problem with template parameter in g++ 4.4.1

problem with template parameter in g++ 4.4.1

[hannibal81]

I work on a library compiled with gcc4.0 and old versions. I want to insert
OpenMP directives in the source code. So I compiled the code with gcc4.4
version since openmp is recognized that from version 4.2, but I get many
errors especially at the Definiton of templates. So I want to know what is
the difference between these versions of gcc and is there a way that ensures
the porting of programs compiled with older versions to newer versions of
gcc. Here it below some of the code and the errors obtained in compilation.

ifndef _PAT_FAM
#define _PAT_FAM

#include <iostream>
#include <vector>


template<typename P, template<typename T> class ST>
class pat_fam;
template<typename P, template<typename T> class ST>
std::ostream& operator<< (std::ostream&, const pat_fam<P, ST>&);


template<typename P, template<typename T> class ST=std::vector>
class pat_fam: public ST<P*>
{
public:
typedef typename ST<P*>::iterator IT; 
typedef typename ST<P*>::const_iterator CONST_IT; 


friend std::ostream& operator<< <>(std::ostream&, const pat_fam<P, ST>&);
};

template<class P>
std::ostream& operator<< (std::ostream& ostr, const pat_fam<P, std::vector>&
pats)
{
typename pat_fam<P, std::vector>::CONST_IT it;
for(it=pats.begin(); it!=pats.end(); it++)
ostr<<*it<<std::endl;
return ostr;
}

#endif

pat_fam.h:57: erreur: type/value mismatch at argument 2 in template
parameter list for ‘template<class P, template<class T> class ST> class
pat_fam’
pat_fam.h:57: erreur: expected a template of type ‘template<class T> class
ST’, got ‘template<class _Tp, class _Alloc> class std::vector’
pat_fam.h: In function ‘std::ostream& operator<<(std::ostream&, const
int&)’:
pat_fam.h:59: erreur: type/value mismatch at argument 2 in template
parameter list for ‘template<class P, template<class T> class ST> class
pat_fam’
pat_fam.h:59: erreur: expected a template of type ‘template<class T> class
ST’, got ‘template<class _Tp, class _Alloc> class std::vector’
pat_fam.h:59: erreur: invalid type in declaration before ‘;’ token
pat_fam.h:60: erreur: request for member ‘begin’ in ‘pats’, which is of
non-class type ‘const int’
pat_fam.h:60: erreur: request for member ‘end’ in ‘pats’, which is of
non-class type ‘const int’
pat_fam.h:61: erreur: invalid type argument of ‘unary *’

The same code compiles without error with g++3.4

Thanks a lot.
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Re: problem with template parameter in g++ 4.4.1

[Andrew Pinski]

On Thu, Mar 4, 2010 at 10:16 AM, hannibal81 <jallou07@yahoo.fr> wrote:
> template<typename P, template<typename T> class ST=std::vector>

std::vector has two template arguments not just one.  One of them has
a default value though.  But the C++ standard requires that the number
of template arguments to match inside a template argument, this code
is invalid.  GCC before 4.3 accepted the code as an "undocumented
extension" (undocumented meaning it was a bug).

Thanks,
Andrew Pinski