Re: Class and C++

Altera_Forum · ‎03-28-2006

Hi everyone,

I'm brand new developer with NiosII and C++, and I'm experiencing some problems with NiosII IDE, expecially in building application in C++.

I created a classe called "thread". I wrote 2 files, an simple header file thread.h and a cpp file, thread.cpp.

During building, I receive this error message:

Compiling thread.cpp...

../thread.cpp:10: error: new types may not be defined in a return type

../thread.cpp:10: error: return type specification for constructor invalid

../thread.cpp: In member function `void thread::begin()':

../thread.cpp:16: error: `TIMER_BASE' undeclared (first use this function)

../thread.cpp:16: error: (Each undeclared identifier is reported only once for each function it appears in.)

../thread.cpp:16: error: expected primary-expression before ')' token

../thread.cpp: In member function `void thread::end()':

../thread.cpp:26: error: `TIMER_BASE' undeclared (first use this function)

make: *** [obj/thread.o] Error 1

code listed below: thread.h

# ifndef _THREAD_H_# define _THREAD_H_

# define TIMEOUT# define TIME# include "altera_avalon_timer_regs.h"

class thread

{

public:

int state;

int ticks;

thread();

~thread();

void begin();

void end();

int getState();

}

# endif //_THREAD_H_

code listed below: thread.cpp

# include <system.h>

# include "thread.h"# include "altera_avalon_timer_regs.h"

void thread::thread() {}

void thread::~thread() {}

void thread::begin(void)

{

// inizializzazione timer e partenza

IOWR_ALTERA_AVALON_TIMER_PERIODL(TIMER_BASE, TIME);

IOWR_ALTERA_AVALON_TIMER_PERIODH(TIMER_BASE, 0x00);

IOWR_ALTERA_AVALON_TIMER_CONTROL(TIMER_BASE, 0x07);

state = 1;

ticks = 0;

}

void thread::end(void)

{

// terminazione timer

IOWR_ALTERA_AVALON_TIMER_CONTROL(TIMER_BASE, 0x0b);

state = 0;

}

int thread::getState(void)

{

return state;

}

So, I don't understand where are the problems:

1. What does it mean "new types may not be defined in a return type"?

2. Why TIMER_BASE is unknown, although is defined in <system.h> header file?

Someone can help me? Thanks.

G.

Altera_Forum · ‎03-28-2006

--- Quote Start ---

originally posted by g.sanzi@Mar 28 2006, 10:03 AM

hi everyone,

i'm brand new developer with niosii and c++, and i'm experiencing some problems with niosii ide, expecially in building application in c++.

i created a classe called "thread". i wrote 2 files, an simple header file thread.h and a cpp file, thread.cpp.

during building, i receive this error message:

compiling thread.cpp...

../thread.cpp:10: error: new types may not be defined in a return type

../thread.cpp:10: error: return type specification for constructor invalid

../thread.cpp: in member function `void thread::begin()':

../thread.cpp:16: error: `timer_base' undeclared (first use this function)

../thread.cpp:16: error: (each undeclared identifier is reported only once for each function it appears in.)

../thread.cpp:16: error: expected primary-expression before ')' token

../thread.cpp: in member function `void thread::end()':

../thread.cpp:26: error: `timer_base' undeclared (first use this function)

make: *** [obj/thread.o] error 1

Code listed below: thread.h[/b]

# ifndef _THREAD_H_# define _THREAD_H_

# define TIMEOUT# define TIME# include "altera_avalon_timer_regs.h"

class thread

{

public:

int state;

int ticks;

thread();

~thread();

void begin();

void end();

int getState();

}

# endif //_THREAD_H_

code listed below: thread.cpp

# include <system.h>

# include "thread.h"# include "altera_avalon_timer_regs.h"

void thread::thread() {}

void thread::~thread() {}

void thread::begin(void)

{

// inizializzazione timer e partenza

IOWR_ALTERA_AVALON_TIMER_PERIODL(TIMER_BASE, TIME);

IOWR_ALTERA_AVALON_TIMER_PERIODH(TIMER_BASE, 0x00);

IOWR_ALTERA_AVALON_TIMER_CONTROL(TIMER_BASE, 0x07);

state = 1;

ticks = 0;

}

void thread::end(void)

{

// terminazione timer

IOWR_ALTERA_AVALON_TIMER_CONTROL(TIMER_BASE, 0x0b);

state = 0;

}

int thread::getState(void)

{

return state;

}

So, I don't understand where are the problems:

1. What does it mean "new types may not be defined in a return type"?

2. Why TIMER_BASE is unknown, although is defined in <system.h> header file?

Someone can help me? Thanks.

G.

<div align='right'><{post_snapback}> (index.php?act=findpost&pid=13853)

--- Quote End ---

[/b]

--- Quote End ---

i solved myself: it's only for a fucked ";" after class declaration!!!!!!!

Altera_Forum · ‎07-27-2010

hello,

I cannot define a class using Nios II IDE environment! the class is defined in basicOCR.h as follow:

--- Quote Start ---

class basicOCR{

public:

float classify(IplImage* img,int showResult);

basicOCR ();

void test();

private:

char file_path[255];

int train_samples;

int classes;

CvMat* trainData;

CvMat* trainClasses;

int size;

static const int K=10;

CvKNearest *knn;

void getData();

void train();

};

--- Quote End ---

Although "Support C++" is activated, errors occur:

--- Quote Start ---

../basicOCR.h: At top level:

../basicOCR.h:25: error: syntax error before "basicOCR"

../basicOCR.h:25: error: syntax error before '{' token

../basicOCR.h:30: error: syntax error before ':' token

--- Quote End ---

any ideas ? thanks

Altera_Forum · ‎07-28-2010

Is your .h file included from a .c file or a .cpp? I think it needs to be .cpp so that Eclipse compiles it in C++ mode.

Altera_Forum · ‎07-28-2010

Actually it did (basicOCR.cpp)

Altera_Forum · ‎07-29-2010

Hmmm I don't think that you need to rename the header files to .hpp to make the compiler stay in C++ mode.

The include statement isn't inside an extern "C" {} block by any chance?

Altera_Forum · ‎07-29-2010

renaming the header files came out with nothing!

the basicOCR.cpp includes the header file as (#include "basicOCR.hpp"), but does this have to do with the header file itself?

I'm sorry if I couldn't get your last reply!

Altera_Forum · ‎07-29-2010

Be sure the class declaration in the header file ends with a ;, like:


class abc
{
//.....
};

Bill