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Link Error Undefined Reference To Vtable

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Browse other questions tagged c++ gcc g++ or ask your own question. Join them; it only takes a minute: Sign up Linker error: undefined reference to vtable [duplicate] up vote 2 down vote favorite This question already has an answer here: What is 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 I'm using MinGW with GCC and GNU-Make. Check This Out

Movie about a man who becomes a genius because of a brain tumor? View all posts by Svenn-Arne Dragly Posted on January 3, 2010September 18, 2014Author Svenn-Arne DraglyCategories C++, Programming, Qt, TechnicalTags C++, cplusplus, errors, Programming 16 thoughts on “Fixing "undefined reference to `vtable When compiling this I have no compilation errors. Exception vs empty result set when the inputs are technically valid, but unsatisfiable How to tell if your flight has an air-bridge or stairs? read this post here

Error Undefined Reference To Vtable For Qt

When you do these steps the compiler/linker will no longer complain. The problems went away by correctly running the qt moc (meta object compiler) and compiling+including these moc-generated files correctly. 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() asked 5 years ago viewed 24510 times active 5 months ago Blog How Do Software Developers in New York, San Francisco, London and Bangalore… Related 160Undefined reference to static class member133g++

Very rudimentary, still easy to overlook and puzzling if you can't connect the linker diagnostic to the root cause. The others are obvious, and thus unhelpful. –Edgar Bonet Jun 10 '14 at 11:20 | show 1 more comment up vote 21 down vote Undefined reference to vtable may occur due Another possibility is that the class in question once didn't belong to Qt meta object system (that is, it had no Q_OBJECT or maybe didn't inherit from QObject at all), so Undefined Reference To Vtable For C++ This will save your teammates from repeating your frustration.

Thanks for the responses and the link to the GCC FAQ. The Vtable Symbol May Be Undefined Because The Class Is Missing Its Key Function Apr 27, 2012 at 10:50pm UTC codekiddy (783) Try this, 1
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// classes.h #ifndef CLASSES_H #define CLASSES_H #ifdef BUILDING_DLL #define DLL_INTERFACE __declspec(dllexport) #else #define DLL_INTERFACE __declspec(dllimport) #endif class DLL_INTERFACE baseClass { share|improve this answer answered Apr 23 '15 at 8:57 AMDG 650519 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Sign http://stackoverflow.com/questions/15154980/linker-error-undefined-reference-to-vtable When you use the class, you get the linker error.

I am 99% sure I'm linking to the correct library). Undefined Reference To `typeinfo For Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count). 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. In short, define every function you declare, except for pure virtuals.

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

If you are denied entry to a country at the airport, can you chose to fly to another destination? http://stackoverflow.com/questions/1095298/gcc-c-linker-errors-undefined-reference-to-vtable-for-xxx-undefined-refere The first thing I'd do is to put the class declaration in a separate header file, perhaps the build system isn't scanning implementation files. Error Undefined Reference To Vtable For Qt Why are the railings in Rivendell so low? Undefined Reference To Vtable For Constructor std::string += operator cannot pass 0 as argument My boss asked asked if my colleague is underperforming The codegolf object A tearful farewell How do I use mathmode in tables to

C++ Information Tutorials Reference Articles Forum Forum BeginnersWindows ProgrammingUNIX/Linux ProgrammingGeneral C++ ProgrammingLoungeJobs Home page | Privacy policy© cplusplus.com, 2000-2016 - All rights reserved - v3.1Spotted an error? his comment is here It has 7-pointed leaves What is this game from this promotional image for joysticks? One of these files should have main(). Note on ROS and Catkin build system If you were compiling above set of classes in ROS using catkin build system then you will need following lines in CMakeLists.txt: add_executable(myclass src/myclass.cpp Undefined Reference To Vtable Q_object

I couldn't find a solution for 2 hours. –problemofficer Nov 24 '10 at 16:13 1 Thanks, this was exactly what was wrong with me. –Chance Mar 16 '11 at 17:14 Not having those will give you a general linker fail. After you separated/moved the implementation to .cpp, the header file now has just the prototypes of the member functions inside the class. http://globalinfoindex.com/undefined-reference/link-error-undefined-reference-to.php share|improve this answer answered May 10 at 20:35 ShitalShah 11k25348 add a comment| up vote 1 down vote I got this error in the following scenario Consider a case where you

These causes doesn't seem to be true. Undefined Reference To Vtable For Destructor up vote 83 down vote For what it is worth, forgetting a body on a virtual destructor generates the following: undefined reference to `vtable for CYourClass'. share|improve this answer edited Aug 25 '15 at 18:31 answered Feb 14 '11 at 18:34 Rick Smith 3,96963651 11 +1000 - this exactly solved my problem. –Nathan Osman Jun 2

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J Log in to Reply Eric says: September 22, 2012 at 02:26 I still am getting errors even if I combine all .h and .cpp code into main.cpp. classes.h 1
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// classes.h #ifndef CLASSES_H #define CLASSES_H #ifdef BUILDING_DLL #define DLL_INTERFACE __declspec(dllexport) #else #define DLL_INTERFACE __declspec(dllimport) #endif class DLL_INTERFACE baseClass { public: virtual void testFunc(); }; class DLL_INTERFACE derivedClass : Is it worth sending a manned mission to a black hole? Undefined Reference To Vtt Thanks for your help EDIT: Answer: The file was not compiled by moc.

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 Browse other questions tagged c++ g++ or ask your own question. The Loose Astronaut Why isn't Almond Milk (and other non-animal based 'milk') considered juice? http://globalinfoindex.com/undefined-reference/link-error-undefined-reference.php The compiler was complaining about this one and two other constructors in which there was no error at all.

So a working version of your class looks like this: class fourSided { private: int x; int y; Point point; int width; int height; Color color; Rect rect; public: fourSided(); fourSided( The number of methods are the same 4. share|improve this answer answered Nov 8 '15 at 12:37 crw4096 1 add a comment| up vote 0 down vote It's also possible that you get a message like SomeClassToTest.host.o: In function