IZ40765: TEMPLATE OMISSION PROBLEM

January 2009 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
April 2009 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
July 2009 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
November 2010 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
March 2011 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
July 2011 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
December 2011 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
March 2012 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
January 2010 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
May 2010 PTF for XL C/C++ Enterprise Edition for AIX, V9.0
August 2010 PTF for XL C/C++ Enterprise Edition for AIX, V9.0

APAR status

• Closed as program error.

Error description

• xlC is not appropriately omiting trailing template arguments as
  detailed in C++, ISO/IEC 14882:2003, 14.8.1 Explicit template
  argument specification.
  
  ================================================================
  
  struct FF
  {
      typedef double result_type;
  };
  
  struct target;
  
  void doreply( target*, double&);
  
  template<class F, class T>
  void send_request(void (*reply)(T* t, typename F::result_type&
  r));
  
  void foo()
  {
      send_request<FF>(&doreply);
  }
  

Local fix

• If all the template parameters are explicitly specified, the
  compiler will not go into argument deduction.
  ===============================================================
  Explicitely provide the template arguments:
  
  send_request<FF, target, memo>(arg,&doreply,m);
  

Problem summary

• The problem appears during argument deduction when a template
  parameter is in a non-deduced context.
  
  The compiler was attempting to deduce a parameter from a
  non-deduced context instead of using the explicitly specified
  argument
  

Problem conclusion

• Argument deduction now skips the non-deduced context and uses
  the explicit argument
  

Temporary fix

Comments

APAR Information

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

  IZ35151

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

Fix information

• Fixed component name

  XLC C++ AIX

• Fixed component ID

  5724S7100

Applicable component levels