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Error Undefined Reference To Vtable For Qt

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Can someone take my Wi-Fi signal DOWN? share|improve this answer edited Mar 1 '13 at 11:11 answered Mar 1 '13 at 10:02 Some programmer dude 217k17152263 thanks for your fast reply! Also, this makes a lot more sense to me after reading this, which I just found after some searching: http://gcc.gnu.org/faq.html#vtables Thanks again. Consider the following code, which is a minimum to produce the error: class T : public QObject, public QGraphicsItem { Q_OBJECT public: T() {} QRectF boundingRect() const {return QRectF();} void paint(QPainter navigate here

As a side effect, please note that only for this particular virtual function you won't get the traditional linker error like you are missing function foo. 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 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 g++ test.cpp -o test /tmp/ccDfCj4N.o: In function `Interval::Interval()': test.cpp:(.text._ZN8IntervalC2Ev[Interval::Interval()]+0x9): undefined reference to `vtable for Interval' /tmp/ccDfCj4N.o: In function `IntInterval::~IntInterval()': test.cpp:(.text._ZN11IntIntervalD0Ev[IntInterval::~IntInterval()]+0x1d): undefined reference to `Interval::~Interval()' /tmp/ccDfCj4N.o: In function `IntInterval::~IntInterval()': test.cpp:(.text._ZN11IntIntervalD1Ev[IntInterval::~IntInterval()]+0x1d): undefined reference

Error Undefined Reference To Vtable For Qt

A possible cause of the error message OP reported would be failing to compile or link one translation unit. In my case, I thought I had replaced the declaration that used char *xml as the parameter with one using the unnecessarily troublesome const char *xml, but instead, I had created The Loose Astronaut Why isn't Almond Milk (and other non-animal based 'milk') considered juice? Topic archived.

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 It compiles, but the resulting library is missing necessary references 1 Strange error message when a class method is missing 0 Should the order of linked libraries make a difference in share|improve this answer edited Jan 23 '11 at 15:56 answered Jan 23 '11 at 15:45 Troubadour 11k21836 2 +1 Awesome, I did not know about this! –Ali Feb 14 '11 Undefined Reference To Vtable For C++ 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

You are describing the behaviour of one particular compiler; other compilers may behave differently, so playing games with declaration order to mask the error is not portable. –Mike Seymour Oct 11 What is this shrub/plant? Vim: what are all the possible swapfile extensions? http://stackoverflow.com/questions/15154980/linker-error-undefined-reference-to-vtable There are some cases where it's justified to leave out the definition for a declared function, but they are very rare.

How can I fix it? Undefined Reference To `typeinfo For So, I was compiling with an old makefile that had no idea about my new files whatsoever. 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). The header file was not compiled by the moc compiler but was in the .pro file.

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

obj\Debug\main.o||In function `fourSided':| C:\Users\Eric\Desktop\Code\Programs\instincts physics\main.cpp|40|undefined reference to `vtable for fourSided'| C:\Users\Eric\Desktop\Code\Programs\instincts physics\main.cpp|40|undefined reference to `vtable for fourSided'| C:\Users\Eric\Desktop\Code\Programs\instincts physics\main.cpp|51|undefined reference to `vtable for fourSided'| C:\Users\Eric\Desktop\Code\Programs\instincts physics\main.cpp|51|undefined reference to `vtable for fourSided'| http://stackoverflow.com/questions/1095298/gcc-c-linker-errors-undefined-reference-to-vtable-for-xxx-undefined-refere None of these methods is virtual, but defining one as virtual, to force the creation of a vtable, does not work. Error Undefined Reference To Vtable For Qt Note that a destructor must be defined even if it is declared pure-virtual [class.dtor]/7. Undefined Reference To Vtable For Constructor Why are some people so paranoid about music theory?

When compiling this I have no compilation errors. http://robertwindows.com/undefined-reference/cmake-linking-error-undefined-reference.html share|improve this answer answered Aug 7 '10 at 13:06 mgiuca 13.6k23760 3 Thank You. Can you benefit from a second casting of Armor of Agathys while the first is still active? why are terminal consoles still used? Undefined Reference To Vtable Q_object

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 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. After running qMake once more, life was good again. –Alex Hendren Nov 6 '13 at 7:32 | show 3 more comments up vote 17 down vote If you want to define his comment is here Then add your class using QtCreator assistant : Add New...

Post navigation Previous Previous post: Automount an SSH server in UbuntuNext Next post: Fixing a bug with python-visual in Ubuntu Karmic Proudly powered by WordPress Search: Forum General C++ Programming Derived Undefined Reference To Vtable For Destructor I get a "undefined reference to vtable for TestBench" on all these methods, in the .o file that obviously has been linked in. Success!

You could be on to something though.

Browse other questions tagged c++ g++ or ask your own question. This file was compiled, but not linked, so the linker was complaining about being unable to find it. The error message is really misleading. –Offirmo Mar 4 '13 at 14:47 32 For Qt users: you can get this same error if you forget to moc a header. –Chris Undefined Reference To Vtt 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

Is there a way to confirm the static libraries I am linking to are 64bit? I kept believing I had all methods as pure abstract while one method hiding out. I had the following: class I { virtual void Foo()=0; }; And in another file (included in the compilation and linking, of course) class C : public I{ void Foo() { weblink If you can't figure it out, see if you can create a simple example that reproduces the error and post it here.

I've also cleaned the environment. Why is Cuba still leasing Guantanamo Bay to the US? share|improve this answer answered Jun 12 '15 at 14:31 vitke 323 3 That would make no difference at all, you must have had the error elsewhere and inadvertantly fixed it. For-each library in order: Check unresolved dependencies and see if the lib resolves them.

Omitting its implementation means you won't have a vtable, and thus won't be able to construct the class (hence these errors). A tearful farewell Why are some people so paranoid about music theory? Help is appreciated. 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

I did a full rebuild before posting this question ;) –AMDG Apr 23 '15 at 8:26 Is the header listed in HEADERS in the .pro file? –Wintermute Apr 23 Why Does Everyone Assume that the Architect was Telling the Truth About there Being Previous "Ones"? But one linker errors : undefined reference to `vtable for StorageManager' This error is labeled on the class definition line : class StorageManager : public QObject { I know this kind How much of my income should I put towards paying off student loans vs saving for a house?