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Linker Error Undefined Reference To Vtable

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Players Characters don't meet the fundamental requirements for campaign Is it legal to bring board games (made of wood) to Australia? I am adding a note because the error message is deceptive. (This was with gcc version 4.6.3.) share|improve this answer edited Apr 12 '13 at 22:25 Drew Noakes 128k74396489 answered Feb Were students "forced to recite 'Allah is the only God'" in Tennessee public schools? Turned out that I simply forgot to make one of the interface's methods pure virtual (i.e. http://softacoustik.com/undefined-reference/linker-error-undefined-reference-vtable.php

functionB is defined as virtual (NOT PURE VIRTUAL) so it tries to find its definition in Class A itself but you provided its definition in Class B. Is there a difference between u and c in mknod Is it possible to keep publishing under my professional (maiden) name, different from my married legal name? My code: class CGameModule : public CDasherModule { public: CGameModule(Dasher::CEventHandler *pEventHandler, CSettingsStore *pSettingsStore, CDasherInterfaceBase *pInterface, ModuleID_t iID, const char *szName) : CDasherModule(pEventHandler, pSettingsStore, iID, 0, szName) { g_pLogger->Log("Inside game module constructor"); I just added Interval::~Interval(){} and it worked! –Amir Oct 11 '11 at 0:39 add a comment| up vote 1 down vote I had the same problem.

Error Undefined Reference To Vtable For Qt

more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed In my main code where I derived from this class, the linker tried to connect my class to the base class and his vtable. This is probably a QtCreator related bug, this appens with QtCreator 3.3.2 from revision 3af3fe7ad3 c++ qt share|improve this question edited Apr 23 '15 at 8:54 asked Apr 23 '15 at

Players Characters don't meet the fundamental requirements for campaign What is the difference (if any) between "not true" and "false"? The compiler output is below, including the rather strange linker error. What to do when you've put your co-worker on spot by being impatient? Undefined Reference To `typeinfo For Were students "forced to recite 'Allah is the only God'" in Tennessee public schools?

he probably done undefined private default constructor so it cannot be used, e.g. The Vtable Symbol May Be Undefined Because The Class Is Missing Its Key Function You'll probably find that you may have forgotten to define a virtual function ForgottenFunc in your fake class. Remember, arguments types differentiate functions just like names in C++, a Collide(Shape) is different from a Collide(Polygon). http://stackoverflow.com/questions/7720205/linking-error-undefined-reference-to-vtable-for-xxx Since there was no code using the virtual functions (yet), the compiler or linker neglected to put actual function bodies in place.

As the constructors and destructors can be empty, I recommend you just add them to the class definition in the header file: class Machine { public: Machine() {} // Constructor with Undefined Reference To Vtable For Destructor Red balls and Rings What is a Peruvian Word™? more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed In between, keep compiling to see when it starts to fail.

The Vtable Symbol May Be Undefined Because The Class Is Missing Its Key Function

Is it correct to write "teoremo X statas, ke" in the sense of "theorem X states that"? http://stackoverflow.com/questions/17865440/linker-error-undefined-reference-to-vtable The don't have to contain anything and can be empty, the just have to be defined. Error Undefined Reference To Vtable For Qt I have seen many classes where a virtual function is declared without curly braces. –stalin Jun 8 '15 at 16:28 @stalin if you declare if without curly braces, that Undefined Reference To Vtable For Constructor basically about inheritance. –Gilad Mar 1 '13 at 10:03 Either make Machine::reserveSeats and Machine::availableSeats pure virtual, or provide a default implementation for them. –Tom Knapen Mar 1 '13 at

Not having those will give you a general linker fail. useful reference I had the following code in the class definition: class ScreenWidget : public QGLWidget { Q_OBJECT // must include this if you use Qt signals/slots ... }; I had to remove all virtual methods should be defined. Thanks for your help EDIT: Answer: The file was not compiled by moc. Undefined Reference To Vtable For C++

When linker says "undefined reference to vtable for IBase" it basically means that Derived has vtable reference to IBase but it can't find any compiled object code of IBase to look Different precision for masses of moon and earth online N(e(s(t))) a string UV lamp to disinfect raw sushi fish slices Can't a user change his session information to impersonate others? When linking libraries into an executable they are done in the order they are declared. http://softacoustik.com/undefined-reference/linker-error-undefined-reference-to-vtable-for.php People searching for this error would most likely need his solution instead of yours. –Tim Dec 24 '13 at 12:00 3 -1 This may be the solution to your problem,

For example: class Base { virtual void method1(); // throws undefined reference error. } Change the above declaration to the below one, it will work fine. Undefined Reference To Vtable Qobject Polfer Jun 17 '10 at 20:00 1 I totally missed that the error message specifies a function. Thanks for sharing!

The problems you are having is because you don't have a construct or destructor in your classes.

If a header is to be copied somewhere else, the build system should update the copy automatically as soon as the original is modified, and before any inclusion in another file. There are some cases where it's justified to leave out the definition for a declared function, but they are very rare. I thought it was declared in the .h when I posted this. - Duly noted. - That was an extra bracket I added by mistake when stripping the documentation. - As Undefined Reference To Vtable For Class C++ Class C Contains: Now you're writing a Class C in which you are going to derive it from Class A.

To summarize, I would say that if you've stared at the class long enough and can't see what possible syntax problem could be causing it, look for build issues like a The solution was to declare at least one of the virtual functions' bodies outside the class declaration, like this: //----------------------------------------- // libbase.h class base { public: base() { } virtual ~base() I keep getting a vtable linker error for a class that doesnt involve any virtual functions. get redirected here Much like a normal linker error, it's because the compiler knew what you were talking about, but the linker couldn't find the definition.

This is probably a QtCreator related bug, this appens with QtCreator 3.3.2 from revision 3af3fe7ad3. Log in to Reply Svenn-Arne Dragly says: July 30, 2013 at 23:47 Glad to hear you figured it out. If all else fails then one way to debug this error is to build minimal program that does compile and then keep changing it so it gets to the state you Ended up spending 4+ hours in trying to find out what else could be wrong... –ShitalShah May 10 at 18:29 In my case we had abstract class that didn't

In Visual Studio I created a x64 build config. –Alex Black Jul 7 '09 at 23:07 1 Is there a way to confirm the 3rd party library is 64bit? qmake make clean make Should you still have trouble, make sure that qmake is actually generating your .moc files for any objects that need them. The error message is really misleading. –mishmashru Apr 24 '13 at 17:14 | show 2 more comments up vote 50 down vote Qt C++ will show this error when you change more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed

thanks –wanderameise Jan 30 '14 at 17:00 1 Also, if you forget to add the class to the *.pro file's HEADER's section you'll get the same error. What is the meaning of the so-called "pregnant chad"? Uploading a preprint with wrong proofs How to unlink (remove) the special hardlink "." created for a folder? Compute the Eulerian number Uploading a preprint with wrong proofs Why does Mal change his mind?

namespace Dasher { class CEvent; class CEventHandler; class CDasherComponent; }; /// \ingroup Core /// @{ class Dasher::CDasherComponent { public: CDasherComponent(Dasher::CEventHandler* pEventHandler, CSettingsStore* pSettingsStore); virtual ~CDasherComponent(); void InsertEvent(Dasher::CEvent * pEvent); virtual void When you have virtual methods undeclared in an inherited class, the compiler will yield "undefined reference to `vtable for classname`", instead of "undefined reference to `classname::methodname`" Log in to Reply Joe share|improve this answer edited Feb 11 '15 at 15:28 skuntsel 9,39692451 answered Feb 11 '15 at 15:23 Iulian Popa 6111 add a comment| up vote 5 down vote This can happen Eclipse says: Building target: LinkProblem Invoking: GCC C++ Linker g++ -L/home/notroot/workspace/somelib-3/somelib/target/bin -o"LinkProblem" ./src/LinkProblem.o -lsomelib1 -lpthread -lsomelib2 -lsomelib3 ./src/LinkProblem.o: In function `main': /home/notroot/workspace/LinkProblem/Debug/../src/LinkProblem.cpp:17: undefined reference to `SomeClass::close()' ./src/LinkProblem.o: In function `SomeOtherClass': /home/notroot/workspace/somelib-3/somelib/include/sql/somefile.h:148:

My header file went in a library somewhere, but all the virtual functions were declared 'inline' in the class declaration. The problems went away by correctly running the qt moc (meta object compiler) and compiling+including these moc-generated files correctly. One of these files should have main().