string 析构崩溃 assign

• 崩溃

(gdb) bt
#0  0x00007f5a4eb24418 in _int_free () from /lib64/libc.so.6
#1  0x00007f5a4f440c03 in std::basic_string<char, std::char_traits<char>, std::allocator<char> >::~basic_string() () from /lib64/libstdc++.so.6
#2  0x000000000042ad93 in CEndpoint::FileMD5 (this=0x7f59d80010c0, event=..., scan_list=std::list = {...}, info=...) at ../Endpoint.cpp:322

...

#7  0x00007f5a50eeae25 in start_thread () from /lib64/libpthread.so.0
#8  0x00007f5a4eba034d in clone () from /lib64/libc.so.6
(gdb) f 2
#2  0x000000000042ad93 in CEndpoint::FileMD5 (this=0x7f59d80010c0, event=..., scan_list=std::list = {...}, info=...) at ../Endpoint.cpp:322
(gdb) p uploadJSON
$1 = "{\"FilePath\":\"c:\\\\windows\\\\ey87mb9scd\\\\x86\\\\secopatcher.dll\",\"MD5\":\"e0f0683bb8cfd4413eccd777034e6a20\"}"

• 代码

析构中报错

/**
       *  @brief  Destroy the string instance.
       */
      ~basic_string() _GLIBCXX_NOEXCEPT
      { _M_rep()->_M_dispose(this->get_allocator()); }

_M_dispose

void
  _M_dispose(const _Alloc& __a)
  {
#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
    if (__builtin_expect(this != &_S_empty_rep(), false))
#endif
      {
        // Be race-detector-friendly.  For more info see bits/c++config.
        _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount);
        if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
               -1) <= 0)
    {
      _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount);
      _M_destroy(__a);
    }
      }
  }  // XXX MT

_M_destroy 在basic_string.tcc定义

template<typename _CharT, typename _Traits, typename _Alloc>
    void
    basic_string<_CharT, _Traits, _Alloc>::_Rep::
    _M_destroy(const _Alloc& __a) throw ()
    {
      const size_type __size = sizeof(_Rep_base) +
                           (this->_M_capacity + 1) * sizeof(_CharT);
      _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
    }

_Alloc deallocate 释放内存

/**
   * @brief  Uniform interface to all allocator types.
   * @ingroup allocators
  */
  template<typename _Alloc>
    struct allocator_traits
    {
      /// The allocator type
      typedef _Alloc allocator_type;
      /// The allocated type
      typedef typename _Alloc::value_type value_type;
 
     /**
       *  @brief  Deallocate memory.
       *  @param  __a  An allocator.
       *  @param  __p  Pointer to the memory to deallocate.
       *  @param  __n  The number of objects space was allocated for.
       *
       *  Calls <tt> a.deallocate(p, n) </tt>
      */
      static void deallocate(_Alloc& __a, pointer __p, size_type __n)
      { __a.deallocate(__p, __n); }

 
      ...
    
    }

代码中是用assign来 str.assign(str2)，str2 是通过rapidjson GetString()获得，    basic_string.h头文件内容中声明basic_string& assign(const basic_string& __str);

#include <ext/atomicity.h>
    #include <debug/debug.h>
    #if __cplusplus >= 201103L
        #include <initializer_list>
    #endif

     /**
       *  @brief  Set value to contents of another string.
       *  @param  __str  Source string to use.
       *  @return  Reference to this string.
       */
      basic_string&
      assign(const basic_string& __str);

basic_string.h 中 #include <debug/debug.h>， 在debug.h中找到assign定义

basic_string&
    assign(const basic_string& __x)
    {
      _Base::assign(__x);
      this->_M_invalidate_all();
      return *this;
    }

str析构的时候崩溃