C++ :: Undefined Reference To (method Name) When Accessing Method In Static Library
Jan 17, 2013
I've been trying for more than one month to access a method found in a library called libcocosnas_static.a. I'm using Cocos2d-X version 2.0.4. The library has been used many times by my company to make games using cocos2d-1.0.1-x-0.12.0 without any problem.
This is what I've done:
1- I added the include paths of the library to both eclipse and Android.mk
2- Included the .h file using #include "NASPlatformUtil.h"
3- Added the libcocosnas_static.a file to the proj.androidobjlocalarmeabi folder
4- Added "LOCAL_WHOLE_STATIC_LIBRARIES += cocosnas_static" to the Android.mk file
5- Called the function using: NASPlatformUtil:: openUrl("http://xxx.xxx.com/");
I can right click on the function, click Open Declaration and get it without any problem, but the compiler keeps on giving me that dreaded error...
I am modifying a set of static variables inside of the class's member function. The static variables are private. An example of what I'm doing is as below,
utilities.h ----------- class utilities { private: static int num_nodes;
public: void parse_details(char* );
[Code] ....
I get a compilation error in the function void utilities::parse_details(char* filename)
which says: undefined reference to `utilities::num_nodes'
1. Is that mean that Do() is only available for use by Dog itself because Dog is 'oryginal' Dog, and if i create new dogs - instances of oryginal Dog (dog1, dog2 ...) they cant access because Do is only available fo 'oryginal' one? Is that correct thinking?
2. If i would want to have something common (e.g value) for all dogs is that good way to create static field/method for Dog instead of non-static once then all instances of Dog would access Dog static member to get/change it? Just stupid example: static method GetAmountOfLegs() which return 4 Then all instances can take/call that value from Dog. Is that correct thinking?
#include <iostream> using namespace std; struct A { virtual void f() { cout<<"A "; } };
[code]...
I would expect that both examples 2 & 3 will give me the same result.I tried to figure it out but I could not. Both are references of a base class type, that get a derived object.
Q1 : why is the difference between them ?
As I see it, its kind of a mix between pointer - which in case of virtual method that was override in derived class - would give me the derived method (e.g. "B") and between regular object - which in case of virtual method that was override - would give me the specific method (Still "B"). So, example 2 "use" it as a regular object and example 3, "use" it as pointer.
Q2 : How should I refer to it ? I am using VS2008.
I declared a member method to a class in its header file and implemented it in the cpp file. When I build and run the project in XCode, everything works fine. When I try to do it with a makefile, I get undefined symbols linker errors.
I'm pretty sure that there is a weird namespace gotcha that I'm unaware of that LLVM (default OSX compiler) is compensating for that g++ isn't. Or maybe something weird with the optimization? I want the tests running at that level to make sure everything that is volatile is declared as such.
A quick clarification on virtual methods after reading Jumping int C++ by Alex Allain. If a user wanted to extend a class from someone elses library and override its methods that do not contain virtual methods; how would one call the overridden class if it is referred to by its super type
in other words how would someone override a method from someone elses library that does not have virtual keywords.
I would like to avoid throwing things in constructors as much as possible.
Is this good design to have a static class method that checks arguments the caller will give to the constructor. The documentation of the class will say, thou shall call this method to validate thine arguments before calling the constructor, or else segfault may befall thoust.
I have function that returns historical data. I can access it, using file name. If I use file name, it reads that file and saves it to dictionary, so that in the future, if historical data is required for the same file, it does not read it again (it's lazy loading). If no file is supplied to the function, it tries to read file which is given in app settings.
However, for unit testing, I do not want to read any file. Instead, I want it to use small sample of hardcoded historical data. In order to do that, I think, I need to introduce interface to it. Then I can use some IoC to choose between different implementation for unit testing purpose and ordinary launch of application.
Function to get history is given as follows:
public static class Auxiliary { private static Dictionary<string, MyData> _myData; public static MyData GetData(string fileName = null) { // ... } }
I have created default Unit Test project with Visual Studio so, as far as I know, by default it uses MSTest as test runner and MSUnit as unit testing framework but it does not have any IoC container so I should manage NuGet packages for solution and install Unity.
As far as I know, MSUnit (aka Moles) can unit test static methods (it's unconstrained isolation framework, like Typemock Isolator, unlike NUnit) but still many people suggest not to use any static methods for unit testing.
Should I use shim or stub [URL] Stubs should be used for faking external dependencies and here it is not external library, but my own code.
The problem occurs in here, I get access violations, is there a way to this while keeping Display const or is this code valid and my problem is somewhere else and not being caught in the debugger? I tried to make the return types const - but that didn't work .....
//Getters need const twice for this to work? const char* Player::GetName() const {return m_name;} const int Player::GetGrade() const {return m_grade;} const double Player::GetGPA() const {return m_gpa;}
I am writing my program on C++ language. I have one promblem. I need to set signal handler for my process. As the signal is related with the process on system level I have faced the problem.
My program consists several classes. They are connected together. But it doesn't metter in this case. The problem is that I need to access to member and methods of the class from my signal handler. For instance , I have class named Foo at it has some members and methods.
So from my handler I need to call its function and change members.
I understand that compiler should know that this class instances will exist during all program execution.
I have tried to set static member class Foo instance in another class , but this didn't solve the problem.
What is correct approach to do this. How to correctly implement signal handling in such case.
Here is example of my code
Code: class MyContainer{ private: std::vector<Foo> container; public: int removeFromContainer(Foo* aFoo) {
I have a question similar to the one here: [URL] .....
The main difference is I would like to pass a method of derived class as a parameter to some other method in its template base class.
template <typename BaseType> class Base { public: typedef void (Base::*Callback)(int A);
[Code] .....
The above is an example which does not compile. My compiler complains that the two BaseMethod() calls in DerivedMethod() are invalid uses of non-static member function.
Is this not possible to do, or is my syntax simply wrong? All I want is to be able to pass as an an argument to a method in the base class from the derived class some callback as a variable for the base class to invoke later.
What are the workarounds for accessing the non-static member variables of some class(Say A) inside static member functions of another class(Say B)? I am coding in c++. Class A is derived with public properties of class B. Any pointers?
I'm making a program that's essentially a Text-Based Fire Emblem game; it runs calculations and rolls dice and has all sorts of Goodies. However, I have hit a block to the tune of
#ifndef ITEM_H #define ITEM_H class Item {
[Code]....
Up Until I called up a Sword object, it worked fine. But when I compiled it, I got an Undefined Reference to Item::Item() error in Line 8 of Weapon.cpp.
Everything seems to be in order and I know my code still has mistakes. I'm just trying to get it to compile and it won't allow it. I've narrowed it down to when I call the functions in main but beyond that I have no clue.
#include <iostream> #include <cstring> using namespace std; void getSize(int num); void getSpace(int num, int ptr); void inputData(); void printData(); void destroy(); const int BIG_NUMBER = 100;
//pa4.cpp wirtten by Syd Frederick #include<iostream> #include<string> #include<fstream>
[Code].....
When compiling I'm getting a strange error that says :
/tmp/ccdt0Bf9.o: In function `main': pa4.cpp:(.text+0x1c): undefined reference to `synopsis()' pa4.cpp:(.text+0x1e7): undefined reference to `execute(std::basic_string<char, std::char_traits<char>, std::allocator<char> >)' collect2: ld returned 1 exit status
I don't understand how memcpy can't be there, it's been standard for 40 years. And I'm not using memcpy in my code, it's likely coming from one of the STL containers I use.
I've been reading about libraries; How to make them, how to use them, the different types of libraries, etc..
When using a shared library, does the program require that library to be installed on the computer after the program has been compiled into an .exe?
Ie.. if somebody downloaded a "Helloworld.exe" that I had compiled on my computer using a shared library (that wasn't part of a standard operating system), would they also need that shared library on their computer for the program to run without errors?
and for Static Libraries, when I compile a program using a static library, does it include in the final binary only the functions of the library that are actually used, or does the compiler add in the entire library?
trying to practice the object-oriented part of it by converting my java programs into c++. I believe I understand the concepts of a header file and declaring the functions in the .cpp files. I keep getting this "Undefined reference to NamedStorm::NamedStorm()" error.
NamedStorm.h #ifndef NAMEDSTORM_H #define NAMEDSTORM_H #include <string> #include <iostream> // NEVER use using namespce in header, use std instead. using std::string;
vijay13@ubuntu:~/Downloads$ g++ -o test test.cpp -I /home/vijay13/Downloads/OGDF-snapshot/include/
I am getting following error:
vijay13@ubuntu:~/Downloads$ g++ -o test test.cpp -I /home/vijay13/Downloads/OGDF-snapshot/include/ /tmp/ccPE8nCu.o: In function `main': test.cpp:(.text+0x26): undefined reference to `ogdf::Graph::Graph()' ...................... so on
