Compile probs

[asm1]

please help, when i compile the following code i get errors not sure what they mean though. very new to Linux and C++

#include <iostream>
int main ()
{
  int localVar = 5;
  int * plocal = &localVar;
  int * pheap = new int;
  *pheap = 7;
  cout << &quot;localVar: &quot; << localVar << &quot;\n&quot;;
  cout << &quot;plocal: &quot; << plocal << &quot;\n&quot;;
  cout << &quot;pheap: &quot; << pheap <<&quot;\n&quot;;
  delete pheap;
  pheap = new int;
  *pheap = 9;
  cout << &quot;pheap: &quot; << pheap <<&quot;\n&quot;;
  delete pheap;
  return 0;
}

[tony@jstlinbox c]$ gcc ccode.cpp -o myoutputccode
ccode.cpp: In function `int main()':
ccode.cpp:11: `cout' undeclared (first use this function)
ccode.cpp:11: (Each undeclared identifier is reported only once for each
function it appears in.)
[tony@jstlinbox c]$

The tougher it gets the more you learn! The more you learn the tougher it gets!

 

[chipperMDW]

cout lives in namespace std.

Therefore, its full name is std::cout.

You can use this name every time you refer to it.

Or you can say "using std::cout" to bring the name into a scope.

Or, as the least preferable alternative, you can say "using namespace std;" at the beginning of your program.

 

[asm1]

thanks for that, now u mention it I actually remember reading it somewhere; I will have a mess

The tougher it gets the more you learn! The more you learn the tougher it gets!

 

[asm1]

i did this but i now get more errors and i can't see the problem. could i be compiling wrong or maybe the .cpp file extension wrong, i just dont know. i have put the alterd programme and errors below thx

//deleating pointers
//alocating and deleating pointers
#include <iostream>
using std::cout;
using std::endl;

int main ()
{
  int localVar = 5;
  int * plocal = &localVar;
  int * pheap = new int;
  *pheap = 7;
  cout << &quot;localVar: &quot; << localVar << endl;
  //cout << &quot;*plocal: &quot; << *plocal << endl;
  cout << &quot;*pheap: &quot; << *pheap << endl;
  delete pheap;
  pheap = new int;
  *pheap = 9;
  cout << &quot;*pheap: &quot; << *pheap << endl;
  delete pheap;
  cout << endl;
  return 0;
}

and the erros are

[tony@jstlinbox tony]$ cd ./c
[tony@jstlinbox c]$ gcc ccode.cpp -o outccode
/tmp/ccvV43TY.o(.text+0x23): In function `main':
: undefined reference to `operator new(unsigned)'
/tmp/ccvV43TY.o(.text+0x3a): In function `main':
: undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)'
/tmp/ccvV43TY.o(.text+0x4d): In function `main':
: undefined reference to `std::cout'
/tmp/ccvV43TY.o(.text+0x52): In function `main':
: undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
/tmp/ccvV43TY.o(.text+0x5b): In function `main':
: undefined reference to `std::basic_ostream<char, std::char_traits<char> >::operator<<(int)'
/tmp/ccvV43TY.o(.text+0x64): In function `main':
: undefined reference to `std::basic_ostream<char, std::char_traits<char> >::operator<<(std::basic_ostream<char,

they actually go on a lot further

The tougher it gets the more you learn! The more you learn the tougher it gets!

 

[asm1]

ok i have taken the programme back to an hello world and this is what i get

//deleating pointers
//alocating and deleating pointers

#include <iostream>
using std::cout;
//using std::endl;

int main ()
{
  /*

	int localVar = 5;
  int * plocal = &localVar;
  int * pheap = new int;
  *pheap = 7;
  cout << &quot;localVar: &quot; << localVar << endl;
  //cout << &quot;*plocal: &quot; << *plocal << endl;
  cout << &quot;*pheap: &quot; << *pheap << endl;
  delete pheap;
  pheap = new int;
  *pheap = 9;
  cout << &quot;*pheap: &quot; << *pheap << endl;
  delete pheap;   
       
	*/
	cout << &quot;Hello world&quot;;
  //cout << endl;
  return 0;
}

errors

[tony@jstlinbox c]$
[tony@jstlinbox c]$ gcc hello.cpp -o outhello
/tmp/ccTKztTm.o(.text+0x19): In function `main':
: undefined reference to `std::cout'
/tmp/ccTKztTm.o(.text+0x1e): In function `main':
: undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std:perator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
/tmp/ccTKztTm.o(.text+0x4a): In function `__static_initialization_and_destruction_0(int, int)':
: undefined reference to `std::ios_base::Init::Init[in-charge]()'
/tmp/ccTKztTm.o(.text+0x79): In function `__tcf_0':
: undefined reference to `std::ios_base::Init::~Init [in-charge]()'
/tmp/ccTKztTm.o(.eh_frame+0x11): undefined reference to `__gxx_personality_v0'
collect2: ld returned 1 exit status
[tony@jstlinbox c]$

The tougher it gets the more you learn! The more you learn the tougher it gets!

 

[chipperMDW]

You're trying to use gcc (the C compiler frontend) to compile a C++ program.

You want to be using g++ (the C++ compiler frontend).

 

[jstreich]

Also, you may want to include the whole namespace if your just getting started with the language, as there might a lot of things in the name space you'll need... You can always pare the namespace down to what you used after it's ready for realse.

 

[asm1]

Thanks guys, feel a bit silly now I have been messing for two days.


The tougher it gets the more you learn! The more you learn the tougher it gets!