g++ compile error

Question

I'm a newbie in Ubuntu. I tried to compile a simple "Hello World!" c++ code in Ubuntu 11.04, with that code (in terminal):

gcc -Wall -W -Werror tex.cpp -o tex.

but compiler returned a lot of errors :

/tmp/ccL8c1p8.o: In function `main':
tex.cpp:(.text+0xa): undefined reference to `std::cout'
tex.cpp:(.text+0xf): 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/ccL8c1p8.o: In function `__static_initialization_and_destruction_0(int, int)':
tex.cpp:(.text+0x3d): undefined reference to `std::ios_base::Init::Init()'
tex.cpp:(.text+0x42): undefined reference to `std::ios_base::Init::~Init()'
collect2: ld returned 1 exit status
mohrd@mio:~$ gcc -Wall -W -Werror tex.cpp -o tex.
/tmp/ccEke5JP.o: In function `main':
tex.cpp:(.text+0xa): undefined reference to `std::cout'
tex.cpp:(.text+0xf): 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/ccEke5JP.o: In function `__static_initialization_and_destruction_0(int, int)':
tex.cpp:(.text+0x3d): undefined reference to `std::ios_base::Init::Init()'
tex.cpp:(.text+0x42): undefined reference to `std::ios_base::Init::~Init()'
collect2: ld returned 1 exit status

simple code :

#include <algorithm>
#include <iostream>
using namespace std;

int main ()
{
  std::cout << "Hello World!";
  return 0;
}

Why? and what should I do???

many thanks ...

You say g++ in the title, but use gcc in the body of the message - so which is it? — , Jul 27 '11 at 15:36
I'm newbie,really. and i don't know about difference between gcc and g++! — kio, Jul 27 '11 at 20:12

score 34 · Accepted Answer · answered Jul 27 '11 at 15:35

34

You need to use the g++ (or c++) command to compile your program, using "gcc" will compile it as c++ due to the .cpp extension but not link in the required c++ libraries.

answered Jul 27 '11 at 15:35

jcoder

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5

Or add `-lstdc++` to the command line to link the standard C++ libraries. But compiling with `g++` is the better solution. – Adam Rosenfield Jul 27 '11 at 15:37

score 6 · Answer 2 · answered Jul 27 '11 at 15:37

6

Use g++ instead of gcc for compiling C++ code:

g++ -Wall -W -Werror tex.cpp -o tex

gcc does not link stdc++ library by default which is required for your code.

answered Jul 27 '11 at 15:37

AmokHuginnsson

1,174
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score 4 · Answer 3 · answered Jul 27 '11 at 15:36

4

Use the g++ command instead of gcc.

answered Jul 27 '11 at 15:36

highlycaffeinated

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Paul · Answer 4 · 2011-07-27T15:56:54.167

1

Try:

g++ -Wall hello.cpp -o hello

Beacuse you are trying to compile C++ code, not C code!

-Wall means Warning ALL, so you'll already see all the warnings

Also, name your programs and source files meaningfully!

LE: of course -Werror remains your choice

LE2: no need of #include <algorithm> in your code, so you can remove it!

edited Jul 27 '11 at 15:56

answered Jul 27 '11 at 15:38

Paul

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score -1 · Answer 5 · answered Apr 30 '21 at 00:50

-1

I was getting the same error for creating a giant arrary (50005) items. Be careful

answered Apr 30 '21 at 00:50

nivalderramas

79
9

g++ compile error

5 Answers5

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