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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Implementations of various class and method modifier attributes. */
+
+#ifndef mozilla_Attributes_h
+#define mozilla_Attributes_h
+
+#include "mozilla/Compiler.h"
+
+/*
+ * MOZ_ALWAYS_INLINE is a macro which expands to tell the compiler that the
+ * method decorated with it must be inlined, even if the compiler thinks
+ * otherwise. This is only a (much) stronger version of the inline hint:
+ * compilers are not guaranteed to respect it (although they're much more likely
+ * to do so).
+ *
+ * The MOZ_ALWAYS_INLINE_EVEN_DEBUG macro is yet stronger. It tells the
+ * compiler to inline even in DEBUG builds. It should be used very rarely.
+ */
+#if defined(_MSC_VER)
+# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __forceinline
+#elif defined(__GNUC__)
+# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __attribute__((always_inline)) inline
+#else
+# define MOZ_ALWAYS_INLINE_EVEN_DEBUG inline
+#endif
+
+#if !defined(DEBUG)
+# define MOZ_ALWAYS_INLINE MOZ_ALWAYS_INLINE_EVEN_DEBUG
+#elif defined(_MSC_VER) && !defined(__cplusplus)
+# define MOZ_ALWAYS_INLINE __inline
+#else
+# define MOZ_ALWAYS_INLINE inline
+#endif
+
+#if defined(_MSC_VER)
+/*
+ * g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality
+ * without warnings (functionality used by the macros below). These modes are
+ * detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or, more
+ * standardly, by checking whether __cplusplus has a C++11 or greater value.
+ * Current versions of g++ do not correctly set __cplusplus, so we check both
+ * for forward compatibility.
+ */
+# define MOZ_HAVE_NEVER_INLINE __declspec(noinline)
+# define MOZ_HAVE_NORETURN __declspec(noreturn)
+#elif defined(__clang__)
+ /*
+ * Per Clang documentation, "Note that marketing version numbers should not
+ * be used to check for language features, as different vendors use different
+ * numbering schemes. Instead, use the feature checking macros."
+ */
+# ifndef __has_extension
+# define __has_extension __has_feature /* compatibility, for older versions of clang */
+# endif
+# if __has_attribute(noinline)
+# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline))
+# endif
+# if __has_attribute(noreturn)
+# define MOZ_HAVE_NORETURN __attribute__((noreturn))
+# endif
+#elif defined(__GNUC__)
+# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline))
+# define MOZ_HAVE_NORETURN __attribute__((noreturn))
+#endif
+
+/*
+ * When built with clang analyzer (a.k.a scan-build), define MOZ_HAVE_NORETURN
+ * to mark some false positives
+ */
+#ifdef __clang_analyzer__
+# if __has_extension(attribute_analyzer_noreturn)
+# define MOZ_HAVE_ANALYZER_NORETURN __attribute__((analyzer_noreturn))
+# endif
+#endif
+
+/*
+ * MOZ_NEVER_INLINE is a macro which expands to tell the compiler that the
+ * method decorated with it must never be inlined, even if the compiler would
+ * otherwise choose to inline the method. Compilers aren't absolutely
+ * guaranteed to support this, but most do.
+ */
+#if defined(MOZ_HAVE_NEVER_INLINE)
+# define MOZ_NEVER_INLINE MOZ_HAVE_NEVER_INLINE
+#else
+# define MOZ_NEVER_INLINE /* no support */
+#endif
+
+/*
+ * MOZ_NORETURN, specified at the start of a function declaration, indicates
+ * that the given function does not return. (The function definition does not
+ * need to be annotated.)
+ *
+ * MOZ_NORETURN void abort(const char* msg);
+ *
+ * This modifier permits the compiler to optimize code assuming a call to such a
+ * function will never return. It also enables the compiler to avoid spurious
+ * warnings about not initializing variables, or about any other seemingly-dodgy
+ * operations performed after the function returns.
+ *
+ * This modifier does not affect the corresponding function's linking behavior.
+ */
+#if defined(MOZ_HAVE_NORETURN)
+# define MOZ_NORETURN MOZ_HAVE_NORETURN
+#else
+# define MOZ_NORETURN /* no support */
+#endif
+
+/**
+ * MOZ_COLD tells the compiler that a function is "cold", meaning infrequently
+ * executed. This may lead it to optimize for size more aggressively than speed,
+ * or to allocate the body of the function in a distant part of the text segment
+ * to help keep it from taking up unnecessary icache when it isn't in use.
+ *
+ * Place this attribute at the very beginning of a function definition. For
+ * example, write
+ *
+ * MOZ_COLD int foo();
+ *
+ * or
+ *
+ * MOZ_COLD int foo() { return 42; }
+ */
+#if defined(__GNUC__) || defined(__clang__)
+# define MOZ_COLD __attribute__ ((cold))
+#else
+# define MOZ_COLD
+#endif
+
+/**
+ * MOZ_NONNULL tells the compiler that some of the arguments to a function are
+ * known to be non-null. The arguments are a list of 1-based argument indexes
+ * identifying arguments which are known to be non-null.
+ *
+ * Place this attribute at the very beginning of a function definition. For
+ * example, write
+ *
+ * MOZ_NONNULL(1, 2) int foo(char *p, char *q);
+ */
+#if defined(__GNUC__) || defined(__clang__)
+# define MOZ_NONNULL(...) __attribute__ ((nonnull(__VA_ARGS__)))
+#else
+# define MOZ_NONNULL(...)
+#endif
+
+/*
+ * MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS, specified at the end of a function
+ * declaration, indicates that for the purposes of static analysis, this
+ * function does not return. (The function definition does not need to be
+ * annotated.)
+ *
+ * MOZ_ReportCrash(const char* s, const char* file, int ln)
+ * MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS
+ *
+ * Some static analyzers, like scan-build from clang, can use this information
+ * to eliminate false positives. From the upstream documentation of scan-build:
+ * "This attribute is useful for annotating assertion handlers that actually
+ * can return, but for the purpose of using the analyzer we want to pretend
+ * that such functions do not return."
+ *
+ */
+#if defined(MOZ_HAVE_ANALYZER_NORETURN)
+# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS MOZ_HAVE_ANALYZER_NORETURN
+#else
+# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS /* no support */
+#endif
+
+/*
+ * MOZ_ASAN_BLACKLIST is a macro to tell AddressSanitizer (a compile-time
+ * instrumentation shipped with Clang and GCC) to not instrument the annotated
+ * function. Furthermore, it will prevent the compiler from inlining the
+ * function because inlining currently breaks the blacklisting mechanism of
+ * AddressSanitizer.
+ */
+#if defined(__has_feature)
+# if __has_feature(address_sanitizer)
+# define MOZ_HAVE_ASAN_BLACKLIST
+# endif
+#elif defined(__GNUC__)
+# if defined(__SANITIZE_ADDRESS__)
+# define MOZ_HAVE_ASAN_BLACKLIST
+# endif
+#endif
+
+#if defined(MOZ_HAVE_ASAN_BLACKLIST)
+# define MOZ_ASAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_address))
+#else
+# define MOZ_ASAN_BLACKLIST /* nothing */
+#endif
+
+/*
+ * MOZ_TSAN_BLACKLIST is a macro to tell ThreadSanitizer (a compile-time
+ * instrumentation shipped with Clang) to not instrument the annotated function.
+ * Furthermore, it will prevent the compiler from inlining the function because
+ * inlining currently breaks the blacklisting mechanism of ThreadSanitizer.
+ */
+#if defined(__has_feature)
+# if __has_feature(thread_sanitizer)
+# define MOZ_TSAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_thread))
+# else
+# define MOZ_TSAN_BLACKLIST /* nothing */
+# endif
+#else
+# define MOZ_TSAN_BLACKLIST /* nothing */
+#endif
+
+/**
+ * MOZ_ALLOCATOR tells the compiler that the function it marks returns either a
+ * "fresh", "pointer-free" block of memory, or nullptr. "Fresh" means that the
+ * block is not pointed to by any other reachable pointer in the program.
+ * "Pointer-free" means that the block contains no pointers to any valid object
+ * in the program. It may be initialized with other (non-pointer) values.
+ *
+ * Placing this attribute on appropriate functions helps GCC analyze pointer
+ * aliasing more accurately in their callers.
+ *
+ * GCC warns if a caller ignores the value returned by a function marked with
+ * MOZ_ALLOCATOR: it is hard to imagine cases where dropping the value returned
+ * by a function that meets the criteria above would be intentional.
+ *
+ * Place this attribute after the argument list and 'this' qualifiers of a
+ * function definition. For example, write
+ *
+ * void *my_allocator(size_t) MOZ_ALLOCATOR;
+ *
+ * or
+ *
+ * void *my_allocator(size_t bytes) MOZ_ALLOCATOR { ... }
+ */
+#if defined(__GNUC__) || defined(__clang__)
+# define MOZ_ALLOCATOR __attribute__ ((malloc, warn_unused_result))
+#else
+# define MOZ_ALLOCATOR
+#endif
+
+/**
+ * MOZ_MUST_USE tells the compiler to emit a warning if a function's
+ * return value is not used by the caller.
+ *
+ * Place this attribute at the very beginning of a function declaration. For
+ * example, write
+ *
+ * MOZ_MUST_USE int foo();
+ *
+ * or
+ *
+ * MOZ_MUST_USE int foo() { return 42; }
+ */
+#if defined(__GNUC__) || defined(__clang__)
+# define MOZ_MUST_USE __attribute__ ((warn_unused_result))
+#else
+# define MOZ_MUST_USE
+#endif
+
+/**
+ * MOZ_FALLTHROUGH is an annotation to suppress compiler warnings about switch
+ * cases that fall through without a break or return statement. MOZ_FALLTHROUGH
+ * is only needed on cases that have code.
+ *
+ * MOZ_FALLTHROUGH_ASSERT is an annotation to suppress compiler warnings about
+ * switch cases that MOZ_ASSERT(false) (or its alias MOZ_ASSERT_UNREACHABLE) in
+ * debug builds, but intentionally fall through in release builds. See comment
+ * in Assertions.h for more details.
+ *
+ * switch (foo) {
+ * case 1: // These cases have no code. No fallthrough annotations are needed.
+ * case 2:
+ * case 3: // This case has code, so a fallthrough annotation is needed!
+ * foo++;
+ * MOZ_FALLTHROUGH;
+ * case 4:
+ * return foo;
+ *
+ * default:
+ * // This case asserts in debug builds, falls through in release.
+ * MOZ_FALLTHROUGH_ASSERT("Unexpected foo value?!");
+ * case 5:
+ * return 5;
+ * }
+ */
+#if defined(__clang__) && __cplusplus >= 201103L
+ /* clang's fallthrough annotations are only available starting in C++11. */
+# define MOZ_FALLTHROUGH [[clang::fallthrough]]
+#elif defined(_MSC_VER)
+ /*
+ * MSVC's __fallthrough annotations are checked by /analyze (Code Analysis):
+ * https://msdn.microsoft.com/en-us/library/ms235402%28VS.80%29.aspx
+ */
+# include <sal.h>
+# define MOZ_FALLTHROUGH __fallthrough
+#else
+# define MOZ_FALLTHROUGH /* FALLTHROUGH */
+#endif
+
+#ifdef __cplusplus
+
+/*
+ * The following macros are attributes that support the static analysis plugin
+ * included with Mozilla, and will be implemented (when such support is enabled)
+ * as C++11 attributes. Since such attributes are legal pretty much everywhere
+ * and have subtly different semantics depending on their placement, the
+ * following is a guide on where to place the attributes.
+ *
+ * Attributes that apply to a struct or class precede the name of the class:
+ * (Note that this is different from the placement of final for classes!)
+ *
+ * class MOZ_CLASS_ATTRIBUTE SomeClass {};
+ *
+ * Attributes that apply to functions follow the parentheses and const
+ * qualifiers but precede final, override and the function body:
+ *
+ * void DeclaredFunction() MOZ_FUNCTION_ATTRIBUTE;
+ * void SomeFunction() MOZ_FUNCTION_ATTRIBUTE {}
+ * void PureFunction() const MOZ_FUNCTION_ATTRIBUTE = 0;
+ * void OverriddenFunction() MOZ_FUNCTION_ATTIRBUTE override;
+ *
+ * Attributes that apply to variables or parameters follow the variable's name:
+ *
+ * int variable MOZ_VARIABLE_ATTRIBUTE;
+ *
+ * Attributes that apply to types follow the type name:
+ *
+ * typedef int MOZ_TYPE_ATTRIBUTE MagicInt;
+ * int MOZ_TYPE_ATTRIBUTE someVariable;
+ * int* MOZ_TYPE_ATTRIBUTE magicPtrInt;
+ * int MOZ_TYPE_ATTRIBUTE* ptrToMagicInt;
+ *
+ * Attributes that apply to statements precede the statement:
+ *
+ * MOZ_IF_ATTRIBUTE if (x == 0)
+ * MOZ_DO_ATTRIBUTE do { } while (0);
+ *
+ * Attributes that apply to labels precede the label:
+ *
+ * MOZ_LABEL_ATTRIBUTE target:
+ * goto target;
+ * MOZ_CASE_ATTRIBUTE case 5:
+ * MOZ_DEFAULT_ATTRIBUTE default:
+ *
+ * The static analyses that are performed by the plugin are as follows:
+ *
+ * MOZ_MUST_OVERRIDE: Applies to all C++ member functions. All immediate
+ * subclasses must provide an exact override of this method; if a subclass
+ * does not override this method, the compiler will emit an error. This
+ * attribute is not limited to virtual methods, so if it is applied to a
+ * nonvirtual method and the subclass does not provide an equivalent
+ * definition, the compiler will emit an error.
+ * MOZ_STACK_CLASS: Applies to all classes. Any class with this annotation is
+ * expected to live on the stack, so it is a compile-time error to use it, or
+ * an array of such objects, as a global or static variable, or as the type of
+ * a new expression (unless placement new is being used). If a member of
+ * another class uses this class, or if another class inherits from this
+ * class, then it is considered to be a stack class as well, although this
+ * attribute need not be provided in such cases.
+ * MOZ_NONHEAP_CLASS: Applies to all classes. Any class with this annotation is
+ * expected to live on the stack or in static storage, so it is a compile-time
+ * error to use it, or an array of such objects, as the type of a new
+ * expression. If a member of another class uses this class, or if another
+ * class inherits from this class, then it is considered to be a non-heap class
+ * as well, although this attribute need not be provided in such cases.
+ * MOZ_HEAP_CLASS: Applies to all classes. Any class with this annotation is
+ * expected to live on the heap, so it is a compile-time error to use it, or
+ * an array of such objects, as the type of a variable declaration, or as a
+ * temporary object. If a member of another class uses this class, or if
+ * another class inherits from this class, then it is considered to be a heap
+ * class as well, although this attribute need not be provided in such cases.
+ * MOZ_NON_TEMPORARY_CLASS: Applies to all classes. Any class with this
+ * annotation is expected not to live in a temporary. If a member of another
+ * class uses this class or if another class inherits from this class, then it
+ * is considered to be a non-temporary class as well, although this attribute
+ * need not be provided in such cases.
+ * 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_TYPE: 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_NEEDS_MEMMOVABLE_MEMBERS: Applies to class declarations where each member
+ * must be safe to move in memory using memmove(). MOZ_NON_MEMMOVABLE types
+ * used in members of these classes are compile time errors.
+ * 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_TYPE and MOZ_STACK_CLASS) from its template arguments.
+ * MOZ_INIT_OUTSIDE_CTOR: Applies to class member declarations. Occasionally
+ * there are class members that are not initialized in the constructor,
+ * but logic elsewhere in the class ensures they are initialized prior to use.
+ * Using this attribute on a member disables the check that this member must be
+ * initialized in constructors via list-initialization, in the constructor body,
+ * or via functions called from the constructor body.
+ * MOZ_IS_CLASS_INIT: Applies to class method declarations. Occasionally the
+ * constructor doesn't initialize all of the member variables and another function
+ * is used to initialize the rest. This marker is used to make the static analysis
+ * tool aware that the marked function is part of the initialization process
+ * and to include the marked function in the scan mechanism that determines witch
+ * member variables still remain uninitialized.
+ * MOZ_NON_PARAM: Applies to types. Makes it compile time error to use the type
+ * in parameter without pointer or reference.
+ * 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.
+ * MOZ_REQUIRED_BASE_METHOD: Applies to virtual class method declarations.
+ * Sometimes derived classes override methods that need to be called by their
+ * overridden counterparts. This marker indicates that the marked method must
+ * be called by the method that it overrides.
+ */
+#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_TYPE __attribute__((annotate("moz_must_use_type")))
+# 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_NEEDS_MEMMOVABLE_MEMBERS __attribute__((annotate("moz_needs_memmovable_members")))
+# 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")))
+# define MOZ_INIT_OUTSIDE_CTOR \
+ __attribute__((annotate("moz_ignore_ctor_initialization")))
+# define MOZ_IS_CLASS_INIT \
+ __attribute__((annotate("moz_is_class_init")))
+# define MOZ_NON_PARAM \
+ __attribute__((annotate("moz_non_param")))
+# define MOZ_REQUIRED_BASE_METHOD \
+ __attribute__((annotate("moz_required_base_method")))
+/*
+ * 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_TYPE /* nothing */
+# define MOZ_NEEDS_NO_VTABLE_TYPE /* nothing */
+# define MOZ_NON_MEMMOVABLE /* nothing */
+# define MOZ_NEEDS_MEMMOVABLE_TYPE /* nothing */
+# define MOZ_NEEDS_MEMMOVABLE_MEMBERS /* nothing */
+# define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS /* nothing */
+# define MOZ_INIT_OUTSIDE_CTOR /* nothing */
+# define MOZ_IS_CLASS_INIT /* nothing */
+# define MOZ_NON_PARAM /* nothing */
+# define MOZ_NON_AUTOABLE /* nothing */
+# define MOZ_REQUIRED_BASE_METHOD /* 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 */
+
+/**
+ * Printf style formats. MOZ_FORMAT_PRINTF can be used to annotate a
+ * function or method that is "printf-like"; this will let (some)
+ * compilers check that the arguments match the template string.
+ *
+ * This macro takes two arguments. The first argument is the argument
+ * number of the template string. The second argument is the argument
+ * number of the '...' argument holding the arguments.
+ *
+ * Argument numbers start at 1. Note that the implicit "this"
+ * argument of a non-static member function counts as an argument.
+ *
+ * So, for a simple case like:
+ * void print_something (int whatever, const char *fmt, ...);
+ * The corresponding annotation would be
+ * MOZ_FORMAT_PRINTF(2, 3)
+ * However, if "print_something" were a non-static member function,
+ * then the annotation would be:
+ * MOZ_FORMAT_PRINTF(3, 4)
+ *
+ * Note that the checking is limited to standards-conforming
+ * printf-likes, and in particular this should not be used for
+ * PR_snprintf and friends, which are "printf-like" but which assign
+ * different meanings to the various formats.
+ */
+#ifdef __GNUC__
+#define MOZ_FORMAT_PRINTF(stringIndex, firstToCheck) \
+ __attribute__ ((format (printf, stringIndex, firstToCheck)))
+#else
+#define MOZ_FORMAT_PRINTF(stringIndex, firstToCheck)
+#endif
+
+#endif /* mozilla_Attributes_h */