1

Could someone please tell me a sure-way of getting g++ and g++4.7 on to my Ubuntu? I have spent the whole day trying lots of sudo apt-get and nothing has worked.

When compiling from the IDE I am missing g++ as I get the compiler error:

“make[2]: g++: Command not found”

If I do:

sudo update-alternatives --config g++

it returns:

update-alternatives: error: no alternatives for g++.

If I do:

g++ --version

it returns:

The program 'g++' can be found in the following packages:
 * g++
 * pentium-builder
Try: sudo apt-get install <selected package>

I already have gcc 4.8 but I need g++ 4.7 (and possibly 4.8 if someone could advise me how I can download that?) because my code (which I did manage to compile with 4.7 earlier) is giving a compiler bug internal error.

(I havent been able to list every command I tried as there's been so many). There must be a way which definitely works

EDIT:

Have run to get g++ 4.6 so now when I call the g++ --version I get 4.6 showing. I then tried sudo apt-get install g++-4.7 to "upgrade" to 4.7 but this seemed to lose my g++ because I couldnt do g++ --version afterwards. I reverted back to 4.6. How can I upgrade to 4.7 and I really need to know how to get g++ 4.8?

Improve this question
1
  • I have- which is how I originally found a g++ internal compiler error... which is what lead me to try and update to 4.8 (which now seems to have made my g++ disappear).
    – mezamorphic
    Nov 3, 2013 at 23:40

1 Answer 1

Reset to default
3

If I have to guess, I will say that somehow your g++ symbolic link got damaged. A reinstallation of the g++ package should fix the issue:

sudo apt-get --reinstall install g++

Or, if you like doing things manually (you should try the above method first), you could:

If you have 4.6

sudo ln -i -s /usr/bin/g++-4.6 /usr/bin/g++

If you have 4.7

sudo ln -i -s /usr/bin/g++-4.7 /usr/bin/g++

If you have 4.8

sudo ln -i -s /usr/bin/g++-4.8 /usr/bin/g++
Improve this answer
9
  • I will try the above now. I'd like to say thanks for continuing to help me- I really appreciate it.
    – mezamorphic
    Nov 3, 2013 at 23:48
  • OK I tried the --reinstall command you wrote above and it worked to the extent that if I do g++ --version it now says I am using 4.6. WHen I try to see all versions I have via sudo update-alternatives --config g++ it doesn't work, still says no alternatives. Would you be able to tell me how I can install g++ 4.8 because I think I require this to get around the internal compiler bug I discovered when using 4.7?
    – mezamorphic
    Nov 3, 2013 at 23:51
  • Worked out whats happening. When I go to install g++4.7 I seem to lose my g++ altogether. I use: sudo apt-get install g++-4.7 after your command...
    – mezamorphic
    Nov 4, 2013 at 0:04
  • 1
    As far as I know, the gcc-4.x and g++-4.x packages do not automatically add themselves to the update-alternatives mechanism. You can add them manually using update-alternatives --install as described here --> ubuntuforums.org/… however I'm reluctant to post that as an answer since there are likely good reasons why that is not done by default. Or you can create the appropriate symlinks manually as described by @Braiam .
    – steeldriver
    Nov 4, 2013 at 0:06
  • @steeldriver you beat it to me :(
    – Braiam
    Nov 4, 2013 at 0:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.