PI58813: C++11 AUTO USAGE WITH PRIVATE NESTED CLASSES

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Usage of the C++11 auto feature to deduce the type of a private
  nested class is emitting an error stating that the member can
  not be accessed.
  
  
  
     === TEST CASE ===
  
  class enclose
  {
      class nested
      {
      public:
          void use() {}
      };
  
      nested _n;
  
   public:
      enclose()
      {
          _n = nested();
      }
  
      nested& getref()     { return _n; }
      nested* getpointer() { return &_n; }
      nested  getval()     { return _n; }
  };
  
  int main()
  {
      enclose e = enclose();
  
      e.getref().use();
      e.getpointer()->use();
      e.getval().use();
  
      auto& n2 = e.getref();       // comment out
      n2.use();                    // to get next error
  
      auto* n3 = e.getpointer();   // comment out
      n3->use();                   // to get next error
  
      auto n4 = e.getval();
      n4.use();
  }
  
  
  
  > xlC test.cpp -qlanglvl=extended0x
  "./test.cpp", line 30.11: CCN5300 (S) The "private" member
  "class enclose::nested" cannot be accessed.
  CCN0793(I) Compilation failed for file ./test.cpp.  Object file
  not created.
  >
  
  > xlC test.cpp -qlanglvl=extended0x
  "./test.cpp", line 33.11: CCN5300 (S) The "private" member
  "class enclose::nested" cannot be accessed.
  CCN0793(I) Compilation failed for file ./test.cpp.  Object file
  not created.
  >
  
  > xlC test.cpp -qlanglvl=extended0x
  "./test.cpp", line 36.10: CCN5300 (S) The "private" member
  "class enclose::nested" cannot be accessed.
  CCN0793(I) Compilation failed for file ./test.cpp.  Object file
  not created.
  >
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: zOS XLC users of c++ 2011 auto type.         *
  ****************************************************************
  * PROBLEM DESCRIPTION: Access to a private class member from   *
  *                      an auto type that does not name the     *
  *                      private member should be permitted,     *
  *                      the compiler generates a private        *
  *                      access violation error.                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  .
  

Problem conclusion

• Apply provided service.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  PI51318

• APAR is sysrouted TO one or more of the following:

Modules/Macros

•    CCNEPP
  

Fix information

• Fixed component name

  C/C++ FOR MVS

• Fixed component ID

  56551210A

Applicable component levels

• R7A0 PSY UI36029

     UP16/04/26 P F604

Fix is available

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