* g++ 3.4 more restrictive than g++ 3.3 ?
@ 2005-07-15 12:47 Mathieu Fluhr
2005-07-15 13:09 ` Oliver Kullmann
0 siblings, 1 reply; 3+ messages in thread
From: Mathieu Fluhr @ 2005-07-15 12:47 UTC (permalink / raw)
To: gcc-help
Hello all
I'm just wondering about some differences between g++ 3.3 (3.3.6) and
g++ 3.4 (3.4.5). Please have a look to this piece of code:
---8<---------------------------------------------
#include <iostream>
template <class ValueType>
class A
{
protected:
ValueType m_Field;
};
template <class ValueType>
class B : public A<ValueType>
{
void TestParam(ValueType i)
{
m_Field = i;
}
};
int main(void)
{
return 0;
}
---8<---------------------------------------------
As far as I know the C++ language, syntax seems to be correct, and g++
3.3 does not output any error/warning (even with -Wall option). The
problem is that g++ 3.4 (and 4.0 btw) outputs the following:
For g++ 3.4:
Inherit.cpp: In member function `void
B<ValueType>::TestParam(ValueType)':
Inherit.cpp:16: error: `m_Field' undeclared (first use this function)
Inherit.cpp:16: error: (Each undeclared identifier is reported only once
for each function it appears in.)
For g++ 4.0:
Inherit.cpp: In member function 'void
B<ValueType>::TestParam(ValueType)':
Inherit.cpp:16: error: 'm_Field' was not declared in this scope
The very weird thing is that if I change the line 16 from
m_Field = i;
to
this->m_Field = i;
everything works without any kind of problem !!! So is this behaviour
normal ?
Best Regards,
Mathieu Fluhr
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: g++ 3.4 more restrictive than g++ 3.3 ?
2005-07-15 12:47 g++ 3.4 more restrictive than g++ 3.3 ? Mathieu Fluhr
@ 2005-07-15 13:09 ` Oliver Kullmann
[not found] ` <1121436079.21076.12.camel@localhost.localdomain>
0 siblings, 1 reply; 3+ messages in thread
From: Oliver Kullmann @ 2005-07-15 13:09 UTC (permalink / raw)
To: Mathieu Fluhr; +Cc: gcc-help
On Fri, Jul 15, 2005 at 02:46:50PM +0200, Mathieu Fluhr wrote:
> Hello all
>
> I'm just wondering about some differences between g++ 3.3 (3.3.6) and
> g++ 3.4 (3.4.5). Please have a look to this piece of code:
>
> ---8<---------------------------------------------
> #include <iostream>
>
> template <class ValueType>
> class A
> {
> protected:
> ValueType m_Field;
> };
>
> template <class ValueType>
> class B : public A<ValueType>
> {
> void TestParam(ValueType i)
> {
> m_Field = i;
> }
> };
>
> int main(void)
> {
> return 0;
> }
>
> ---8<---------------------------------------------
>
> As far as I know the C++ language, syntax seems to be correct, and g++
> 3.3 does not output any error/warning (even with -Wall option). The
> problem is that g++ 3.4 (and 4.0 btw) outputs the following:
>
> For g++ 3.4:
>
> Inherit.cpp: In member function `void
> B<ValueType>::TestParam(ValueType)':
> Inherit.cpp:16: error: `m_Field' undeclared (first use this function)
> Inherit.cpp:16: error: (Each undeclared identifier is reported only once
> for each function it appears in.)
>
> For g++ 4.0:
>
> Inherit.cpp: In member function 'void
> B<ValueType>::TestParam(ValueType)':
> Inherit.cpp:16: error: 'm_Field' was not declared in this scope
>
>
> The very weird thing is that if I change the line 16 from
> m_Field = i;
> to
> this->m_Field = i;
>
> everything works without any kind of problem !!! So is this behaviour
> normal ?
>
Hi,
that's exactly correct: class B has a dependent base class, and
thus members of this base class have to be qualified (see the standard,
paragraph 14.6.2, point 4).
Oliver
P.S. A minor point: I think "int main(void)" is not standard
--- according to 3.6.1, point 2 only "int main()" is guaranteed
to work.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: g++ 3.4 more restrictive than g++ 3.3 ?
[not found] ` <1121436079.21076.12.camel@localhost.localdomain>
@ 2005-07-15 14:36 ` Oliver Kullmann
0 siblings, 0 replies; 3+ messages in thread
From: Oliver Kullmann @ 2005-07-15 14:36 UTC (permalink / raw)
To: Mathieu Fluhr; +Cc: gcc-help
On Fri, Jul 15, 2005 at 04:01:19PM +0200, Mathieu Fluhr wrote:
> Thanks for you quick answer. So I assume the best solution is to patch
> all C++ files that brings errors... Lots of work in perspective ;-)
>
but necessary
> BtW, regarding your PS, what is the difference between
> `int main(void)` and `int main()` ?
>
it's just that I'm not aware of text in the standard
granting the use of `int main(void)`, while `int main()`
definitely is correct, so it might be that at some
time in the future `int main(void)` has to be changed
to `int main()`, and so I would avoid it.
Oliver
> Mathieu
>
> On ven, 2005-07-15 at 14:09 +0100, Oliver Kullmann wrote:
> > On Fri, Jul 15, 2005 at 02:46:50PM +0200, Mathieu Fluhr wrote:
> > > Hello all
> > >
> > > I'm just wondering about some differences between g++ 3.3 (3.3.6) and
> > > g++ 3.4 (3.4.5). Please have a look to this piece of code:
> > >
> > > ---8<---------------------------------------------
> > > #include <iostream>
> > >
> > > template <class ValueType>
> > > class A
> > > {
> > > protected:
> > > ValueType m_Field;
> > > };
> > >
> > > template <class ValueType>
> > > class B : public A<ValueType>
> > > {
> > > void TestParam(ValueType i)
> > > {
> > > m_Field = i;
> > > }
> > > };
> > >
> > > int main(void)
> > > {
> > > return 0;
> > > }
> > >
> > > ---8<---------------------------------------------
> > >
> > > As far as I know the C++ language, syntax seems to be correct, and g++
> > > 3.3 does not output any error/warning (even with -Wall option). The
> > > problem is that g++ 3.4 (and 4.0 btw) outputs the following:
> > >
> > > For g++ 3.4:
> > >
> > > Inherit.cpp: In member function `void
> > > B<ValueType>::TestParam(ValueType)':
> > > Inherit.cpp:16: error: `m_Field' undeclared (first use this function)
> > > Inherit.cpp:16: error: (Each undeclared identifier is reported only once
> > > for each function it appears in.)
> > >
> > > For g++ 4.0:
> > >
> > > Inherit.cpp: In member function 'void
> > > B<ValueType>::TestParam(ValueType)':
> > > Inherit.cpp:16: error: 'm_Field' was not declared in this scope
> > >
> > >
> > > The very weird thing is that if I change the line 16 from
> > > m_Field = i;
> > > to
> > > this->m_Field = i;
> > >
> > > everything works without any kind of problem !!! So is this behaviour
> > > normal ?
> > >
> >
> > Hi,
> >
> > that's exactly correct: class B has a dependent base class, and
> > thus members of this base class have to be qualified (see the standard,
> > paragraph 14.6.2, point 4).
> >
> > Oliver
> >
> > P.S. A minor point: I think "int main(void)" is not standard
> > --- according to 3.6.1, point 2 only "int main()" is guaranteed
> > to work.
> >
>
--
Dr. Oliver Kullmann
Computer Science Department
University of Wales Swansea
Faraday Building, Singleton Park
Swansea SA2 8PP, UK
http://cs-svr1.swan.ac.uk/~csoliver/
^ permalink raw reply [flat|nested] 3+ messages in thread
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2005-07-15 12:47 g++ 3.4 more restrictive than g++ 3.3 ? Mathieu Fluhr
2005-07-15 13:09 ` Oliver Kullmann
[not found] ` <1121436079.21076.12.camel@localhost.localdomain>
2005-07-15 14:36 ` Oliver Kullmann
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