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/* 
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 * Copyright 2012 David Chisnall. All rights reserved.
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 *
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 * Permission is hereby granted, free of charge, to any person obtaining a copy
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 * of this software and associated documentation files (the "Software"), to
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 * deal in the Software without restriction, including without limitation the
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 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
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 * sell copies of the Software, and to permit persons to whom the Software is
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 * furnished to do so, subject to the following conditions:
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 * 
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 * The above copyright notice and this permission notice shall be
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 * included in all copies or substantial portions of the Software.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
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 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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 */ 
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#ifndef __CXXABI_H_
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#define __CXXABI_H_
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#include <stddef.h>
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#include <stdint.h>
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#include "unwind.h"
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namespace std 
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{
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        class type_info;
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}
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/*
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 * The cxxabi.h header provides a set of public definitions for types and
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 * functions defined by the Itanium C++ ABI specification.  For reference, see
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 * the ABI specification here:
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 *
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 * http://sourcery.mentor.com/public/cxx-abi/abi.html
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 *
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 * All deviations from this specification, unless otherwise noted, are
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 * accidental.
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 */
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#ifdef __cplusplus
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namespace __cxxabiv1 {
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extern "C" {
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#endif
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/**
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 * Function type to call when an unexpected exception is encountered.
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 */
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typedef void (*unexpected_handler)();
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/**
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 * Function type to call when an unrecoverable condition is encountered.
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 */
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typedef void (*terminate_handler)();
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/**
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 * Structure used as a header on thrown exceptions.  This is the same layout as
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 * defined by the Itanium ABI spec, so should be interoperable with any other
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 * implementation of this spec, such as GNU libsupc++.
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 *
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 * This structure is allocated when an exception is thrown.  Unwinding happens
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 * in two phases, the first looks for a handler and the second installs the
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 * context.  This structure stores a cache of the handler location between
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 * phase 1 and phase 2.  Unfortunately, cleanup information is not cached, so
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 * must be looked up in both phases.  This happens for two reasons.  The first
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 * is that we don't know how many frames containing cleanups there will be, and
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 * we should avoid dynamic allocation during unwinding (the exception may be
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 * reporting that we've run out of memory).  The second is that finding
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 * cleanups is much cheaper than finding handlers, because we don't have to
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 * look at the type table at all.
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 *
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 * Note: Several fields of this structure have not-very-informative names.
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 * These are taken from the ABI spec and have not been changed to make it
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 * easier for people referring to to the spec while reading this code.
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 */
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struct __cxa_exception
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{
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#if __LP64__
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        /**
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         * Reference count.  Used to support the C++11 exception_ptr class.  This
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         * is prepended to the structure in 64-bit mode and squeezed in to the
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         * padding left before the 64-bit aligned _Unwind_Exception at the end in
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         * 32-bit mode.
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         *
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         * Note that it is safe to extend this structure at the beginning, rather
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         * than the end, because the public API for creating it returns the address
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         * of the end (where the exception object can be stored).
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         */
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        uintptr_t referenceCount;
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#endif
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        /** Type info for the thrown object. */
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        std::type_info *exceptionType;
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        /** Destructor for the object, if one exists. */
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        void (*exceptionDestructor) (void *); 
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        /** Handler called when an exception specification is violated. */
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        unexpected_handler unexpectedHandler;
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        /** Hander called to terminate. */
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        terminate_handler terminateHandler;
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        /**
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         * Next exception in the list.  If an exception is thrown inside a catch
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         * block and caught in a nested catch, this points to the exception that
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         * will be handled after the inner catch block completes.
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         */
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        __cxa_exception *nextException;
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        /**
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         * The number of handlers that currently have references to this
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         * exception.  The top (non-sign) bit of this is used as a flag to indicate
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         * that the exception is being rethrown, so should not be deleted when its
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         * handler count reaches 0 (which it doesn't with the top bit set).
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         */
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        int handlerCount;
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#if defined(__arm__) && !defined(__ARM_DWARF_EH__)
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        /**
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         * The ARM EH ABI requires the unwind library to keep track of exceptions
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         * during cleanups.  These support nesting, so we need to keep a list of
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         * them.
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         */
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        _Unwind_Exception *nextCleanup;
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        /**
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         * The number of cleanups that are currently being run on this exception. 
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         */
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        int cleanupCount;
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#endif
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        /**
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         * The selector value to be returned when installing the catch handler.
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         * Used at the call site to determine which catch() block should execute.
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         * This is found in phase 1 of unwinding then installed in phase 2.
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         */
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        int handlerSwitchValue;
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        /**
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         * The action record for the catch.  This is cached during phase 1
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         * unwinding.
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         */
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        const char *actionRecord;
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        /**
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         * Pointer to the language-specific data area (LSDA) for the handler
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         * frame.  This is unused in this implementation, but set for ABI
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         * compatibility in case we want to mix code in very weird ways.
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         */
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        const char *languageSpecificData;
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        /** The cached landing pad for the catch handler.*/
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        void *catchTemp;
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        /**
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         * The pointer that will be returned as the pointer to the object.  When
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         * throwing a class and catching a virtual superclass (for example), we
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         * need to adjust the thrown pointer to make it all work correctly.
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         */
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        void *adjustedPtr;
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#if !__LP64__
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        /**
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         * Reference count.  Used to support the C++11 exception_ptr class.  This
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         * is prepended to the structure in 64-bit mode and squeezed in to the
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         * padding left before the 64-bit aligned _Unwind_Exception at the end in
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         * 32-bit mode.
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         *
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         * Note that it is safe to extend this structure at the beginning, rather
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         * than the end, because the public API for creating it returns the address
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         * of the end (where the exception object can be stored) 
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         */
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        uintptr_t referenceCount;
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#endif
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        /** The language-agnostic part of the exception header. */
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        _Unwind_Exception unwindHeader;
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};
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/**
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 * ABI-specified globals structure.  Returned by the __cxa_get_globals()
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 * function and its fast variant.  This is a per-thread structure - every
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 * thread will have one lazily allocated.
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 *
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 * This structure is defined by the ABI, so may be used outside of this
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 * library.
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 */
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struct __cxa_eh_globals
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{
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        /**
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         * A linked list of exceptions that are currently caught.  There may be
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         * several of these in nested catch() blocks.
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         */
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        __cxa_exception *caughtExceptions;
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        /**
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         * The number of uncaught exceptions.
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         */
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        unsigned int uncaughtExceptions;
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};
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/**
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 * ABI function returning the __cxa_eh_globals structure.
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 */
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__cxa_eh_globals *__cxa_get_globals(void);
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/**
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 * Version of __cxa_get_globals() assuming that __cxa_get_globals() has already
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 * been called at least once by this thread.
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 */
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__cxa_eh_globals *__cxa_get_globals_fast(void);
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std::type_info * __cxa_current_exception_type();
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/**
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 * Throws an exception returned by __cxa_current_primary_exception().  This
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 * exception may have been caught in another thread.
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 */
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void __cxa_rethrow_primary_exception(void* thrown_exception);
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/**
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 * Returns the current exception in a form that can be stored in an
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 * exception_ptr object and then rethrown by a call to
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 * __cxa_rethrow_primary_exception().
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 */
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void *__cxa_current_primary_exception(void);
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/**
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 * Increments the reference count of an exception.  Called when an
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 * exception_ptr is copied.
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 */
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void __cxa_increment_exception_refcount(void* thrown_exception);
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/**
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 * Decrements the reference count of an exception.  Called when an
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 * exception_ptr is deleted.
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 */
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void __cxa_decrement_exception_refcount(void* thrown_exception);
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/**
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 * Demangles a C++ symbol or type name.  The buffer, if non-NULL, must be
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 * allocated with malloc() and must be *n bytes or more long.  This function
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 * may call realloc() on the value pointed to by buf, and will return the
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 * length of the string via *n.
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 *
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 * The value pointed to by status is set to one of the following:
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 *
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 * 0: success
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 * -1: memory allocation failure
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 * -2: invalid mangled name
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 * -3: invalid arguments
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 */
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char* __cxa_demangle(const char* mangled_name,
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                     char* buf,
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                     size_t* n,
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                     int* status);
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#ifdef __cplusplus
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} // extern "C"
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} // namespace
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namespace abi = __cxxabiv1;
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#endif /* __cplusplus */
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#endif /* __CXXABI_H_ */