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I'm a linux virgin and have only been programming c++ for 2 weeks, so please bear with me.

I'm trying to set the default g++ to 4.7.2 which I'm told by my host is installed (I'm also told that c++11 is also installed); however, neither of us know how to set the default g++ to 4.7.2 because g++ --version gives

g++ (GCC) 4.1.2 20080704 (Red Hat 4.1.2-54)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO

I tried these sudo commands here, but I just found out that they don't work because CentOS uses yum.

How can I set the default g++ to 4.7.2 (if it's even installed) on CentOS 5.9?

share|improve this question
The stock version of gcc in the CentOS repos is 4.1.2 (with the option of 4.4). Have you tried this answer to "Install gcc 4.7 on CentOS"? – Reed Kraft-Murphy Feb 3 '13 at 22:32
@ReedKraft-Murphy sorry for deleting that last post out from under you. I saw your answer too late. when i do the yum --enablerepo=testing-devtools-6 install devtoolset-1.0-gcc line, it gives Error getting repository data for testing-devtools-6, repository not found. Thank you for helping! (I'm going to ask this in a formal question) – user31705 Feb 3 '13 at 22:34
No worries. Since you're on CentOS 5.x, rather than 6.x, I'm guessing you'll need to say yum --enablerepo=testing-devtools-5 ... rather than testing-devtools-6, but I'll happily take this to a formal question :) – Reed Kraft-Murphy Feb 3 '13 at 22:41
@ReedKraft-Murphy thank you reed! i've moved it here unix.stackexchange.com/questions/63587/… – user31705 Feb 3 '13 at 22:42
up vote 0 down vote accepted

You need to set the CXX environment variable. For example, export CXX="/usr/bin/g++-4.7" . And CC is the one that controls the C compiler.

share|improve this answer
Thank-you for looking! I tried that, and I'm still getting the same result for --version. I tried executing /usr/bin/g++-4.7. Does that mean it's not even installed? – user31705 Feb 3 '13 at 21:42
Well, the path in my answer was only an example. If you don't know if/where the newer g++ is, it's gonna be more difficult. – schaiba Feb 3 '13 at 21:46

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