I recently upgraded to OS X Yosemite and ran brew install. As a result, my rails setup failed. In the past, re-install ruby worked. However, in this case, when I re-installed it I ran into this issue
BUILD FAILED (OS X 10.10 using ruby-build 20141016) Inspect or clean up the working tree at /var/folders/93/p8zdbgn14j99_l5x7js97zkm0000gn/T/ruby-build.20141020234934.40511 Results logged to /var/folders/93/p8zdbgn14j99_l5x7js97zkm0000gn/T/ruby-build.20141020234934.40511.log Last 10 log lines: 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=" -O3 -Wno-error=shorten-64-to-32 " make: *** No targets specified and no makefile found. Stop.
To fix the issue, I had to reinstall ruby with the following flags:
RUBY_CONFIGURE_OPTS="--without-gcc --disable-install-rdoc" rbenv install 2.1.3