LI71448: Compiler error 1540-1109 incorrectly generated

Latest updates for XL C/C++ Advanced Edition V8 for Linux
May 2009 Updates for XL C/C++ Advanced Edition V8 for Linux

APAR status

• Closed as program error.

Error description

• Compiler is incorrectly resolving the names in the default
  argument at the point of the definition of that default
  argument, when it should be resolved at the point of
  instantiation since the default argument is
  template-dependent.
  
  TESTCASE:
  --------
  template<class T> class Traits;
  
  class XXX {};
  
  template<>
  struct Traits<XXX> {
    enum {classRevision = 0};
  };
  
  template <class T1, class T2, int I =
  (int)Traits<T2>::classRevision> struct A { };
  template <int I, class T2> struct A<short, T2, I> { };
  
  class YYY{};
  template<>
  struct Traits<YYY>{
     enum {classRevision = 1};
  };
  
  
  A<double, XXX> x1;
  A<short, XXX> x2;
  A<double, YYY> x3;
  A<short, YYY> x4;
  
  ACTUAL OUTPUT:
  -------------
  "t10.cpp", line 10.44: 1540-1109 (S) The use of undefined class
  "Traits<YYY>" is not valid.
  "t10.cpp", line 10.44: 1540-1109 (S) The use of undefined class
  "Traits<YYY>" is not valid.
  

Local fix

• ove the class referenced in the message so that it
                      is before the default argument causing the
  message.
  

Problem summary

• USER AFFECTED:
  Users of template-dependent default template
  arguments.
  
  PROBLEM DESCRIPTION:
  We were incorrectly resolving the names in
  the default argument at the point of the
  definition of that default argument,
  when it should be resolved at the
  point of instantiation since the default
  argument is
  template-dependent.
  
  EXPECTED ERROR:
  User would see an error indicating an
  invalid use of
  an undefined or incomplete class at the
  point of definition
  finition of the invalid default argument.
  

Problem conclusion

• We now correctly resolve names in dependent
  template parameters at the point of instantiation.
  

Temporary fix

Comments

APAR Information

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

  IY78557

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

Fix information

• Fixed component name

  XLC/C++ SLES9

• Fixed component ID

  5724M1600

Applicable component levels

• R800 PSN

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