Wrong name in error messages (egcs-19990907)

[Jeroen]

Hi, here are some more oddities with gcc when it encounters an error :


template <typename T>
class A
{
public:
#ifdef F1
  A() {}
#endif
};

template <typename T>
class B
{
public:
  template <class C> void f(int p, C& c)
    {
      f(p,c); 
    }

  void f(int p)
    {
      A<T> c;
      f(p,c); // this works

#if F2 == 1
      f(p,  A<T>()); // line 25: doesn't work
#endif
#if F2 == 2
      f(p, (A<T>()));  // line 28:workaround as suggested in FAQ (Parse
Errors for simple code)
#endif
#if F2 == 3
      f(p, (0, A<T>())); // line 31:other workaround as suggested in FAQ
(Parse Errors for simple code)
#endif
    }
};

void f1()
{
  B<char> c;
  
  c.f(1);
}


// g++ -v                
// Reading specs from
/hdc1/home2/egcs/experimental/lib/gcc-lib/i686-pc-linux-gnu/2.96/specs
// gcc version 2.96 19990907 (experimental)


// 1. no problem
// -------------
//  g++ -W -Wall -c g.cpp
//  g++ -W -Wall -c g.cpp -DF1

// 2. wrong name '{}' in warning
// -----------------------------
// g++ -W -Wall -c g.cpp -DF2=1   
//  g.cpp: In method `void B<char>::f(int)':
//  g.cpp:40:   instantiated from here
//  g.cpp:25: could not convert `{}' to `A<char> &'
//  g.cpp:15: in passing argument 2 of `B<char>::f<A<char> >(int, A<char>
&)'


// why a parse error ? :
// g++ -W -Wall -c g.cpp -DF2=2
//  g.cpp: In method `void B<T>::f(int)':
//  g.cpp:28: parse error before `)'

// g++ -W -Wall -c g.cpp -DF2=3
//  g.cpp: In method `void B<char>::f(int)':
//  g.cpp:40:   instantiated from here
//  g.cpp:31: warning: left-hand operand of comma expression has no effect
//  g.cpp:31: could not convert `{}' to `A<char> &'
//  g.cpp:15: in passing argument 2 of `B<char>::f<A<char> >(int, A<char>
&)'


// 3. good name, but why can gcc not convert ?
//    --> better error message would be nice (like : lvalue required)
// (also : why 'A<T>()' and not 'A<T>' ?)
// -------------------------------------------
// g++ -W -Wall -c g.cpp -DF1 -DF2=1
//  g.cpp: In method `void B<char>::f(int)':
//  g.cpp:40:   instantiated from here
//  g.cpp:25: could not convert `A<char>()' to `A<char> &'
//  g.cpp:15: in passing argument 2 of `B<char>::f<A<char> >(int, A<char>
&)'

// why a parse error ? :
// g++ -W -Wall -c g.cpp -DF1 -DF2=2
//  g.cpp: In method `void B<T>::f(int)':
//  g.cpp:28: parse error before `)'

// g++ -W -Wall -c g.cpp -DF1 -DF2=3
//  g.cpp: In method `void B<char>::f(int)':
//  g.cpp:40:   instantiated from here
//  g.cpp:31: warning: left-hand operand of comma expression has no effect
//  g.cpp:31: could not convert `A<char>()' to `A<char> &'
//  g.cpp:15: in passing argument 2 of `B<char>::f<A<char> >(int, A<char>
&)'

--
Jeroen Dobbelaere
Software Design Engineer
Micro-Matic Research < http://www.mmr.be >