There seems to be an issue with the system readline utility which prevents Rubies installed by rvm from being compiled. A possible fix to this is to install your own version of readline.
Errors in the make log:
readline.c: In function ‘username_completion_proc_call’: readline.c:730: error: ‘username_completion_function’ undeclared (first use in this function) readline.c:730: error: (Each undeclared identifier is reported only once readline.c:730: error: for each function it appears in.) make: *** [readline.o] Error 1
Compile and install your own readline:
curl -O ftp://ftp.gnu.org/gnu/readline/readline-6.1.tar.gz tar xzvf readline-6.1.tar.gz cd readline-6.1 ./configure --prefix=/usr/local make sudo make install cd ..
First you have to remove Ruby versions you tried to compile before:
rvm remove 1.9.1
The following command with a reference to the newly installed newline should do the job:
rvm install 1.9.1 -C --with-readline-dir=/usr/local/