Occasionally, I get one error message and many warnings.
The error message is utterly useless:

"Error      error: ld returned 1 exit status      collect2.exe"

The verbose build output is attached. 

My code is huge, so I am not going to waste your (or my) time trying to attach it. Instead, I want to understand:

1) What causes this message?
2) How do I diagnose that cause? I.E. What do I look for that will help me understand the cause?
3) How do I fix this problem?

My verbose output is attached. What indicates "linked incorrectly."? I am hunting through over 500 lines of output. What is the pattern I s/b searching for?

Tim,

I am delighted that the error looks fairly clear to you, but I am old and getting senile and it's not clear to me. The two lines that say:

DualMotorL298N.h:undefined reference to `vtable for DualMotorL298N
DualMotorL298N.h:undefined reference to `vtable for DualMotorL298N

Suggest that DualMotorl298N is not implementing all of the abstract methods from its parents, but I have checked carefully and all abstracts have a corresponding concrete in the DualMotor class. 

So why am I getting an "undefined reference" in a .h file?

Tim,

A couple points of clarification:
1) I exceeded the UNO memory so I switched to a MEGA and have plenty of memory.

2) I did copy some of my libraries to the libraries folder and that was the beginning of some of my problems. I built the library properties file but kind of punted on the keywords.txt file. Am I making a bad assumption that the keywords.txt file is not a key element in the compile?

When I copied my classes to the Libraries folder, the compiler can't find them any more. I add them, refresh the list, check again but the compiler keeps stopping when it thinks it can't find the .h file for that class. So I have moved most of my classes into the same folder as the .ino file.

The verbose output is in the project code file (see buildoutput.txt). I am still stuck trying to understand what the compiler is telling me. Its diagnostic output feels like the kind stuff somebody would write if they never had to use their own code. The Warnings just say "Warning - but I am not going to tell you what the problem is... I am just going to say "Warning" and you can guess... if you're lucky..."


I have attached the entire project code. The Library zips down to about 2MB, so I cannot send it via this interface. Ideas or suggestions?

Thanks again for your help. I am trying to do a really good job with the architecture of this code, but the compiler seems to want to fight with me every step of the way!

I bob Visual Micro uses the same process as Arduino so you won't have any problems getting help with this type of request on the arduino.cc forum.

I think the easiest solution will be to grab the verbose output, put in a .bat file then edit or add to it as required.

Hi Bob,

Yes windows .bat files can be run from the command prompt. If they output to file then you can simply double click and run from windows explorer.

For windows explorer, if I recall, you can also add the "Pause" command at the end of the bat to prevent the window from closing after the .bat runs.

Hi

Best place for questions about avr/gcc tools and object files is probably the arduino.cc forum.

Sorry I am not an expert with gcc

Ignore the quote they always appear in all avr/gcc outputs.

It doesn't build it is missing BJMotionDetector.h

Hi,

I noticed you have posted a visual micro verbose output with your question in the arduino.cc forum. That will just cause confusion. My suggestion was to build using the Arduino IDE to confirm the same error then post the verbose output from the Arduino IDE in the Arduino forum. If you don't work that way you won't get any help from the arduino crowd and it is a main point about why Visual Micro remains compatible with the Arduino IDE


So I comment a missing file and it then fails with this error:-

DualMotorRomeo.h:undefined reference to `vtable for DualMotorRomeo
 

Double clicking the error takes me to the following line which appears to be expecting the static struct defined in BJRobotOptions.h called BJRobotOptions::Settings to be passed by ref. 

DualMotorRomeo.h

	BJRobotOptions::Settings *settings;

//	Constructor
	DualMotorRomeo(BJRobotOptions::Settings *s) : settings(s), GenericDualMotor(this, MT_ROMEO) {
		_leftMotion = settings->motorPins.leftMotion;
		_leftSpeed = settings->motorPins.leftSpeed;
		_leftFlip = settings->motorPins.leftFlip;
		_rightMotion = settings->motorPins.rightMotion;
		_rightSpeed = settings->motorPins.rightSpeed;
		_rightFlip = settings->motorPins.rightFlip;
		};
 

GenericMotorDual.h

class MotorDefinition;

class GenericDualMotor : public PropulsionSystem {
protected:
	bool validated;
	GenericDualMotor *motor;

public:
	MotorDefinition *leftMotor;
	MotorDefinition *rightMotor;

	//	Constructor
	GenericDualMotor(GenericDualMotor *m, int mType)
		: motor(m), PropulsionSystem(PT_DUAL_MOTOR, mType) {
		validated = false;
	};

	//	Destructor
	virtual ~GenericDualMotor() {}; 

BJRobotOptions.h

#include "BJRobotSettings.h"

class BJRobotOptions {
public:

#if MOTOR_TYPE == MT_L298N
	static struct MT_L298N_PINS {
		int MotorType = MOTOR_TYPE;
		int IN1 = MT_L298N_IN1;
		int IN2 = MT_L298N_IN2;
		int ENA = MT_L298N_ENA;
		bool FLIPA = MT_L298N_FLIPA;
		int IN3 = MT_L298N_IN3;
		int IN4 = MT_L298N_IN4;
		int ENB = MT_L298N_ENB;
		bool FLIPB = MT_L298N_FLIPB;
	} motor_L298N;
#elif MOTOR_TYPE == MT_L9110
	static struct MT_L9110_PINS {
		int MotorType = MOTOR_TYPE;
		int PWMA = MT_L9110_PWMA;
		int DIRA = MT_L9110_DIRA;
		int FLIPA = MT_L9110_FLIPA;
		int PWMB = MT_L9110_PWMB;
		int DIRB = MT_L9110_DIRB;
		int FLIPB = MT_L9110_FLIPB;
	} motor_L9110;
#elif MOTOR_TYPE == MT_ROMEO
	static struct MT_ROMEO_PINS {
		int MotorType = MOTOR_TYPE;
		int leftMotion = MT_ROMEO_LEFTMOTION;
		int leftSpeed = MT_ROMEO_LEFTSPEED;
		bool leftFlip = MT_ROMEO_LEFTFLIP;
		int rightMotion = MT_ROMEO_RIGHT_MOTION;
		int rightSpeed = MT_ROMEO_RIGHT_SPEED;
		bool rightFlip = MT_ROMEO_RIGHT_FLIP;
	} motor_ROMEO;
#elif MOTOR_TYPE == MT_ZUMO
	static struct MT_ZUMO_PINS {
		int MotorType = MOTOR_TYPE;
		int leftMotion = MT_ZUMO_LEFTMOTION;
		int leftSpeed = MT_ZUMO_LEFTSPEED;
		bool leftFlip = MT_ZUMO_LEFTFLIP;
		int rightMotion = MT_ZUMO_RIGHT_MOTION;
		int rightSpeed = MT_ZUMO_RIGHT_SPEED;
		bool rightFlip = MT_ZUMO_RIGHT_FLIP;
	} motor_ZUMO;
#else
	assert(false);
#endif

	//	Destructor
	~BJRobotOptions() {};


	//	PIN SETTINGS:
	//
	//	Red signals obstacle very close
	//	Yellow signals obstacle nearby but not up close and personal...yet
	//	Green signals no obstacles nearby
	//	Blue signals command(s) being executed which indicate that the robot is moving.
	//
	//	The associated ranges for these signals can be specified with the pin settings:
	struct ObstaclePinSetting {
		int pin;
		int distance;	// in CM
	};

	static struct ObstaclePinSettings {
		ObstaclePinSetting redPin;
		ObstaclePinSetting yellowPin;
		ObstaclePinSetting greenPin;
		ObstaclePinSetting bluePin;
	} obstaclePinSettings;

	//	One ring to rule them all... this struct contains ALL settings values
	struct Settings {
		int CompassType;
		int OutputOptions;
		ObstaclePinSettings *pins;
#if MOTOR_TYPE == MT_L298N
		struct MT_L298N_PINS motorPins;
#elif MOTOR_TYPE == MT_L9110
		struct MT_L9110_PINS motorPins;
#elif MOTOR_TYPE == MT_ROMEO
		struct MT_ROMEO_PINS motorPins;
#elif MOTOR_TYPE == MT_ZUMO
		struct MT_ZUMO_PINS motorPins;
#endif
	} settings;

	bool init(Settings *settings);

	const char* getMotorType(int mType);
	const char* getCompassType(int cType);

private:
	bool _initialized = false;
};

#endif


 

In all of this you have some static, some objects and inheritance.

I have explained previously that I need to keep this forum for support of the plugin for Visual Studio and Atmel Studio. I don't make money from selling hardware and am one person when the arduino forum is many people. Therefore for problems in code, to prevent me from being drowned with unrelated requests, I ask that help with code is found from the many other places on the web.

These other "places" for support will not be as forgiving as me. Posting a verbose output on it's own without showing or giving overview of the code, as I have done above, will not allow people to help you.

You should make a cut down test of what you are trying to achiever. You create BJOptions/settings in the .ino. Later you try to use the settings in a call to a method in a semi-static inherited environment. I don't see how any of your previous reports about this show the issue.

In addition to making better reports I also ask that when you provide examples that you have tested them yourself and informed helpers like myself which libraries need to be installed. It needed TimerOne

Quote:


Do you mean the compile problem you have reported shows when BJMotionDetector.h is commented out? If so then I agree with you.

Lastly I have said before that my knowledge it limited however I see you are expecting a constructor in a class to be used in static way and the constructor is doing some complex stuff with objects and inheritance. I don't know when you expect things to be initialized in this usage? When do you create the non-static objects?