Hi,
I'm new to std::auto_ptr<> and wanted to use it with
a base class and several derived classes.
I'm using gcc 3.3.5 and get a compile error I don't know
how to resolve when compiling the following (in file testInteger.cc) :
line 38: std::auto_ptr<H Integer> d(new HInteger(5));
line 39: std::auto_ptr<H Object> e(new HObject());
line 40: e= d;
Here is the error
/usr/include/c++/3.3.5/memory: In member function `std::auto_ptr< _Tp>&
std::auto_ptr<_ Tp>::operator=( std::auto_ptr<_ Tp1>&) [with _Tp1 =
HInteger,
_Tp = HObject]':
testInteger.cc: 40: instantiated from here
/usr/include/c++/3.3.5/memory:237: error: no matching function for call to `
std::auto_ptr<H Object>::reset( HInteger*)'
/usr/include/c++/3.3.5/memory:316: error: candidates are: void
std::auto_ptr<_ Tp>::reset(_Tp* ) [with _Tp = HObject]
HInteger is derived from HNumber which is derived from HObject.
As I'm not familiar with auto_ptr, I tested this with a trivial
example: a class Base and a class Derived and all of the following
compiles fine:
std::auto_ptr<B ase> a(new Base());
std::auto_ptr<D erived> b(new Derived());
std::auto_ptr<B ase> c(new Derived());
a= b;
Originally, my 'root' class HObject was abstract (had pure virtual members),
but removing that didn't change this error message.
So I guess one of my classes HObject, HNumber, or HInteger is missing
a member function, but I don't know what that could be. I do not
hide any of the functions that may be constructed by the compiler
(default or copy c'tor, assignment operator). The destructor is
virtual and public in all 3 classes.
Any hint appreciated, thanks,
Stephan 2 4570
Stephan Hoffmann wrote: Hi,
I'm new to std::auto_ptr<> and wanted to use it with a base class and several derived classes.
I'm using gcc 3.3.5 and get a compile error I don't know how to resolve when compiling the following (in file testInteger.cc) :
line 38: std::auto_ptr<H Integer> d(new HInteger(5)); line 39: std::auto_ptr<H Object> e(new HObject()); line 40: e= d;
Here is the error /usr/include/c++/3.3.5/memory: In member function `std::auto_ptr< _Tp>& std::auto_ptr<_ Tp>::operator=( std::auto_ptr<_ Tp1>&) [with _Tp1 = HInteger, _Tp = HObject]': testInteger.cc: 40: instantiated from here /usr/include/c++/3.3.5/memory:237: error: no matching function for call to ` std::auto_ptr<H Object>::reset( HInteger*)' /usr/include/c++/3.3.5/memory:316: error: candidates are: void std::auto_ptr<_ Tp>::reset(_Tp* ) [with _Tp = HObject]
HInteger is derived from HNumber which is derived from HObject.
Assuming that the derivation is public, this code compiles well on
comeau online, also on g++ 3.4.2. May be you need to upgrade the
compiler.
Hi,
I found the problem, it didn't have anything to do with auto_ptr.
I had mistakenly derived HInteger from HObjectPtr, which is
a typedef for std::auto_ptr<H Object>, instead of HObject.
Thanks, Stephan
Stephan Hoffmann wrote: Hi,
I'm new to std::auto_ptr<> and wanted to use it with a base class and several derived classes.
I'm using gcc 3.3.5 and get a compile error I don't know how to resolve when compiling the following (in file testInteger.cc) :
line 38: std::auto_ptr<H Integer> d(new HInteger(5)); line 39: std::auto_ptr<H Object> e(new HObject()); line 40: e= d;
Here is the error /usr/include/c++/3.3.5/memory: In member function `std::auto_ptr< _Tp>& std::auto_ptr<_ Tp>::operator=( std::auto_ptr<_ Tp1>&) [with _Tp1 = HInteger, _Tp = HObject]': testInteger.cc: 40: instantiated from here /usr/include/c++/3.3.5/memory:237: error: no matching function for call to ` std::auto_ptr<H Object>::reset( HInteger*)' /usr/include/c++/3.3.5/memory:316: error: candidates are: void std::auto_ptr<_ Tp>::reset(_Tp* ) [with _Tp = HObject]
HInteger is derived from HNumber which is derived from HObject.
As I'm not familiar with auto_ptr, I tested this with a trivial example: a class Base and a class Derived and all of the following compiles fine:
std::auto_ptr<B ase> a(new Base()); std::auto_ptr<D erived> b(new Derived()); std::auto_ptr<B ase> c(new Derived()); a= b;
Originally, my 'root' class HObject was abstract (had pure virtual members), but removing that didn't change this error message.
So I guess one of my classes HObject, HNumber, or HInteger is missing a member function, but I don't know what that could be. I do not hide any of the functions that may be constructed by the compiler (default or copy c'tor, assignment operator). The destructor is virtual and public in all 3 classes.
Any hint appreciated, thanks,
Stephan This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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