx 94 #define NON_EXPORTED_BASE(code) \ 95 MSVC_SUPPRESS_WARNING(4275) \ 96 code 97 98 #else // Not MSVC 99 100 #define MSVC_SUPPRESS_WARNING(n) 101 #define NON_EXPORTED_BASE(code) code 102 103 #endif // V8_CC_MSVC 104 105 #endif // V8_BASE_COMPILER_SPECIFIC_H_ 106