Error while installing ruby version 2.2.5

when i do rvm install ruby-2.2.5 i am getting errors. any idea why?

M1620661:Wellness_service us044466$ rvm install ruby-2.2.5
ruby-2.2.5 - #removing src/ruby-2.2.5..
Searching for binary rubies, this might take some time.
Found remote file http://ift.tt/2fjbtZ2
Checking requirements for osx.
Certificates in '/usr/local/etc/openssl/cert.pem' are already up to date.
Requirements installation successful.
ruby-2.2.5 - #configure
ruby-2.2.5 - #download
ruby-2.2.5 - #validate archive
ruby-2.2.5 - #extract
ruby-2.2.5 - #validate binary
Libraries missing for ruby-2.2.5: /usr/local/opt/gmp/lib/libgmp.10.dylib. Refer to your system manual for installing libraries
Mounting remote ruby failed with status 10, trying to compile.
Checking requirements for osx.
Certificates in '/usr/local/etc/openssl/cert.pem' are already up to date.
Requirements installation successful.
Warning: found user selected compiler '/usr/local/opt/apple-gcc42/bin/gcc-4.2', this will suppress RVM auto detection mechanisms.
Installing Ruby from source to: /Users/us044466/.rvm/rubies/ruby-2.2.5, this may take a while depending on your cpu(s)...
ruby-2.2.5 - #downloading ruby-2.2.5, this may take a while depending on your connection...
ruby-2.2.5 - #extracting ruby-2.2.5 to /Users/us044466/.rvm/src/ruby-2.2.5....
ruby-2.2.5 - #configuring......
Error running './configure --prefix=/Users/us044466/.rvm/rubies/ruby-2.2.5 --with-opt-dir=/usr/local/opt/libyaml:/usr/local/opt/readline:/usr/local/opt/libksba:/usr/local/opt/openssl:/usr/local/opt/libyaml:/usr/local/opt/readline:/usr/local/opt/libksba:/usr/local/opt/openssl --disable-install-doc --enable-shared',
showing last 15 lines of /Users/us044466/.rvm/log/1478196378_ruby-2.2.5/configure.log
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking minix/config.h usability... no
checking minix/config.h presence... no
checking for minix/config.h... no
checking whether it is safe to define __EXTENSIONS__... yes
checking for cd using physical directory... cd -P
checking whether CFLAGS is valid... no
configure: error: something wrong with CFLAGS="-g -O2 "
There has been an error while running configure. Halting the installation.