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Error Undefined Reference To Vtable For Qt

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This way you can try find the problem in your code. The don't have to contain anything and can be empty, the just have to be defined. What is this aircraft with elaborate folding wings? Unfortunately, I'm still getting the same error, and I don't quite know what is going on. this contact form

share|improve this answer answered Nov 4 '14 at 16:28 Bretzelus 314 add a comment| up vote 2 down vote This is a terrible error because it seems people have seemingly assumed Forever Generate all brace-strings of length n How to format a number with an error? public: fourSided() { this -> x = 0; this -> y = 0; this -> width = 0; this -> height = 0; this -> color = BLACK; this -> point What is the inner cover of the winter shoes called in English?

Error Undefined Reference To Vtable For Qt

Are endothermic bombs possible? In my case, there was another definition of the same class, due to a duplication of the source file. Have you any other tips?

How to use breakpoints for debugging What if passport is lost and home country has no diplomatic presence? In short, define every function you declare, except for pure virtuals. 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 Undefined Reference To Vtable For C++ How come the Sun's gravity can hold distant planets in orbit, but cannot rip humans off Earth?

Thanks for sharing! The Vtable Symbol May Be Undefined Because The Class Is Missing Its Key Function Log in to Reply hila says: January 4, 2014 at 14:33 hi!!! If you are using Qt or a project with a Makefile, you could just run these three commands (the first only applies to Qt projects). http://stackoverflow.com/questions/15154980/linker-error-undefined-reference-to-vtable I get a "undefined reference to vtable for TestBench" on all these methods, in the .o file that obviously has been linked in.

g++ -DBUILDING_DLL -c -o plugin.o classes.cpp g++ -shared -o plugin.dll plugin.o plugin.o:classes.cpp:(.text$_ZN9baseClassC2Ev[baseClass::baseClass()]+0x8): undefined reference to `vtable for baseClass' collect2: ld returned 1 exit status mingw32-make: *** [plugin.dll] Error 1 The problem Undefined Reference To `typeinfo For Or maybe it isn't generated at all. Is it worth sending a manned mission to a black hole? 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

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

Also make sure you change your makefile to accomodate/add the new .o file that is built from the new .cpp file you just created. He's missing definitions for several virtual functions, so even if you managed to get G++ to emit a vtable, the vtable itself will cause more link errors for the undefined virtuals. 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 Undefined Reference To Vtable For Constructor 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

Also you shall define destructor as virtual. weblink Also the linker will only take the methods/functions required to resolve currently outstanding dependencies. Thanks you saved my time and effort. –Haider Aug 28 '12 at 10:19 Interesting that in my case it happens with 'pure virtuals' only! 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 Undefined Reference To Vtable Q_object

It looks like CGameModule has an extra } at the end (after the }; // for the class). I'm using g++ version 4.9.1 under Ubuntu. A tearful farewell Why are some people so paranoid about music theory? navigate here What is wrong with the code?

Thank you. –iizno Mar 25 '13 at 12:25 add a comment| Not the answer you're looking for? Undefined Reference To Vtable For Destructor I think I'm doing something wrong with constructors, but I'm not sure what. Join them; it only takes a minute: Sign up Q_OBJECT throwing 'undefined reference to vtable' error [duplicate] up vote 41 down vote favorite 15 This question already has an answer here:

My class looked like this: //----------------------------------------- // libbase.h class base { public: base() { } virtual ~base() { } virtual int foo() { return 0; } } //----------------------------------------- //----------------------------------------- // libbase.cpp

It is possible to compile the class without defining the virtual functions, but as soon as the linker tries to look up the function definitions it finds nothing and fails with Since I've been relatively knew to C++ and still learning, I haven't experimented with Polymorphism all that much. No new replies allowed. Undefined Reference To Vtt 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:

Should I defragment my SSD? Is it ethical to use proprietary (closed-source) software for scientific computation? Omitting it didn't make a difference to compilation, but if you think it's a good idea, then thanks for the advice! http://compsyscon.com/undefined-reference/cmake-linking-error-undefined-reference.html If you don't define it, the vtable will be undefined as well.

Reason: functionA is defined as pure virtual and its definition is provided in Class B. Seriously, there should be a more specific article on some pages out there about this issue. Good luck! Dynamic SOQL query Students trying to negotiate away penalties for late submission of coursework Listing sequence with rules How come the Sun's gravity can hold distant planets in orbit, but cannot

Do handstand push-ups hit all the three shoulder heads? I was misdirected by the explicit initial reference to constructors and destructors until I read a reference in another post. Dec 8 '15 at 22:28 this may be a different issue, but my problem was just not having an implementation for a non-virtual destructor (was switching to unique / Is there a way to confirm the static libraries I am linking to are 64bit?

How do I ensure my code/project is 64bit? Start from the bottom and build up everything again piece by piece, if possible. How do I use mathmode in tables to write physics formulae? I've included the header files, linked to their libraries, but I still get linker errors.

So if you have a header which looks like this: #ifndef MESH_H #define MESH_H class Mesh { public: Mesh(); ~Mesh(); virtual void draw(); }; #endif // MESH_H You must at least 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 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?