Why wont this compile?

[Johnny2Bad]

Hi,
Well over the past few weeks this newbie has been very impressed over FreeBSD and wonders why he wasted years with M$ products. Your support has been wonderfull and the O/S rocks.

However being a programmer at heart I wanted to check out gcc++. So I made a file Hello.cpp

#include <iostream>

int main()
{
    cout << "Hello World\n";

    return 0;
}

the simplest program I could think of, which when compiled gives me...

/var/tmp//ccPEm5DG.o(.text+0x1e): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::size() const'
/var/tmp//ccPEm5DG.o(.text+0x69): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
/var/tmp//ccPEm5DG.o(.text+0xa7): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
/var/tmp//ccPEm5DG.o(.text+0xef): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
/var/tmp//ccPEm5DG.o(.text+0x13c): In function `main':
: undefined reference to `std::cout'
/var/tmp//ccPEm5DG.o(.text+0x141): 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*)'
/var/tmp//ccPEm5DG.o(.text+0x17d): In function `__static_initialization_and_destruction_0(int, int)':
: undefined reference to `std::ios_base::Init::Init()'
/var/tmp//ccPEm5DG.o(.text+0x1ce): In function `__tcf_0':
: undefined reference to `std::ios_base::Init::~Init()'
/var/tmp//ccPEm5DG.o(.eh_frame+0x11): undefined reference to `__gxx_personality_v0'
$ /var/tmp//ccPEm5DG.o(.text+0x1e): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::size() const'
/var/tmp//ccPEm5DG.o(.text+0x69): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
Syntax error: word unexpected (expecting ")")
/var/tmp//ccPEm5DG.o(.text+0xa7): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
$ : undefined reference to `std::string::size() const'
/var/tmp//ccPEm5DG.o(.text+0x69): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
/var/tmp//ccPEm5DG.o(.text+0xa7): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
: undefined reference to `std::string::operator[](unsigned int) const'
/var/tmp//ccPEm5DG.o(.text+0xef): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
> /var/tmp//ccPEm5DG.o(.text+0x69): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
Syntax error: "(" unexpected
$ : undefined reference to `std::string::operator[](unsigned int) const'
> /var/tmp//ccPEm5DG.o(.text+0xa7): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
Syntax error: word unexpected (expecting ")")
Syntax error: word unexpected (expecting ")")
$ : undefined reference to `std::string::operator[](unsigned int) const'
> /var/tmp//ccPEm5DG.o(.text+0xef): In function `std::__verify_grouping(char const*, unsigned int, std::string const&)':
Syntax error: word unexpected (expecting ")")
Syntax error: word unexpected (expecting ")")
$ : undefined reference to `std::string::operator[](unsigned int) const'
> /var/tmp//ccPEm5DG.o(.text+0x13c): In function `main':
Syntax error: word unexpected (expecting ")")
> : undefined reference to `std::cout'
main:
: undefined reference to `std::cout: not found
$ /var/tmp//ccPEm5DG.o(.text+0x141): In function `main':
Syntax error: word unexpected (expecting ")")
$ : 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*)'
> /var/tmp//ccPEm5DG.o(.text+0x17d): In function `__static_initialization_and_destruction_0(int, int)':
Syntax error: redirection unexpected
Syntax error: word unexpected (expecting ")")
$ : undefined reference to `std::ios_base::Init::Init()'
> /var/tmp//ccPEm5DG.o(.text+0x1ce): In function `__tcf_0':
> : undefined reference to `std::ios_base::Init::~Init()'
$ /var/tmp//ccPEm5DG.o(.eh_frame+0x11): undefined reference to `__gxx_personality_v0'

Can anyone explain why this is not working? Perhaps I should be posting this to a programming forum, however it is so simple I thought you guys would pickup where I was going wrong in seconds.

Thanking you in advance,
Jonathan.

[windependence]

It's been a while but I think you are missing some includes like stdio.h.

And yes, this should be in the programming forum.

-Tim

[18Googol2]

Originally Posted by Johnny2Bad

#include <iostream>

int main()
{
    cout << "Hello World\n";

    return 0;
}

".h" was missing. iostream ==> iostream.h

[ephemera]

looks like you were trying to compile it with 'gcc' instead of 'g++'.

change your program to:

//  test.cc  or test.cpp
#include <iostream>

int main()
{
    std::cout << "Hello World\n";

    return 0;
}

to compile:

$ g++ test.cc

[BSDfan666]

Or, instead.. do:

//  test.cc  or test.cpp
#include <iostream>

using namespace std;

int
main(void) {
    cout << "Hello World\n";
                            
    return 0;               
}

That we you don't need to add the std:: prefix..

Anyway, I don't understand why people use C++ instead of C.. it's so much cleaner.

[Nicolas]

Originally Posted by BSDfan666

Anyway, I don't understand why people use C++ instead of C.. it's so much cleaner.

Yes ... I agree with you ... Things are so simple in C ...

I tried the compilation and it works fine for me (FreeBSD 6.3) using std::cout.

On older versions, you may have to add libstd++ to link the software.

[ephemera]

people have different requirements IMO its not correct to discourage others from using c++ because of your personal (unsubstantiated) opinions.

freebsd has proper support for c++ and quite a few apps (outside the fbsd base system) use c++.

[Nicolas]

1) I don't discourage others ... only the ones who work with me
2) I do not want to start a troll pros/cons c++

I only said that I agree with BSDfan666.

I have spent 9 months debugging a huge C++ hugly code, because the language is too much complicated for novices.

C is far more simpler (powerless ? I do not think so)

I may speak about malloc/new, references, exceptions and so on...

"How C++ is like teenage sex:

1. It is on everyone's mind all the time.
2. Everyone talks about it all the time.
3. Everyone thinks everyone else is doing it.
4. Almost no one is really doing it.
5. The few who are doing it are: A. Doing it poorly. B. Sure it will be better next time. C. Not practising it safely."

[ephemera]

> I have spent 9 months debugging a huge C++ hugly code, because the language is too much complicated for novices.

yes i agree C++ is a complicated prog. language.

> "How C++ is like teenage sex: ... Not practising it safely."

i hope you didn't miss the context of that joke.
it was a toilet graffiti in the CS dept. of a college in Israel way back in 1993 (i suppose C++ must have been the over-hyped latest programming fad at the time).