Is this bug in g++ /gcc-3.4.0 ?

Is this bug in g++ /gcc-3.4.0 ?

[yuki shimada]

[-- Attachment #1: Type: text/plain, Size: 597 bytes --]

Hollo!
I am Yuki Shimada.
This time , I had installed gcc-3.4.0 into my RedHat9.
And then,I had compiled "hello.cc" by using "g++". But cannot excute
"./a.out".   Compiler tells me a error.
(Incase of "hellp.c" complied by "gcc", "./a.out" can excute well.)

#1 error from g++
[yuki@localhost c++]$ g++ hello.cc
[yuki@localhost c++]$ ./a.out
./a.out: error while loading shared libraries: libstdc++.so.6: cannot
open shared object file: No such file or directory
[yuki@localhost c++]$
#2 my source code: see attachment of this mail.

Is this a bug ?
thank you.
epsoft@mint.ocn.ne.jp
Yuki Shimada


[-- Attachment #2: hello.cc --]
[-- Type: text/x-c++, Size: 331 bytes --]

//hello.cc
#include<iostream>
using namespace std;
int main(){
  cout<<"Hello !"<<endl;
  return 0;
};

//
//[yuki@localhost c++]$ g++ hello.cc
//[yuki@localhost c++]$ ./a.out
// ./a.out: error while loading shared libraries: libstdc++.so.6:
//  cannot open shared object file: No such file or directory
//[yuki@localhost c++]$
//

Re: Is this bug in g++ /gcc-3.4.0 ?

[llewelly]

yuki shimada <epsoft@mint.ocn.ne.jp> writes:

> Hollo!
> I am Yuki Shimada.
> This time , I had installed gcc-3.4.0 into my RedHat9.
> And then,I had compiled "hello.cc" by using "g++". But cannot excute
> "./a.out".   Compiler tells me a error.
> (Incase of "hellp.c" complied by "gcc", "./a.out" can excute well.)
> 
> #1 error from g++
> [yuki@localhost c++]$ g++ hello.cc
> [yuki@localhost c++]$ ./a.out
> ./a.out: error while loading shared libraries: libstdc++.so.6: cannot
> open shared object file: No such file or directory

You need to tell your linker-loader where to find libstdc++.so.6
. Use 'man ld.so' to read about the linker-loader.

By default, gcc will install libstdc++.so.6 into /usr/local/lib . If
    you configured gcc with --prefix, it  will be in $prefix/local/lib
    . If you don't know where libstdc++.so.6 is,

    $ find / -iname 'libstdc++.so.6' -print

    will tell you where it is.

Once you know where libstdc++.so.6 is, you can use ldconfig or
    LD_LIBRARY_PATH to tell the linker-loader where it is. Use 'man
    ldconfig' and 'man ld.so.conf' to read about ldconfig . Usually:

    # echo /usr/local/lib >> /etc/ld.so.conf
    # ldconfig

    (run as root)

    is correct. If libstdc++.so.6 is not in /usr/local/lib, replace
    '/usr/local/lib' with the directory containing libstdc++.so.6 .

To use LD_LIBRARY_PATH, set it as an environment variable:

    in bash:
    $ export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH

    in csh:
    > setenv LD_LIBRARY_PATH /usr/local/lib:$LD_LIBRARY_PATH

    Again, if libstdc++.so.6 is not in /usr/local/lib, replace it
    with the directory containing libstdc++.so.6 .
    

> #2 my source code: see attachment of this mail.

> Is this a bug ?

It's not a bug. Thank you for providing more information.

Re: Is this bug in g++ /gcc-3.4.0 ?

[Claudio Bley]

On Mon, May 10, 2004 at 10:01:41AM +0900, yuki shimada wrote:
> Hollo!

Konnichiha!

> I am Yuki Shimada.
> This time , I had installed gcc-3.4.0 into my RedHat9.
> And then,I had compiled "hello.cc" by using "g++". But cannot excute
> "./a.out".   Compiler tells me a error.

No, this is not a compiler error - the compiler is already done; the
program was compiled successfully.

> (Incase of "hellp.c" complied by "gcc", "./a.out" can excute well.)
> 
> #1 error from g++
> [yuki@localhost c++]$ g++ hello.cc
> [yuki@localhost c++]$ ./a.out
> ./a.out: error while loading shared libraries: libstdc++.so.6: cannot
> open shared object file: No such file or directory
> [yuki@localhost c++]$
> #2 my source code: see attachment of this mail.
> 
> Is this a bug ?

No, it's not a bug. It means the dynamic linker/loader (ld.so) hasn't found the
dynamic library it was looking for (libstdc++.so.6).

Just read the friendly `ld.so' man page (man ld.so) also avialable online; 
e.g. here:

http://unixhelp.ed.ac.uk/CGI/man-cgi?ld.so+8

in order to set it up that it can find the libraries where you installed them.

--
Claudio

Re: Is this bug in g++ /gcc-3.4.0 #3?

[llewelly]

I cc'd this to the gcc-help list because someone else there may either
    have a suggestion, or may have the same problem.

yuki shimada <epsoft@mint.ocn.ne.jp> writes:

> Dear person
> I am Yuki Shimada.
> Thank you for your helpping me.
> I had tried 
> 
> 1) I can find "libstdc++.so.6" is in "/usr/local/lib/libstdc++.so.6"
>    for example, I can read following list.
>      libstdc++.so
>      libstdc++.so.6
>      libstdc++.so.6.0.0
> 
> (  "find / -iname 'libstdc++.so.6' -print" takes very long time in my
> cpu .
>     So I did not complete it . ) 
> 
> 2) # echo /usr/local/lib >> /etc/ld.so.conf
>    # ldconfig
>    ---> after that,in "/etc/ld.so.conf",  command list are as followes.
> 
>       /usr/kerberos/lib
>       /usr/X11R6/lib
>       /usr/lib/sane
>       /usr/lib/qt-3.1/lib
>       /usr/local/lib     
> 
> 
> 3) in bash: I added some command like followings. Is this OK ?
> 
> # .bash_profile
> 
> # Get the aliases and functions
> if [ -f ~/.bashrc ]; then
> 	. ~/.bashrc
> fi
> 
> # User specific environment and startup programs
> 
> PATH=$PATH:$HOME/bin
> $export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
> BASH_ENV=$HOME/.bashrc
> USERNAME="root"

You don't need to do both LD_LIBRARY_PATH and ldconfig; only one or
    the other. LD_LIBRARY_PATH is per-user, ldconfig affects the whole
    machine. The cache updated by ldconfig is checked before
    LD_LIBRARY_PATH, however.

> 
> export USERNAME BASH_ENV PATH
> 
> 4) For about "csh", I have no knowledge about this.
>    Usually,I use "linux ". Must I set LD_LIBRARY_PATH in csh ?

You only need to set LD_LIBRARY_PATH for the shell you use. If you
    only use bash, don't worry about csh.

> 5) compilling and excuting result for my case;
> 
> [root@localhost c++]# g++ hello.cc
> [root@localhost c++]# ./a.out
> ./a.out: /lib/libgcc_s.so.1: version `GCC_3.3' not found (required by
> /usr/local/lib/libstdc++.so.6)
> [root@localhost c++]#

This is rather strange. I don't get this problem my fbsd or linux
    boxen. But I think the problem can be solved a same way: find
    libgcc_s.so.1, and then add the dir it is in to ldconfig.
    There are two caveats: you will have more than
    one libgcc_s.so.1 The one you want is probably in
    /usr/local/lib/gcc/i686-pc-linux-gnu/3.4.0/lib or in
    /usr/local/lib . You can find out for sure it is the right one by
    using:

    $ nm /usr/local/lib/libgcc_s.so.1 | grep GCC_3.4

    which should print something like:

    00000000 A GCC_3.4

The second caveat is that the directory containing the libgcc_s.so.1
    from gcc 3.4 *must* come first in both lists. So change your
    ld.so.conf to look like this:

    /usr/local/lib
    /lib
    /usr/lib
    /usr/kerberos/lib  
    /usr/X11R6/lib     
    /usr/lib/sane      
    /usr/lib/qt-3.1/lib

Finally run:

    # ldconfig

If this doesn't work, try LD_PRELOAD (which is also explained in the
    ld.so man page.) like this:

    $ export LD_PRELOAD=/usr/local/lib/libgcc_s.so.1



> 6) totally, I can not excute ./a.out still now.
>    Must I install "GCC_3.3" ?

GCC_3.3 is a symbol which libstdc++.so.6 requires. You could install
    gcc 3.3.3, but it wouldn't help; you still need to make ld.so find
    the *right* libgcc_s.so.1, and then, instead of having two, you'd
    have 3! So hold off on installing gcc 3.3.3 until you get 3.4
    working. 

> 7)Please help me!.