IV30906: INCORRECT TEMPLATE SIGNATURE FOR CONST TYPE

February 2013 PTF for XL C/C++ for AIX, V11.1

APAR status

• Closed as program error.

Error description

• The signature for a template function with a const type
  parameter is being generated the same as the template function
  with a non-const type parameter.  This is causing internal and
  external linkage conflicts because the same function name is
  being used for two different functions.
  
  
      ===== TEST CASE =====
  
  template<class T>
  class MyClass { };
  
  float testfunc(MyClass<float>)      { return 1; }
  float testfunc(MyClass<const float>){ return 2; }
  
  void test() {
      MyClass<float>       withfloat;
      MyClass<const float> withconstfloat;
  
      1 == testfunc(withfloat);
      2 == testfunc(withconstfloat);
  }
  
  
  line 5.7: 1540-0704 (S) The definitions of "float
  testfunc(MyClass<const float>)" and "float
  testfunc(MyClass<float>)" have the same linkage signature
  "testfunc__F7MyClassXTf_".
  

Local fix

• N/A
  

Problem summary

• PROBLEM DESCRIPTION:
  A problem with name mangling of template type parameters causes
  a compilation error.
  
  USERS AFFECTED:
  Users of templates instantiated using datatypes with
  cv-qualified names.
  

Problem conclusion

• The name mangling behaviour was corrected in the V12.1 compiler
  by default.  The fix for the V11.1 compiler is controlled via
  the option:  -qxflag=MangleCVOnTemplateTypeArgs
  

Temporary fix

Comments

APAR Information

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

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

Fix information

• Fixed component name

  XL C/C++ AIX

• Fixed component ID

  5724X1300

Applicable component levels

• RB10 PSY U858036

     UP C