Xcode - configure: error: no acceptable C compiler found in $PATH

rebuilding a mac from scratch. Installed xcode and rvm then trying to install rubies but they are all giving me:

Error running ' ./configure --prefix=/Users/durrantm/.rvm/rubies/ruby-1.9.3-p125 
--enable-shared --disable-install-doc --with-libyaml 
--with-opt-dir=/Users/durrantm/.rvm/usr ', 
please read /Users/durrantm/.rvm/log/ruby-1.9.3-p125/configure.log
There has been an error while running configure. Halting the installation.
Michaels-MacBook-Air:~ durrantm$ 

The log has:

checking for gcc... no
checking for cc... no
checking for cl.exe... no
configure: error: in `/Users/durrantm/.rvm/src/ruby-1.9.2-p290':
configure: error: no acceptable C compiler found in $PATH

Do I need the gcc C compliler? How do I install it ?

The critical step is actually installing the Xcode command line tools after the download completes and Xcode is installed

After downloading and installing Xcode from the app store, you need to actually install the command line tools it provides.
To do this open Xcode, go to preferences then downloads. There is an "Install" link to add the command line tools.

Once this has been completed, make sure to re-open your terminal window.

Either you install Xcode from the App store or if you have a registered free developer account you can download the XCode command line tools from http://developer.apple.com/downloads

Once you have that installed you can go ahead and install your rubies with rvm.

rbenv install error :

configure: error: in `/tmp/ruby-build.20130911002344.31969/ruby-2.0.0-p0':
configure: error: no acceptable C compiler found in $PATH

...brought me here,

I am currently installing Ruby on rails, ruby through rbenv on a brand new Debian,

Original command is :

rbenv install 2.0.0-p0  

As a solution :

sudo apt-get install build-essential

Cheers !

[Sorry for the Xcode ppl]

Read rvm requirements it shows what you need to compile ruby.