mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-28 15:23:51 +00:00
a240a28c7f
constexpr-ness of things can change the ABI requirements, and MSVC 2013 doesn't support constexpr, so choosing it for clang-cl when emulating MSVC 2013 will cause ABI incomap issues between object files compiled with the two compilers. This reverts part of the commit for the original bug.
615 lines
26 KiB
C++
615 lines
26 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/* Implementations of various class and method modifier attributes. */
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#ifndef mozilla_Attributes_h
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#define mozilla_Attributes_h
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#include "mozilla/Compiler.h"
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/*
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* MOZ_ALWAYS_INLINE is a macro which expands to tell the compiler that the
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* method decorated with it must be inlined, even if the compiler thinks
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* otherwise. This is only a (much) stronger version of the inline hint:
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* compilers are not guaranteed to respect it (although they're much more likely
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* to do so).
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*
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* The MOZ_ALWAYS_INLINE_EVEN_DEBUG macro is yet stronger. It tells the
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* compiler to inline even in DEBUG builds. It should be used very rarely.
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*/
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#if defined(_MSC_VER)
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# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __forceinline
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#elif defined(__GNUC__)
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# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __attribute__((always_inline)) inline
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#else
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# define MOZ_ALWAYS_INLINE_EVEN_DEBUG inline
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#endif
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#if !defined(DEBUG)
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# define MOZ_ALWAYS_INLINE MOZ_ALWAYS_INLINE_EVEN_DEBUG
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#elif defined(_MSC_VER) && !defined(__cplusplus)
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# define MOZ_ALWAYS_INLINE __inline
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#else
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# define MOZ_ALWAYS_INLINE inline
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#endif
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#if defined(_MSC_VER)
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/*
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* g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality
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* without warnings (functionality used by the macros below). These modes are
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* detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or, more
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* standardly, by checking whether __cplusplus has a C++11 or greater value.
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* Current versions of g++ do not correctly set __cplusplus, so we check both
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* for forward compatibility.
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*
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* Even though some versions of MSVC support explicit conversion operators, we
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* don't indicate support for them here, due to
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* http://stackoverflow.com/questions/20498142/visual-studio-2013-explicit-keyword-bug
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*/
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# define MOZ_HAVE_NEVER_INLINE __declspec(noinline)
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# define MOZ_HAVE_NORETURN __declspec(noreturn)
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# if _MSC_VER >= 1900
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# define MOZ_HAVE_CXX11_CONSTEXPR
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# define MOZ_HAVE_CXX11_CONSTEXPR_IN_TEMPLATES
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# define MOZ_HAVE_EXPLICIT_CONVERSION
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# endif
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# ifdef __clang__
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/* clang-cl probably supports explicit conversions. */
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# if __has_extension(cxx_explicit_conversions)
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# define MOZ_HAVE_EXPLICIT_CONVERSION
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# endif
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# endif
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#elif defined(__clang__)
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/*
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* Per Clang documentation, "Note that marketing version numbers should not
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* be used to check for language features, as different vendors use different
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* numbering schemes. Instead, use the feature checking macros."
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*/
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# ifndef __has_extension
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# define __has_extension __has_feature /* compatibility, for older versions of clang */
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# endif
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# if __has_extension(cxx_constexpr)
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# define MOZ_HAVE_CXX11_CONSTEXPR
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# endif
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# if __has_extension(cxx_explicit_conversions)
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# define MOZ_HAVE_EXPLICIT_CONVERSION
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# endif
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# if __has_attribute(noinline)
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# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline))
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# endif
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# if __has_attribute(noreturn)
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# define MOZ_HAVE_NORETURN __attribute__((noreturn))
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# endif
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#elif defined(__GNUC__)
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# if defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L
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# define MOZ_HAVE_CXX11_CONSTEXPR
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# if MOZ_GCC_VERSION_AT_LEAST(4, 8, 0)
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# define MOZ_HAVE_CXX11_CONSTEXPR_IN_TEMPLATES
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# endif
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# define MOZ_HAVE_EXPLICIT_CONVERSION
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# endif
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# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline))
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# define MOZ_HAVE_NORETURN __attribute__((noreturn))
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#endif
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/*
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* When built with clang analyzer (a.k.a scan-build), define MOZ_HAVE_NORETURN
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* to mark some false positives
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*/
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#ifdef __clang_analyzer__
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# if __has_extension(attribute_analyzer_noreturn)
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# define MOZ_HAVE_ANALYZER_NORETURN __attribute__((analyzer_noreturn))
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# endif
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#endif
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/*
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* The MOZ_CONSTEXPR specifier declares that a C++11 compiler can evaluate a
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* function at compile time. A constexpr function cannot examine any values
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* except its arguments and can have no side effects except its return value.
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* The MOZ_CONSTEXPR_VAR specifier tells a C++11 compiler that a variable's
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* value may be computed at compile time. It should be prefered to just
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* marking variables as MOZ_CONSTEXPR because if the compiler does not support
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* constexpr it will fall back to making the variable const, and some compilers
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* do not accept variables being marked both const and constexpr.
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*/
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#ifdef MOZ_HAVE_CXX11_CONSTEXPR
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# define MOZ_CONSTEXPR constexpr
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# define MOZ_CONSTEXPR_VAR constexpr
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# ifdef MOZ_HAVE_CXX11_CONSTEXPR_IN_TEMPLATES
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# define MOZ_CONSTEXPR_TMPL constexpr
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# else
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# define MOZ_CONSTEXPR_TMPL
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# endif
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#else
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# define MOZ_CONSTEXPR /* no support */
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# define MOZ_CONSTEXPR_VAR const
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# define MOZ_CONSTEXPR_TMPL
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#endif
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/*
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* MOZ_EXPLICIT_CONVERSION is a specifier on a type conversion
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* overloaded operator that declares that a C++11 compiler should restrict
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* this operator to allow only explicit type conversions, disallowing
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* implicit conversions.
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*
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* Example:
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*
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* template<typename T>
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* class Ptr
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* {
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* T* mPtr;
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* MOZ_EXPLICIT_CONVERSION operator bool() const
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* {
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* return mPtr != nullptr;
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* }
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* };
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*
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*/
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#ifdef MOZ_HAVE_EXPLICIT_CONVERSION
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# define MOZ_EXPLICIT_CONVERSION explicit
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#else
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# define MOZ_EXPLICIT_CONVERSION /* no support */
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#endif
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/*
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* MOZ_NEVER_INLINE is a macro which expands to tell the compiler that the
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* method decorated with it must never be inlined, even if the compiler would
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* otherwise choose to inline the method. Compilers aren't absolutely
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* guaranteed to support this, but most do.
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*/
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#if defined(MOZ_HAVE_NEVER_INLINE)
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# define MOZ_NEVER_INLINE MOZ_HAVE_NEVER_INLINE
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#else
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# define MOZ_NEVER_INLINE /* no support */
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#endif
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/*
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* MOZ_NORETURN, specified at the start of a function declaration, indicates
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* that the given function does not return. (The function definition does not
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* need to be annotated.)
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*
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* MOZ_NORETURN void abort(const char* msg);
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*
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* This modifier permits the compiler to optimize code assuming a call to such a
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* function will never return. It also enables the compiler to avoid spurious
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* warnings about not initializing variables, or about any other seemingly-dodgy
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* operations performed after the function returns.
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*
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* This modifier does not affect the corresponding function's linking behavior.
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*/
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#if defined(MOZ_HAVE_NORETURN)
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# define MOZ_NORETURN MOZ_HAVE_NORETURN
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#else
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# define MOZ_NORETURN /* no support */
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#endif
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/**
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* MOZ_COLD tells the compiler that a function is "cold", meaning infrequently
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* executed. This may lead it to optimize for size more aggressively than speed,
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* or to allocate the body of the function in a distant part of the text segment
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* to help keep it from taking up unnecessary icache when it isn't in use.
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*
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* Place this attribute at the very beginning of a function definition. For
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* example, write
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*
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* MOZ_COLD int foo();
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*
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* or
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*
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* MOZ_COLD int foo() { return 42; }
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*/
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#if defined(__GNUC__) || defined(__clang__)
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# define MOZ_COLD __attribute__ ((cold))
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#else
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# define MOZ_COLD
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#endif
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/**
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* MOZ_NONNULL tells the compiler that some of the arguments to a function are
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* known to be non-null. The arguments are a list of 1-based argument indexes
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* identifying arguments which are known to be non-null.
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*
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* Place this attribute at the very beginning of a function definition. For
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* example, write
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*
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* MOZ_NONNULL(1, 2) int foo(char *p, char *q);
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*/
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#if defined(__GNUC__) || defined(__clang__)
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# define MOZ_NONNULL(...) __attribute__ ((nonnull(__VA_ARGS__)))
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#else
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# define MOZ_NONNULL(...)
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#endif
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/*
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* MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS, specified at the end of a function
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* declaration, indicates that for the purposes of static analysis, this
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* function does not return. (The function definition does not need to be
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* annotated.)
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*
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* MOZ_ReportCrash(const char* s, const char* file, int ln)
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* MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS
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*
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* Some static analyzers, like scan-build from clang, can use this information
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* to eliminate false positives. From the upstream documentation of scan-build:
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* "This attribute is useful for annotating assertion handlers that actually
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* can return, but for the purpose of using the analyzer we want to pretend
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* that such functions do not return."
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*
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*/
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#if defined(MOZ_HAVE_ANALYZER_NORETURN)
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# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS MOZ_HAVE_ANALYZER_NORETURN
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#else
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# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS /* no support */
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#endif
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/*
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* MOZ_ASAN_BLACKLIST is a macro to tell AddressSanitizer (a compile-time
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* instrumentation shipped with Clang and GCC) to not instrument the annotated
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* function. Furthermore, it will prevent the compiler from inlining the
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* function because inlining currently breaks the blacklisting mechanism of
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* AddressSanitizer.
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*/
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#if defined(__has_feature)
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# if __has_feature(address_sanitizer)
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# define MOZ_HAVE_ASAN_BLACKLIST
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# endif
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#elif defined(__GNUC__)
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# if defined(__SANITIZE_ADDRESS__)
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# define MOZ_HAVE_ASAN_BLACKLIST
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# endif
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#endif
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#if defined(MOZ_HAVE_ASAN_BLACKLIST)
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# define MOZ_ASAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_address))
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#else
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# define MOZ_ASAN_BLACKLIST /* nothing */
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#endif
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/*
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* MOZ_TSAN_BLACKLIST is a macro to tell ThreadSanitizer (a compile-time
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* instrumentation shipped with Clang) to not instrument the annotated function.
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* Furthermore, it will prevent the compiler from inlining the function because
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* inlining currently breaks the blacklisting mechanism of ThreadSanitizer.
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*/
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#if defined(__has_feature)
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# if __has_feature(thread_sanitizer)
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# define MOZ_TSAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_thread))
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# else
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# define MOZ_TSAN_BLACKLIST /* nothing */
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# endif
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#else
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# define MOZ_TSAN_BLACKLIST /* nothing */
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#endif
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/**
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* MOZ_ALLOCATOR tells the compiler that the function it marks returns either a
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* "fresh", "pointer-free" block of memory, or nullptr. "Fresh" means that the
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* block is not pointed to by any other reachable pointer in the program.
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* "Pointer-free" means that the block contains no pointers to any valid object
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* in the program. It may be initialized with other (non-pointer) values.
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*
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* Placing this attribute on appropriate functions helps GCC analyze pointer
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* aliasing more accurately in their callers.
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*
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* GCC warns if a caller ignores the value returned by a function marked with
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* MOZ_ALLOCATOR: it is hard to imagine cases where dropping the value returned
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* by a function that meets the criteria above would be intentional.
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*
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* Place this attribute after the argument list and 'this' qualifiers of a
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* function definition. For example, write
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*
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* void *my_allocator(size_t) MOZ_ALLOCATOR;
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*
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* or
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*
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* void *my_allocator(size_t bytes) MOZ_ALLOCATOR { ... }
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*/
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#if defined(__GNUC__) || defined(__clang__)
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# define MOZ_ALLOCATOR __attribute__ ((malloc, warn_unused_result))
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#else
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# define MOZ_ALLOCATOR
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#endif
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/**
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* MOZ_WARN_UNUSED_RESULT tells the compiler to emit a warning if a function's
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* return value is not used by the caller.
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*
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* Place this attribute at the very beginning of a function definition. For
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* example, write
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*
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* MOZ_WARN_UNUSED_RESULT int foo();
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*
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* or
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*
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* MOZ_WARN_UNUSED_RESULT int foo() { return 42; }
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*/
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#if defined(__GNUC__) || defined(__clang__)
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# define MOZ_WARN_UNUSED_RESULT __attribute__ ((warn_unused_result))
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#else
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# define MOZ_WARN_UNUSED_RESULT
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#endif
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/**
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* MOZ_FALLTHROUGH is an annotation to suppress compiler warnings about switch
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* cases that fall through without a break or return statement. MOZ_FALLTHROUGH
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* is only needed on cases that have code.
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*
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* MOZ_FALLTHROUGH_ASSERT is an annotation to suppress compiler warnings about
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* switch cases that MOZ_ASSERT(false) (or its alias MOZ_ASSERT_UNREACHABLE) in
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* debug builds, but intentionally fall through in release builds. See comment
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* in Assertions.h for more details.
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*
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* switch (foo) {
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* case 1: // These cases have no code. No fallthrough annotations are needed.
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* case 2:
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* case 3: // This case has code, so a fallthrough annotation is needed!
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* foo++;
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* MOZ_FALLTHROUGH;
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* case 4:
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* return foo;
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*
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* default:
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* // This case asserts in debug builds, falls through in release.
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* MOZ_FALLTHROUGH_ASSERT("Unexpected foo value?!");
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* case 5:
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* return 5;
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* }
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*/
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#if defined(__clang__) && __cplusplus >= 201103L
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/* clang's fallthrough annotations are only available starting in C++11. */
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# define MOZ_FALLTHROUGH [[clang::fallthrough]]
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#elif defined(_MSC_VER)
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/*
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* MSVC's __fallthrough annotations are checked by /analyze (Code Analysis):
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* https://msdn.microsoft.com/en-us/library/ms235402%28VS.80%29.aspx
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*/
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# include <sal.h>
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# define MOZ_FALLTHROUGH __fallthrough
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#else
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# define MOZ_FALLTHROUGH /* FALLTHROUGH */
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#endif
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#ifdef __cplusplus
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/*
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* The following macros are attributes that support the static analysis plugin
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* included with Mozilla, and will be implemented (when such support is enabled)
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* as C++11 attributes. Since such attributes are legal pretty much everywhere
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* and have subtly different semantics depending on their placement, the
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* following is a guide on where to place the attributes.
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*
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* Attributes that apply to a struct or class precede the name of the class:
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* (Note that this is different from the placement of final for classes!)
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*
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* class MOZ_CLASS_ATTRIBUTE SomeClass {};
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*
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* Attributes that apply to functions follow the parentheses and const
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* qualifiers but precede final, override and the function body:
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*
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* void DeclaredFunction() MOZ_FUNCTION_ATTRIBUTE;
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* void SomeFunction() MOZ_FUNCTION_ATTRIBUTE {}
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* void PureFunction() const MOZ_FUNCTION_ATTRIBUTE = 0;
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* void OverriddenFunction() MOZ_FUNCTION_ATTIRBUTE override;
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*
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* Attributes that apply to variables or parameters follow the variable's name:
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*
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* int variable MOZ_VARIABLE_ATTRIBUTE;
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*
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* Attributes that apply to types follow the type name:
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*
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* typedef int MOZ_TYPE_ATTRIBUTE MagicInt;
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* int MOZ_TYPE_ATTRIBUTE someVariable;
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* int* MOZ_TYPE_ATTRIBUTE magicPtrInt;
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* int MOZ_TYPE_ATTRIBUTE* ptrToMagicInt;
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*
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* Attributes that apply to statements precede the statement:
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*
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* MOZ_IF_ATTRIBUTE if (x == 0)
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* MOZ_DO_ATTRIBUTE do { } while (0);
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*
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* Attributes that apply to labels precede the label:
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*
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* MOZ_LABEL_ATTRIBUTE target:
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* goto target;
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* MOZ_CASE_ATTRIBUTE case 5:
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* MOZ_DEFAULT_ATTRIBUTE default:
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*
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* The static analyses that are performed by the plugin are as follows:
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*
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* MOZ_MUST_OVERRIDE: Applies to all C++ member functions. All immediate
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* subclasses must provide an exact override of this method; if a subclass
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* does not override this method, the compiler will emit an error. This
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* attribute is not limited to virtual methods, so if it is applied to a
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* nonvirtual method and the subclass does not provide an equivalent
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* definition, the compiler will emit an error.
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* MOZ_STACK_CLASS: Applies to all classes. Any class with this annotation is
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* expected to live on the stack, so it is a compile-time error to use it, or
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* an array of such objects, as a global or static variable, or as the type of
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* a new expression (unless placement new is being used). If a member of
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* another class uses this class, or if another class inherits from this
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* class, then it is considered to be a stack class as well, although this
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* attribute need not be provided in such cases.
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* MOZ_NONHEAP_CLASS: Applies to all classes. Any class with this annotation is
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* expected to live on the stack or in static storage, so it is a compile-time
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* error to use it, or an array of such objects, as the type of a new
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* expression. If a member of another class uses this class, or if another
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* class inherits from this class, then it is considered to be a non-heap class
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* as well, although this attribute need not be provided in such cases.
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* MOZ_HEAP_CLASS: Applies to all classes. Any class with this annotation is
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* expected to live on the heap, so it is a compile-time error to use it, or
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* an array of such objects, as the type of a variable declaration, or as a
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* temporary object. If a member of another class uses this class, or if
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* another class inherits from this class, then it is considered to be a heap
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* class as well, although this attribute need not be provided in such cases.
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* MOZ_NON_TEMPORARY_CLASS: Applies to all classes. Any class with this
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* annotation is expected not to live in a temporary. If a member of another
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* class uses this class or if another class inherits from this class, then it
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* is considered to be a non-temporary class as well, although this attribute
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* need not be provided in such cases.
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* MOZ_RAII: Applies to all classes. Any class with this annotation is assumed
|
|
* to be a RAII guard, which is expected to live on the stack in an automatic
|
|
* allocation. It is prohibited from being allocated in a temporary, static
|
|
* storage, or on the heap. This is a combination of MOZ_STACK_CLASS and
|
|
* MOZ_NON_TEMPORARY_CLASS.
|
|
* MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS: Applies to all classes that are
|
|
* intended to prevent introducing static initializers. This attribute
|
|
* currently makes it a compile-time error to instantiate these classes
|
|
* anywhere other than at the global scope, or as a static member of a class.
|
|
* In non-debug mode, it also prohibits non-trivial constructors and
|
|
* destructors.
|
|
* MOZ_TRIVIAL_CTOR_DTOR: Applies to all classes that must have both a trivial
|
|
* or constexpr constructor and a trivial destructor. Setting this attribute
|
|
* on a class makes it a compile-time error for that class to get a
|
|
* non-trivial constructor or destructor for any reason.
|
|
* MOZ_HEAP_ALLOCATOR: Applies to any function. This indicates that the return
|
|
* value is allocated on the heap, and will as a result check such allocations
|
|
* during MOZ_STACK_CLASS and MOZ_NONHEAP_CLASS annotation checking.
|
|
* MOZ_IMPLICIT: Applies to constructors. Implicit conversion constructors
|
|
* are disallowed by default unless they are marked as MOZ_IMPLICIT. This
|
|
* attribute must be used for constructors which intend to provide implicit
|
|
* conversions.
|
|
* MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT: Applies to functions. Makes it a compile
|
|
* time error to pass arithmetic expressions on variables to the function.
|
|
* MOZ_OWNING_REF: Applies to declarations of pointers to reference counted
|
|
* types. This attribute tells the compiler that the raw pointer is a strong
|
|
* reference, where ownership through methods such as AddRef and Release is
|
|
* managed manually. This can make the compiler ignore these pointers when
|
|
* validating the usage of pointers otherwise.
|
|
*
|
|
* Example uses include owned pointers inside of unions, and pointers stored
|
|
* in POD types where a using a smart pointer class would make the object
|
|
* non-POD.
|
|
* MOZ_NON_OWNING_REF: Applies to declarations of pointers to reference counted
|
|
* types. This attribute tells the compiler that the raw pointer is a weak
|
|
* reference, which is ensured to be valid by a guarantee that the reference
|
|
* will be nulled before the pointer becomes invalid. This can make the compiler
|
|
* ignore these pointers when validating the usage of pointers otherwise.
|
|
*
|
|
* Examples include an mOwner pointer, which is nulled by the owning class's
|
|
* destructor, and is null-checked before dereferencing.
|
|
* MOZ_UNSAFE_REF: Applies to declarations of pointers to reference counted types.
|
|
* Occasionally there are non-owning references which are valid, but do not take
|
|
* the form of a MOZ_NON_OWNING_REF. Their safety may be dependent on the behaviour
|
|
* of API consumers. The string argument passed to this macro documents the safety
|
|
* conditions. This can make the compiler ignore these pointers when validating
|
|
* the usage of pointers elsewhere.
|
|
*
|
|
* Examples include an nsIAtom* member which is known at compile time to point to a
|
|
* static atom which is valid throughout the lifetime of the program, or an API which
|
|
* stores a pointer, but doesn't take ownership over it, instead requiring the API
|
|
* consumer to correctly null the value before it becomes invalid.
|
|
*
|
|
* Use of this annotation is discouraged when a strong reference or one of the above
|
|
* two annotations can be used instead.
|
|
* MOZ_NO_ADDREF_RELEASE_ON_RETURN: Applies to function declarations. Makes it
|
|
* a compile time error to call AddRef or Release on the return value of a
|
|
* function. This is intended to be used with operator->() of our smart
|
|
* pointer classes to ensure that the refcount of an object wrapped in a
|
|
* smart pointer is not manipulated directly.
|
|
* MOZ_MUST_USE: Applies to type declarations. Makes it a compile time error to not
|
|
* use the return value of a function which has this type. This is intended to be
|
|
* used with types which it is an error to not use.
|
|
* MOZ_NEEDS_NO_VTABLE_TYPE: Applies to template class declarations. Makes it
|
|
* a compile time error to instantiate this template with a type parameter which
|
|
* has a VTable.
|
|
* MOZ_NON_MEMMOVABLE: Applies to class declarations for types that are not safe
|
|
* to be moved in memory using memmove().
|
|
* MOZ_NEEDS_MEMMOVABLE_TYPE: Applies to template class declarations where the
|
|
* template arguments are required to be safe to move in memory using
|
|
* memmove(). Passing MOZ_NON_MEMMOVABLE types to these templates is a
|
|
* compile time error.
|
|
* MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS: Applies to template class
|
|
* declarations where an instance of the template should be considered, for
|
|
* static analysis purposes, to inherit any type annotations (such as
|
|
* MOZ_MUST_USE and MOZ_STACK_CLASS) from its template arguments.
|
|
* MOZ_NON_AUTOABLE: Applies to class declarations. Makes it a compile time error to
|
|
* use `auto` in place of this type in variable declarations. This is intended to
|
|
* be used with types which are intended to be implicitly constructed into other
|
|
* other types before being assigned to variables.
|
|
*/
|
|
#ifdef MOZ_CLANG_PLUGIN
|
|
# define MOZ_MUST_OVERRIDE __attribute__((annotate("moz_must_override")))
|
|
# define MOZ_STACK_CLASS __attribute__((annotate("moz_stack_class")))
|
|
# define MOZ_NONHEAP_CLASS __attribute__((annotate("moz_nonheap_class")))
|
|
# define MOZ_HEAP_CLASS __attribute__((annotate("moz_heap_class")))
|
|
# define MOZ_NON_TEMPORARY_CLASS __attribute__((annotate("moz_non_temporary_class")))
|
|
# define MOZ_TRIVIAL_CTOR_DTOR __attribute__((annotate("moz_trivial_ctor_dtor")))
|
|
# ifdef DEBUG
|
|
/* in debug builds, these classes do have non-trivial constructors. */
|
|
# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS __attribute__((annotate("moz_global_class")))
|
|
# else
|
|
# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS __attribute__((annotate("moz_global_class"))) \
|
|
MOZ_TRIVIAL_CTOR_DTOR
|
|
# endif
|
|
# define MOZ_IMPLICIT __attribute__((annotate("moz_implicit")))
|
|
# define MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT __attribute__((annotate("moz_no_arith_expr_in_arg")))
|
|
# define MOZ_OWNING_REF __attribute__((annotate("moz_strong_ref")))
|
|
# define MOZ_NON_OWNING_REF __attribute__((annotate("moz_weak_ref")))
|
|
# define MOZ_UNSAFE_REF(reason) __attribute__((annotate("moz_weak_ref")))
|
|
# define MOZ_NO_ADDREF_RELEASE_ON_RETURN __attribute__((annotate("moz_no_addref_release_on_return")))
|
|
# define MOZ_MUST_USE __attribute__((annotate("moz_must_use")))
|
|
# define MOZ_NEEDS_NO_VTABLE_TYPE __attribute__((annotate("moz_needs_no_vtable_type")))
|
|
# define MOZ_NON_MEMMOVABLE __attribute__((annotate("moz_non_memmovable")))
|
|
# define MOZ_NEEDS_MEMMOVABLE_TYPE __attribute__((annotate("moz_needs_memmovable_type")))
|
|
# define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS \
|
|
__attribute__((annotate("moz_inherit_type_annotations_from_template_args")))
|
|
# define MOZ_NON_AUTOABLE __attribute__((annotate("moz_non_autoable")))
|
|
/*
|
|
* It turns out that clang doesn't like void func() __attribute__ {} without a
|
|
* warning, so use pragmas to disable the warning. This code won't work on GCC
|
|
* anyways, so the warning is safe to ignore.
|
|
*/
|
|
# define MOZ_HEAP_ALLOCATOR \
|
|
_Pragma("clang diagnostic push") \
|
|
_Pragma("clang diagnostic ignored \"-Wgcc-compat\"") \
|
|
__attribute__((annotate("moz_heap_allocator"))) \
|
|
_Pragma("clang diagnostic pop")
|
|
#else
|
|
# define MOZ_MUST_OVERRIDE /* nothing */
|
|
# define MOZ_STACK_CLASS /* nothing */
|
|
# define MOZ_NONHEAP_CLASS /* nothing */
|
|
# define MOZ_HEAP_CLASS /* nothing */
|
|
# define MOZ_NON_TEMPORARY_CLASS /* nothing */
|
|
# define MOZ_TRIVIAL_CTOR_DTOR /* nothing */
|
|
# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS /* nothing */
|
|
# define MOZ_IMPLICIT /* nothing */
|
|
# define MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT /* nothing */
|
|
# define MOZ_HEAP_ALLOCATOR /* nothing */
|
|
# define MOZ_OWNING_REF /* nothing */
|
|
# define MOZ_NON_OWNING_REF /* nothing */
|
|
# define MOZ_UNSAFE_REF(reason) /* nothing */
|
|
# define MOZ_NO_ADDREF_RELEASE_ON_RETURN /* nothing */
|
|
# define MOZ_MUST_USE /* nothing */
|
|
# define MOZ_NEEDS_NO_VTABLE_TYPE /* nothing */
|
|
# define MOZ_NON_MEMMOVABLE /* nothing */
|
|
# define MOZ_NEEDS_MEMMOVABLE_TYPE /* nothing */
|
|
# define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS /* nothing */
|
|
# define MOZ_NON_AUTOABLE /* nothing */
|
|
#endif /* MOZ_CLANG_PLUGIN */
|
|
|
|
#define MOZ_RAII MOZ_NON_TEMPORARY_CLASS MOZ_STACK_CLASS
|
|
|
|
/*
|
|
* MOZ_HAVE_REF_QUALIFIERS is defined for compilers that support C++11's rvalue
|
|
* qualifier, "&&".
|
|
*/
|
|
#if defined(_MSC_VER) && _MSC_VER >= 1900
|
|
# define MOZ_HAVE_REF_QUALIFIERS
|
|
#elif defined(__clang__)
|
|
// All supported Clang versions
|
|
# define MOZ_HAVE_REF_QUALIFIERS
|
|
#elif defined(__GNUC__)
|
|
# include "mozilla/Compiler.h"
|
|
# if MOZ_GCC_VERSION_AT_LEAST(4, 8, 1)
|
|
# define MOZ_HAVE_REF_QUALIFIERS
|
|
# endif
|
|
#endif
|
|
|
|
#endif /* __cplusplus */
|
|
|
|
#endif /* mozilla_Attributes_h */
|