cvblob compile error in Visual C++ 6.0 - c++

I'm using Microsoft Visual C++ 6.0 and Microsoft Visual Studio 2008 to develop an academic computer vision project.
In this project i need to use OpenCV 1.1 (http://opencv.willowgarage.com/) and CvBlob (http://code.google.com/p/cvblob/).
I tried to compile this project with Microsoft Visual Studio 2008 and it compiles without errors.
With Visual C++ 6.0 i got a lot of errors.
OpenCV are not responsible of this behavior, because a trivial project with only OpenCV (without CvBlob) works well.
To understand the errors better I made an empty project with only the CvBlob inclusion.
I paste here a brief summary of the errors:
cvcontour.cpp(253) : error C2371: 'i' : redefinition; different basic types (and others similar to this. i solved with variable redefinition, every time)
cvcontour.cpp(318) : error C2664: 'thiscall std::vector<struct CvPoint,class std::allocator<struct CvPoint> >::std::vector<struct CvPoint,class std::allocator<struct CvPoint> >(unsigned int,const struct CvPoint &,const class std::allocator<struct CvPoint> &)' : cannot convert parameter 1 from 'class std::deque<struct CvPoint,class std::allocator<struct CvPoint> >::iterator' to 'unsigned int' No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
cvtrack.cpp(278) : error C2440: 'initializing' : cannot convert from 'struct cvb::CvTrack *const ' to 'struct cvb::CvBlob *' Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
Have you ideas on how can i solve these problems?
Thanks in advance for the help!
-------- UPDATE --------
I tried to edit and correct the code in order to elminate the three errors in my question.
The error C2664 seems to be the more difficult to cirmumvent...
I have replaced the indicted line
return new CvContourPolygon(dq.begin(), dq.end());
where CvContourPolygon is a typedef std::vector<CvPoint> CvContourPolygon;
with
deque<int>::iterator dq_it;dq_it = dq.begin();
CvContourPolygon v_tmp;
v_tmp.push_back(*dq_it);
while (dq_it != dq.end()){
v_tmp.push_back(*dq_it++);
}
First, what that i wrote is correct? Than, how can i solve the errors that occured from this?
Thank you in advance!
Errors (suppose that the first line is 318:
cvcontour.cpp(319) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class std::deque<struct CvPoint,class std::allocator<struct CvPoint> >::iterator' (or
there is no acceptable conversion)
cvcontour.cpp(321) : error C2664: 'push_back' : cannot convert parameter 1 from 'int' to 'const struct CvPoint &'
Reason: cannot convert from 'int' to 'const struct CvPoint'
No constructor could take the source type, or constructor overload resolution was ambiguous
cvcontour.cpp(322) : error C2679: binary '!=' : no operator defined which takes a right-hand operand of type 'class std::deque<struct CvPoint,class std::allocator<struct CvPoint> >::iterator' (or there is no acceptable conversion)
cvcontour.cpp(322) : fatal error C1903: unable to recover from previous error(s); stopping compilation
Error executing cl.exe.
-------- UPDATE2 --------
This code seems to work correctly!
deque<CvPoint>::iterator dq_it;
dq_it = dq.begin();
CvContourPolygon v_tmp;
for (dq_it = dq.begin(); dq_it != dq.end(); ++dq_it){
v_tmp.push_back(*dq_it);
}
//return new CvContourPolygon(dq.begin(), dq.end());
return &v_tmp;

C2371 - VC6 was sloppy with scope of local variables. Should be able to fix this by making the code use variable names unambiguously.
C2664 - looks like failure to initialize a vector using deque iterators - wrong overload on vector::vector() being called? Probably have to work around this by manually copying the deque elements to the new vector somehow.
C2440 - check the objects are compatible (VS2008 seems to think so) and add the appropriate cast.
EDIT:
Shouldn't your code look like this?
deque<CVPoint>::iterator dq_it;dq_it = dq.begin();
CvContourPolygon v_tmp;
for (dq_it = dq.begin(); dq_it != dq.end(); ++dq_it)
{
v_tmp.push_back(*dq_it);
}

Related

C++ Debugging no '=' operator found in Visual Studio

Visual Studio gives me this error when I try to compile my C++ project:
Severity: Error
Code: C2678
Description: binary '=': no operator found which takes a left-hand operand of type 'const std::string' (or there is no acceptable conversion)
Project: jr
File: c:\program files (x86)\microsoft visual studio 14.0\vc\include\utility
Line: 192
I suppose, somewhere in my project, I'm trying to change constant string.
How do I locate this? How to go about debugging such errors?
The filename and line mentioned in the error are some read-only files by Microsoft. I'd like to locate the error in my code. Here's the excerpt of code around line 192:
_Myt& operator=(const _Myt& _Right)
{ // assign from copied pair
first = _Right.first;
second = _Right.second;
return (*this);
}
You probably want to write code like:
const std::string s;
s = "";
this is why error is saying about const type : 'const std::string'
Other possibility is that you want to assign a value to a string in a const method.

Compiling SQLite with Visual Studio C++ 2013 Throws error for .c file

I have added sqlite3.c file into my project.
And #include. Here is the code:
#include <sqlite3.h>
using namespace std;
int main()
{
return 0;
}
I compile the program and it throws the following error:
1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(15705): error C2440: '=' : cannot convert from 'void *' to 'char *'
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1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(19741): error C2440: '=' : cannot convert from 'void *' to 'sqlite3_mutex *'
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1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(20665): error C2440: '=' : cannot convert from 'void *' to 'char *'
1> Conversion from 'void*' to pointer to non-'void' requires an explicit cast
1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(20677): error C2440: '=' : cannot convert from 'void *' to 'char *'
1> Conversion from 'void*' to pointer to non-'void' requires an explicit cast
1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(21142): error C2440: '=' : cannot convert from 'void *' to 'char *'
1> Conversion from 'void*' to pointer to non-'void' requires an explicit cast
1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(21256): error C2440: '=' : cannot convert from 'void *' to 'char *'
1> Conversion from 'void*' to pointer to non-'void' requires an explicit cast
1>..\..\..\..\..\..\..\libraries\sqlite-amalgamation-3080702\sqlite3.c(21411): error C2440: '=' : cannot convert from 'void *' to 'char *'
But there is no error that a header or file is not found. Everything is found and the errors are just outputted above
I have found the solution. I compiled the C code as C++, but changing it was not enough.
I write it for future visitors:
First, I had to change file's (ONLY FILE) property. Right-click on the file and select properties, under the C/C++, select Advanced and then select Compile As and set it to C (neither default nor C++).
Then, you should make sure that your .c file is compiled without clr. Well, to do that, under the same C/C++ set of menu, select "Common Langugae Runtime Support" and set it to No Support....
I'm using Visual Studio 17 and I would add to this, find the settings for "Precompiled Header" and set that to "Not Using Precompiled Headers".

error C2440 and functors

maybe you would know, I get an error:
error C2440: 'initializing' : cannot convert from 'int'
Conversion from integral type to pointer type requires reinterpret_cast
It goes to ' file in MS VS 2010 folder:
template<class _Other1,
class _Other2>
_Pair_base(_Other1&& _Val1, _Other2&& _Val2)
: first(_STD forward<_Other1>(_Val1)),
second(_STD forward<_Other2>(_Val2))
{ // construct from moved values
}
I was looking for different solutions but could not find a correct one.
The error says
'initializing' : cannot convert from 'int' to 'EnterFunctor *'
The only part of your code you share is
functors.push_back(make_pair(sessionStartFunc,
pair<EnterFunctor*, ExitFunctor*>(NULL,sessionStartExit)));
If NULL is #defined as 0 this gives you an int but you promised a pair of pointers, so as the next line of the error says you can use a cast to make NULL the right type of pointer.

cannot convert parameter

I have this that compiles fine in VC++ 6.0
typedef std::vector<ILBCOM_FieldStruct*> FieldsVector;
FieldsVector m_coll;
FieldsVector::iterator it(&m_coll[Index-1]);
m_coll.erase(it);
I need to compile in Visual Studio C++ 2010
The error message is on the 3rd line:
error C2664: 'std::_Vector_iterator<_Myvec>::_Vector_iterator(const
std::_Vector_iterator<_Myvec> &)' : cannot convert parameter 1 from
'ILBCOM_FieldStruct **' to 'const std::_Vector_iterator<_Myvec> &'
Do you see something wrong?
std::vector<T>::iterator does not have a constructor that converts from T*. It does have a copy constructor:
FieldsVector::iterator it(m_coll.begin()+Index-1);

compile errors log4cxx with __stdcall and Boost 1.47.0

I'll be very pleased if you help.
My IDE is VS2010.
I'm using boost 1.47.0, especially boost::asio.
After some days of developing I decided to add log4cxx.
log4cxx needs to change calling convention to __stdcall
I surprisingly got lots of compiling error. They are ~ 70 errors.
I've googled a bit and found these:
#define BOOST_BIND_ENABLE_STDCALL
#define BOOST_MEM_FN_ENABLE_STDCALL
It helps. Now there are just ~10 errors.
Here there are:
1>ClCompile:
1> main.cpp
1>D:\Development\lib\boost_1_47_0\boost/detail/interlocked.hpp(61): error C2373: '_InterlockedCompareExchange' : redefinition; different type modifiers
1> C:\Program Files\Microsoft Visual Studio 10.0\VC\include\intrin.h(214) : see declaration of '_InterlockedCompareExchange'
1>D:\Development\lib\boost_1_47_0\boost/detail/interlocked.hpp(62): error C2373: '_InterlockedExchange' : redefinition; different type modifiers
1> C:\Program Files\Microsoft Visual Studio 10.0\VC\include\intrin.h(192) : see declaration of '_InterlockedExchange'
1>D:\Development\lib\boost_1_47_0\boost/detail/interlocked.hpp(63): error C2373: '_InterlockedExchangeAdd' : redefinition; different type modifiers
1> C:\Program Files\Microsoft Visual Studio 10.0\VC\include\intrin.h(204) : see declaration of '_InterlockedExchangeAdd'
1>D:\Development\lib\boost_1_47_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(92): error C2446: '==' : no conversion from 'long' to 'long (__stdcall *)(volatile long *,long,long)'
1> Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast
1>D:\Development\lib\boost_1_47_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(92): error C2040: '==' : 'long (__stdcall *)(volatile long *,long,long)' differs in levels of indirection from 'long'
1>D:\Development\lib\boost_1_47_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(92): error C3861: '_InterlockedCompareExchange': identifier not found
1>D:\Development\lib\boost_1_47_0\boost/smart_ptr/detail/spinlock_w32.hpp(62): error C3861: '_InterlockedExchange': identifier not found
1>D:\Development\lib\boost_1_47_0\boost/smart_ptr/detail/spinlock_w32.hpp(62): error C2440: 'initializing' : cannot convert from 'long (__stdcall *)(volatile long *,long)' to 'long'
1> There is no context in which this conversion is possible
1>D:\Development\lib\boost_1_47_0\boost/asio/detail/impl/signal_set_service.ipp(74): error C2664: 'signal' : cannot convert parameter 2 from 'void (__stdcall *)(int)' to 'void (__cdecl *)(int)'
1> None of the functions with this name in scope match the target type
1>D:\Development\lib\boost_1_47_0\boost/asio/detail/impl/signal_set_service.ipp(246): error C2664: 'signal' : cannot convert parameter 2 from 'void (__stdcall *)(int)' to 'void (__cdecl *)(int)'
1> None of the functions with this name in scope match the target type
1>main.cpp(20): warning C4007: 'main' : must be '__cdecl'
How can I solve them?
Any little ideas or hints?
You also need
#define BOOST_USE_WINDOWS_H
and possibly /Gz (__stdcall)
If your code looks something like:
#include "log4cxx/logger.h"
#include "log4cxx/basicconfigurator.h"
#include "log4cxx/helpers/exception.h"
using namespace log4cxx;
using namespace log4cxx::helpers;
int main()
{
//stuff
}
and you compile with -llog4cxx then you should be fine.