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  1. // ABI Support -*- C++ -*-
  2.  
  3. // Copyright (C) 2000-2013 Free Software Foundation, Inc.
  4. //
  5. // This file is part of GCC.
  6. //
  7. // GCC is free software; you can redistribute it and/or modify
  8. // it under the terms of the GNU General Public License as published by
  9. // the Free Software Foundation; either version 3, or (at your option)
  10. // any later version.
  11. //
  12. // GCC is distributed in the hope that it will be useful,
  13. // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14. // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15. // GNU General Public License for more details.
  16. //
  17. // Under Section 7 of GPL version 3, you are granted additional
  18. // permissions described in the GCC Runtime Library Exception, version
  19. // 3.1, as published by the Free Software Foundation.
  20.  
  21. // You should have received a copy of the GNU General Public License and
  22. // a copy of the GCC Runtime Library Exception along with this program;
  23. // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24. // <http://www.gnu.org/licenses/>.
  25.  
  26. // Written by Nathan Sidwell, Codesourcery LLC, <nathan@codesourcery.com>
  27.  
  28. /* This file declares the new abi entry points into the runtime. It is not
  29.    normally necessary for user programs to include this header, or use the
  30.    entry points directly. However, this header is available should that be
  31.    needed.
  32.  
  33.    Some of the entry points are intended for both C and C++, thus this header
  34.    is includable from both C and C++. Though the C++ specific parts are not
  35.    available in C, naturally enough.  */
  36.  
  37. /** @file cxxabi.h
  38.  *  The header provides an interface to the C++ ABI.
  39.  */
  40.  
  41. #ifndef _CXXABI_H
  42. #define _CXXABI_H 1
  43.  
  44. #pragma GCC system_header
  45.  
  46. #pragma GCC visibility push(default)
  47.  
  48. #include <stddef.h>
  49. #include <bits/c++config.h>
  50. #include <bits/cxxabi_tweaks.h>
  51. #include <bits/cxxabi_forced.h>
  52.  
  53. #ifndef _GLIBCXX_CDTOR_CALLABI
  54. #define _GLIBCXX_CDTOR_CALLABI
  55. #endif
  56.  
  57. #ifdef __cplusplus
  58. namespace __cxxabiv1
  59. {
  60.   extern "C"
  61.   {
  62. #endif
  63.  
  64.   typedef __cxa_cdtor_return_type (*__cxa_cdtor_type)(void *);
  65.  
  66.   // Allocate array.
  67.   void*
  68.   __cxa_vec_new(size_t __element_count, size_t __element_size,
  69.                 size_t __padding_size, __cxa_cdtor_type __constructor,
  70.                 __cxa_cdtor_type __destructor);
  71.  
  72.   void*
  73.   __cxa_vec_new2(size_t __element_count, size_t __element_size,
  74.                  size_t __padding_size, __cxa_cdtor_type __constructor,
  75.                  __cxa_cdtor_type __destructor, void *(*__alloc) (size_t),
  76.                  void (*__dealloc) (void*));
  77.  
  78.   void*
  79.   __cxa_vec_new3(size_t __element_count, size_t __element_size,
  80.                  size_t __padding_size, __cxa_cdtor_type __constructor,
  81.                  __cxa_cdtor_type __destructor, void *(*__alloc) (size_t),
  82.                  void (*__dealloc) (void*, size_t));
  83.  
  84.   // Construct array.
  85.   __cxa_vec_ctor_return_type
  86.   __cxa_vec_ctor(void* __array_address, size_t __element_count,
  87.                  size_t __element_size, __cxa_cdtor_type __constructor,
  88.                  __cxa_cdtor_type __destructor);
  89.  
  90.   __cxa_vec_ctor_return_type
  91.   __cxa_vec_cctor(void* __dest_array, void* __src_array,
  92.                   size_t __element_count, size_t __element_size,
  93.                   __cxa_cdtor_return_type (*__constructor) (void*, void*),
  94.                   __cxa_cdtor_type __destructor);
  95.  
  96.   // Destruct array.
  97.   void
  98.   __cxa_vec_dtor(void* __array_address, size_t __element_count,
  99.                  size_t __element_size, __cxa_cdtor_type __destructor);
  100.  
  101.   void
  102.   __cxa_vec_cleanup(void* __array_address, size_t __element_count, size_t __s,
  103.                     __cxa_cdtor_type __destructor) _GLIBCXX_NOTHROW;
  104.  
  105.   // Destruct and release array.
  106.   void
  107.   __cxa_vec_delete(void* __array_address, size_t __element_size,
  108.                    size_t __padding_size, __cxa_cdtor_type __destructor);
  109.  
  110.   void
  111.   __cxa_vec_delete2(void* __array_address, size_t __element_size,
  112.                     size_t __padding_size, __cxa_cdtor_type __destructor,
  113.                     void (*__dealloc) (void*));
  114.  
  115.   void
  116.   __cxa_vec_delete3(void* __array_address, size_t __element_size,
  117.                     size_t __padding_size, __cxa_cdtor_type __destructor,
  118.                     void (*__dealloc) (void*, size_t));
  119.  
  120.   int
  121.   __cxa_guard_acquire(__guard*);
  122.  
  123.   void
  124.   __cxa_guard_release(__guard*) _GLIBCXX_NOTHROW;
  125.  
  126.   void
  127.   __cxa_guard_abort(__guard*) _GLIBCXX_NOTHROW;
  128.  
  129.   // DSO destruction.
  130.   int
  131.   __cxa_atexit(void (*)(void*), void*, void*) _GLIBCXX_NOTHROW;
  132.  
  133.   int
  134.   __cxa_finalize(void*);
  135.  
  136.   // TLS destruction.
  137.   int
  138.   __cxa_thread_atexit(void (*)(void*), void*, void *) _GLIBCXX_NOTHROW;
  139.  
  140.   // Pure virtual functions.
  141.   void
  142.   __cxa_pure_virtual(void) __attribute__ ((__noreturn__));
  143.  
  144.   void
  145.   __cxa_deleted_virtual(void) __attribute__ ((__noreturn__));
  146.  
  147.   // Exception handling auxillary.
  148.   void
  149.   __cxa_bad_cast() __attribute__((__noreturn__));
  150.  
  151.   void
  152.   __cxa_bad_typeid() __attribute__((__noreturn__));
  153.  
  154.  
  155.   /**
  156.    *  @brief Demangling routine.
  157.    *  ABI-mandated entry point in the C++ runtime library for demangling.
  158.    *
  159.    *  @param __mangled_name A NUL-terminated character string
  160.    *  containing the name to be demangled.
  161.    *
  162.    *  @param __output_buffer A region of memory, allocated with
  163.    *  malloc, of @a *__length bytes, into which the demangled name is
  164.    *  stored.  If @a __output_buffer is not long enough, it is
  165.    *  expanded using realloc.  @a __output_buffer may instead be NULL;
  166.    *  in that case, the demangled name is placed in a region of memory
  167.    *  allocated with malloc.
  168.    *
  169.    *  @param __length If @a __length is non-NULL, the length of the
  170.    *  buffer containing the demangled name is placed in @a *__length.
  171.    *
  172.    *  @param __status @a *__status is set to one of the following values:
  173.    *   0: The demangling operation succeeded.
  174.    *  -1: A memory allocation failure occurred.
  175.    *  -2: @a mangled_name is not a valid name under the C++ ABI mangling rules.
  176.    *  -3: One of the arguments is invalid.
  177.    *
  178.    *  @return A pointer to the start of the NUL-terminated demangled
  179.    *  name, or NULL if the demangling fails.  The caller is
  180.    *  responsible for deallocating this memory using @c free.
  181.    *
  182.    *  The demangling is performed using the C++ ABI mangling rules,
  183.    *  with GNU extensions. For example, this function is used in
  184.    *  __gnu_cxx::__verbose_terminate_handler.
  185.    *
  186.    *  See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt12ch39.html
  187.    *  for other examples of use.
  188.    *
  189.    *  @note The same demangling functionality is available via
  190.    *  libiberty (@c <libiberty/demangle.h> and @c libiberty.a) in GCC
  191.    *  3.1 and later, but that requires explicit installation (@c
  192.    *  --enable-install-libiberty) and uses a different API, although
  193.    *  the ABI is unchanged.
  194.    */
  195.   char*
  196.   __cxa_demangle(const char* __mangled_name, char* __output_buffer,
  197.                  size_t* __length, int* __status);
  198.  
  199. #ifdef __cplusplus
  200.   }
  201. } // namespace __cxxabiv1
  202. #endif
  203.  
  204. #ifdef __cplusplus
  205.  
  206. #include <typeinfo>
  207.  
  208. namespace __cxxabiv1
  209. {
  210.   // Type information for int, float etc.
  211.   class __fundamental_type_info : public std::type_info
  212.   {
  213.   public:
  214.     explicit
  215.     __fundamental_type_info(const char* __n) : std::type_info(__n) { }
  216.  
  217.     virtual
  218.     ~__fundamental_type_info();
  219.   };
  220.  
  221.   // Type information for array objects.
  222.   class __array_type_info : public std::type_info
  223.   {
  224.   public:
  225.     explicit
  226.     __array_type_info(const char* __n) : std::type_info(__n) { }
  227.  
  228.     virtual
  229.     ~__array_type_info();
  230.   };
  231.  
  232.   // Type information for functions (both member and non-member).
  233.   class __function_type_info : public std::type_info
  234.   {
  235.   public:
  236.     explicit
  237.     __function_type_info(const char* __n) : std::type_info(__n) { }
  238.  
  239.     virtual
  240.     ~__function_type_info();
  241.  
  242.   protected:
  243.     // Implementation defined member function.
  244.     virtual bool
  245.     __is_function_p() const;
  246.   };
  247.  
  248.   // Type information for enumerations.
  249.   class __enum_type_info : public std::type_info
  250.   {
  251.   public:
  252.     explicit
  253.     __enum_type_info(const char* __n) : std::type_info(__n) { }
  254.  
  255.     virtual
  256.     ~__enum_type_info();
  257.   };
  258.  
  259.   // Common type information for simple pointers and pointers to member.
  260.   class __pbase_type_info : public std::type_info
  261.   {
  262.   public:
  263.     unsigned int                __flags; // Qualification of the target object.
  264.     const std::type_info*       __pointee; // Type of pointed to object.
  265.  
  266.     explicit
  267.     __pbase_type_info(const char* __n, int __quals,
  268.                       const std::type_info* __type)
  269.     : std::type_info(__n), __flags(__quals), __pointee(__type)
  270.     { }
  271.  
  272.     virtual
  273.     ~__pbase_type_info();
  274.  
  275.     // Implementation defined type.
  276.     enum __masks
  277.       {
  278.         __const_mask = 0x1,
  279.         __volatile_mask = 0x2,
  280.         __restrict_mask = 0x4,
  281.         __incomplete_mask = 0x8,
  282.         __incomplete_class_mask = 0x10
  283.       };
  284.  
  285.   protected:
  286.     __pbase_type_info(const __pbase_type_info&);
  287.  
  288.     __pbase_type_info&
  289.     operator=(const __pbase_type_info&);
  290.  
  291.     // Implementation defined member functions.
  292.     virtual bool
  293.     __do_catch(const std::type_info* __thr_type, void** __thr_obj,
  294.                unsigned int __outer) const;
  295.  
  296.     inline virtual bool
  297.     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
  298.                     unsigned __outer) const;
  299.   };
  300.  
  301.   // Type information for simple pointers.
  302.   class __pointer_type_info : public __pbase_type_info
  303.   {
  304.   public:
  305.     explicit
  306.     __pointer_type_info(const char* __n, int __quals,
  307.                         const std::type_info* __type)
  308.     : __pbase_type_info (__n, __quals, __type) { }
  309.  
  310.  
  311.     virtual
  312.     ~__pointer_type_info();
  313.  
  314.   protected:
  315.     // Implementation defined member functions.
  316.     virtual bool
  317.     __is_pointer_p() const;
  318.  
  319.     virtual bool
  320.     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
  321.                     unsigned __outer) const;
  322.   };
  323.  
  324.   class __class_type_info;
  325.  
  326.   // Type information for a pointer to member variable.
  327.   class __pointer_to_member_type_info : public __pbase_type_info
  328.   {
  329.   public:
  330.     __class_type_info* __context;   // Class of the member.
  331.  
  332.     explicit
  333.     __pointer_to_member_type_info(const char* __n, int __quals,
  334.                                   const std::type_info* __type,
  335.                                   __class_type_info* __klass)
  336.     : __pbase_type_info(__n, __quals, __type), __context(__klass) { }
  337.  
  338.     virtual
  339.     ~__pointer_to_member_type_info();
  340.  
  341.   protected:
  342.     __pointer_to_member_type_info(const __pointer_to_member_type_info&);
  343.  
  344.     __pointer_to_member_type_info&
  345.     operator=(const __pointer_to_member_type_info&);
  346.  
  347.     // Implementation defined member function.
  348.     virtual bool
  349.     __pointer_catch(const __pbase_type_info* __thr_type, void** __thr_obj,
  350.                     unsigned __outer) const;
  351.   };
  352.  
  353.   // Helper class for __vmi_class_type.
  354.   class __base_class_type_info
  355.   {
  356.   public:
  357.     const __class_type_info*    __base_type;  // Base class type.
  358. #ifdef _GLIBCXX_LLP64
  359.     long long                   __offset_flags;  // Offset and info.
  360. #else
  361.     long                        __offset_flags;  // Offset and info.
  362. #endif
  363.  
  364.     enum __offset_flags_masks
  365.       {
  366.         __virtual_mask = 0x1,
  367.         __public_mask = 0x2,
  368.         __hwm_bit = 2,
  369.         __offset_shift = 8          // Bits to shift offset.
  370.       };
  371.  
  372.     // Implementation defined member functions.
  373.     bool
  374.     __is_virtual_p() const
  375.     { return __offset_flags & __virtual_mask; }
  376.  
  377.     bool
  378.     __is_public_p() const
  379.     { return __offset_flags & __public_mask; }
  380.  
  381.     ptrdiff_t
  382.     __offset() const
  383.     {
  384.       // This shift, being of a signed type, is implementation
  385.       // defined. GCC implements such shifts as arithmetic, which is
  386.       // what we want.
  387.       return static_cast<ptrdiff_t>(__offset_flags) >> __offset_shift;
  388.     }
  389.   };
  390.  
  391.   // Type information for a class.
  392.   class __class_type_info : public std::type_info
  393.   {
  394.   public:
  395.     explicit
  396.     __class_type_info (const char *__n) : type_info(__n) { }
  397.  
  398.     virtual
  399.     ~__class_type_info ();
  400.  
  401.     // Implementation defined types.
  402.     // The type sub_kind tells us about how a base object is contained
  403.     // within a derived object. We often do this lazily, hence the
  404.     // UNKNOWN value. At other times we may use NOT_CONTAINED to mean
  405.     // not publicly contained.
  406.     enum __sub_kind
  407.       {
  408.         // We have no idea.
  409.         __unknown = 0,
  410.  
  411.         // Not contained within us (in some circumstances this might
  412.         // mean not contained publicly)
  413.         __not_contained,
  414.  
  415.         // Contained ambiguously.
  416.         __contained_ambig,
  417.  
  418.         // Via a virtual path.
  419.         __contained_virtual_mask = __base_class_type_info::__virtual_mask,
  420.  
  421.         // Via a public path.
  422.         __contained_public_mask = __base_class_type_info::__public_mask,
  423.  
  424.         // Contained within us.
  425.         __contained_mask = 1 << __base_class_type_info::__hwm_bit,
  426.  
  427.         __contained_private = __contained_mask,
  428.         __contained_public = __contained_mask | __contained_public_mask
  429.       };
  430.  
  431.     struct __upcast_result;
  432.     struct __dyncast_result;
  433.  
  434.   protected:
  435.     // Implementation defined member functions.
  436.     virtual bool
  437.     __do_upcast(const __class_type_info* __dst_type, void**__obj_ptr) const;
  438.  
  439.     virtual bool
  440.     __do_catch(const type_info* __thr_type, void** __thr_obj,
  441.                unsigned __outer) const;
  442.  
  443.   public:
  444.     // Helper for upcast. See if DST is us, or one of our bases.
  445.     // Return false if not found, true if found.
  446.     virtual bool
  447.     __do_upcast(const __class_type_info* __dst, const void* __obj,
  448.                 __upcast_result& __restrict __result) const;
  449.  
  450.     // Indicate whether SRC_PTR of type SRC_TYPE is contained publicly
  451.     // within OBJ_PTR. OBJ_PTR points to a base object of our type,
  452.     // which is the destination type. SRC2DST indicates how SRC
  453.     // objects might be contained within this type.  If SRC_PTR is one
  454.     // of our SRC_TYPE bases, indicate the virtuality. Returns
  455.     // not_contained for non containment or private containment.
  456.     inline __sub_kind
  457.     __find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
  458.                       const __class_type_info* __src_type,
  459.                       const void* __src_ptr) const;
  460.  
  461.     // Helper for dynamic cast. ACCESS_PATH gives the access from the
  462.     // most derived object to this base. DST_TYPE indicates the
  463.     // desired type we want. OBJ_PTR points to a base of our type
  464.     // within the complete object. SRC_TYPE indicates the static type
  465.     // started from and SRC_PTR points to that base within the most
  466.     // derived object. Fill in RESULT with what we find. Return true
  467.     // if we have located an ambiguous match.
  468.     virtual bool
  469.     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
  470.                  const __class_type_info* __dst_type, const void* __obj_ptr,
  471.                  const __class_type_info* __src_type, const void* __src_ptr,
  472.                  __dyncast_result& __result) const;
  473.  
  474.     // Helper for find_public_subobj. SRC2DST indicates how SRC_TYPE
  475.     // bases are inherited by the type started from -- which is not
  476.     // necessarily the current type. The current type will be a base
  477.     // of the destination type.  OBJ_PTR points to the current base.
  478.     virtual __sub_kind
  479.     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
  480.                          const __class_type_info* __src_type,
  481.                          const void* __src_ptr) const;
  482.   };
  483.  
  484.   // Type information for a class with a single non-virtual base.
  485.   class __si_class_type_info : public __class_type_info
  486.   {
  487.   public:
  488.     const __class_type_info* __base_type;
  489.  
  490.     explicit
  491.     __si_class_type_info(const char *__n, const __class_type_info *__base)
  492.     : __class_type_info(__n), __base_type(__base) { }
  493.  
  494.     virtual
  495.     ~__si_class_type_info();
  496.  
  497.   protected:
  498.     __si_class_type_info(const __si_class_type_info&);
  499.  
  500.     __si_class_type_info&
  501.     operator=(const __si_class_type_info&);
  502.  
  503.     // Implementation defined member functions.
  504.     virtual bool
  505.     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
  506.                  const __class_type_info* __dst_type, const void* __obj_ptr,
  507.                  const __class_type_info* __src_type, const void* __src_ptr,
  508.                  __dyncast_result& __result) const;
  509.  
  510.     virtual __sub_kind
  511.     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
  512.                          const __class_type_info* __src_type,
  513.                          const void* __sub_ptr) const;
  514.  
  515.     virtual bool
  516.     __do_upcast(const __class_type_info*__dst, const void*__obj,
  517.                 __upcast_result& __restrict __result) const;
  518.   };
  519.  
  520.   // Type information for a class with multiple and/or virtual bases.
  521.   class __vmi_class_type_info : public __class_type_info
  522.   {
  523.   public:
  524.     unsigned int                __flags;  // Details about the class hierarchy.
  525.     unsigned int                __base_count;  // Number of direct bases.
  526.  
  527.     // The array of bases uses the trailing array struct hack so this
  528.     // class is not constructable with a normal constructor. It is
  529.     // internally generated by the compiler.
  530.     __base_class_type_info      __base_info[1];  // Array of bases.
  531.  
  532.     explicit
  533.     __vmi_class_type_info(const char* __n, int ___flags)
  534.     : __class_type_info(__n), __flags(___flags), __base_count(0) { }
  535.  
  536.     virtual
  537.     ~__vmi_class_type_info();
  538.  
  539.     // Implementation defined types.
  540.     enum __flags_masks
  541.       {
  542.         __non_diamond_repeat_mask = 0x1, // Distinct instance of repeated base.
  543.         __diamond_shaped_mask = 0x2, // Diamond shaped multiple inheritance.
  544.         __flags_unknown_mask = 0x10
  545.       };
  546.  
  547.   protected:
  548.     // Implementation defined member functions.
  549.     virtual bool
  550.     __do_dyncast(ptrdiff_t __src2dst, __sub_kind __access_path,
  551.                  const __class_type_info* __dst_type, const void* __obj_ptr,
  552.                  const __class_type_info* __src_type, const void* __src_ptr,
  553.                  __dyncast_result& __result) const;
  554.  
  555.     virtual __sub_kind
  556.     __do_find_public_src(ptrdiff_t __src2dst, const void* __obj_ptr,
  557.                          const __class_type_info* __src_type,
  558.                          const void* __src_ptr) const;
  559.  
  560.     virtual bool
  561.     __do_upcast(const __class_type_info* __dst, const void* __obj,
  562.                 __upcast_result& __restrict __result) const;
  563.   };
  564.  
  565.   // Exception handling forward declarations.
  566.   struct __cxa_exception;
  567.   struct __cxa_refcounted_exception;
  568.   struct __cxa_dependent_exception;
  569.   struct __cxa_eh_globals;
  570.  
  571.   extern "C"
  572.   {
  573.   // Dynamic cast runtime.
  574.  
  575.   // src2dst has the following possible values
  576.   //  >-1: src_type is a unique public non-virtual base of dst_type
  577.   //       dst_ptr + src2dst == src_ptr
  578.   //   -1: unspecified relationship
  579.   //   -2: src_type is not a public base of dst_type
  580.   //   -3: src_type is a multiple public non-virtual base of dst_type
  581.   void*
  582.   __dynamic_cast(const void* __src_ptr, // Starting object.
  583.                  const __class_type_info* __src_type, // Static type of object.
  584.                  const __class_type_info* __dst_type, // Desired target type.
  585.                  ptrdiff_t __src2dst); // How src and dst are related.
  586.  
  587.  
  588.   // Exception handling runtime.
  589.  
  590.   // The __cxa_eh_globals for the current thread can be obtained by using
  591.   // either of the following functions.  The "fast" version assumes at least
  592.   // one prior call of __cxa_get_globals has been made from the current
  593.   // thread, so no initialization is necessary.
  594.   __cxa_eh_globals*
  595.   __cxa_get_globals() _GLIBCXX_NOTHROW __attribute__ ((__const__));
  596.  
  597.   __cxa_eh_globals*
  598.   __cxa_get_globals_fast() _GLIBCXX_NOTHROW __attribute__ ((__const__));
  599.  
  600.   // Allocate memory for the primary exception plus the thrown object.
  601.   void*
  602.   __cxa_allocate_exception(size_t) _GLIBCXX_NOTHROW;
  603.  
  604.   // Free the space allocated for the primary exception.
  605.   void
  606.   __cxa_free_exception(void*) _GLIBCXX_NOTHROW;
  607.  
  608.   // Throw the exception.
  609.   void
  610.   __cxa_throw(void*, std::type_info*, void (_GLIBCXX_CDTOR_CALLABI *) (void *))
  611.   __attribute__((__noreturn__));
  612.  
  613.   // Used to implement exception handlers.
  614.   void*
  615.   __cxa_get_exception_ptr(void*) _GLIBCXX_NOTHROW __attribute__ ((__pure__));
  616.  
  617.   void*
  618.   __cxa_begin_catch(void*) _GLIBCXX_NOTHROW;
  619.  
  620.   void
  621.   __cxa_end_catch();
  622.  
  623.   void
  624.   __cxa_rethrow() __attribute__((__noreturn__));
  625.  
  626.   // Returns the type_info for the currently handled exception [15.3/8], or
  627.   // null if there is none.
  628.   std::type_info*
  629.   __cxa_current_exception_type() _GLIBCXX_NOTHROW __attribute__ ((__pure__));
  630.  
  631.   // GNU Extensions.
  632.  
  633.   // Allocate memory for a dependent exception.
  634.   __cxa_dependent_exception*
  635.   __cxa_allocate_dependent_exception() _GLIBCXX_NOTHROW;
  636.  
  637.   // Free the space allocated for the dependent exception.
  638.   void
  639.   __cxa_free_dependent_exception(__cxa_dependent_exception*) _GLIBCXX_NOTHROW;
  640.  
  641.   } // extern "C"
  642.  
  643.   // A magic placeholder class that can be caught by reference
  644.   // to recognize foreign exceptions.
  645.   class __foreign_exception
  646.   {
  647.     virtual ~__foreign_exception() throw();
  648.     virtual void __pure_dummy() = 0; // prevent catch by value
  649.   };
  650.  
  651. } // namespace __cxxabiv1
  652.  
  653. /** @namespace abi
  654.  *  @brief The cross-vendor C++ Application Binary Interface. A
  655.  *  namespace alias to __cxxabiv1, but user programs should use the
  656.  *  alias 'abi'.
  657.  *
  658.  *  A brief overview of an ABI is given in the libstdc++ FAQ, question
  659.  *  5.8 (you may have a copy of the FAQ locally, or you can view the online
  660.  *  version at http://gcc.gnu.org/onlinedocs/libstdc++/faq.html#5_8 ).
  661.  *
  662.  *  GCC subscribes to a cross-vendor ABI for C++, sometimes
  663.  *  called the IA64 ABI because it happens to be the native ABI for that
  664.  *  platform.  It is summarized at http://www.codesourcery.com/cxx-abi/
  665.  *  along with the current specification.
  666.  *
  667.  *  For users of GCC greater than or equal to 3.x, entry points are
  668.  *  available in <cxxabi.h>, which notes, <em>'It is not normally
  669.  *  necessary for user programs to include this header, or use the
  670.  *  entry points directly.  However, this header is available should
  671.  *  that be needed.'</em>
  672. */
  673. namespace abi = __cxxabiv1;
  674.  
  675. namespace __gnu_cxx
  676. {
  677.   /**
  678.    *  @brief Exception thrown by __cxa_guard_acquire.
  679.    *  @ingroup exceptions
  680.    *
  681.    *  6.7[stmt.dcl]/4: If control re-enters the declaration (recursively)
  682.    *  while the object is being initialized, the behavior is undefined.
  683.    *
  684.    *  Since we already have a library function to handle locking, we might
  685.    *  as well check for this situation and throw an exception.
  686.    *  We use the second byte of the guard variable to remember that we're
  687.    *  in the middle of an initialization.
  688.    */
  689.   class recursive_init_error: public std::exception
  690.   {
  691.   public:
  692.     recursive_init_error() throw() { }
  693.     virtual ~recursive_init_error() throw ();
  694.   };
  695. }
  696. #endif // __cplusplus
  697.  
  698. #pragma GCC visibility pop
  699.  
  700. #endif // __CXXABI_H
  701.