unable to install compass

Question

Last week I made an update in cygwin because of the bash "vulnerable problem".
After that I couldn't compile sass anymore.
I tried to reinstall ruby, after some install fails and reinstalling cygwin I installed it and updated with
"gem update --system"
it run, but when I tried to install compass I got following message:

> /usr/bin/ruby.exe -r ./siteconf20141006-7856-1td7wzb.rb extconf.rb 
> checking for ffi.h... *** extconf.rb failed ***  Could not create
> Makefile due to some reason, probably lack of necessary  libraries
> and/or headers. Check the mkmf.log file for more details. You may 
> need configuration options.
> 
> Provided configuration options: 
> --with-opt-dir 
> --without-opt-dir 
> --with-opt-include 
> --without-opt-include=${opt-dir}/include 
> --with-opt-lib 
> --without-opt-lib=${opt-dir}/lib 
> --with-make-prog 
> --without-make-prog 
> --srcdir=. 
> --curdir 
> --ruby=/usr/bin/ruby 
> --with-ffi_c-dir 
> --without-ffi_c-dir 
> --with-ffi_c-include 
> --without-ffi_c-include=${ffi_c-dir}/include 
> --with-ffi_c-lib 
> --without-ffi_c-lib=${ffi_c-dir}/ 
> --with-libffi-config 
> --without-libffi-config 
> --with-pkg-config 
> --without-pkg-config  /usr/share/ruby/2.0.0/mkmf.rb:434:in `try_do': The compiler failed to generate an executable file. (RuntimeError) 
> You have to install development tools first.  from
> /usr/share/ruby/2.0.0/mkmf.rb:565:in `try_cpp'  from
> /usr/share/ruby/2.0.0/mkmf.rb:1044:in `block in have_header'  from
> /usr/share/ruby/2.0.0/mkmf.rb:895:in `block in checking_for'  from
> /usr/share/ruby/2.0.0/mkmf.rb:340:in `block (2 levels) in postpone' 
> from /usr/share/ruby/2.0.0/mkmf.rb:310:in `open'  from
> /usr/share/ruby/2.0.0/mkmf.rb:340:in `block in postpone'  from
> /usr/share/ruby/2.0.0/mkmf.rb:310:in `open'  from
> /usr/share/ruby/2.0.0/mkmf.rb:336:in `postpone'  from
> /usr/share/ruby/2.0.0/mkmf.rb:894:in `checking_for'  from
> /usr/share/ruby/2.0.0/mkmf.rb:1043:in `have_header'  from
> extconf.rb:16:in `<main>'
> 
> extconf failed, exit code 1

I tried to install ffi ("gem install ffi" and "gem install ffi --pre"),I got the same message

here is the log (.gem/ruby/extensions/x86_64-cygwin/ffi-1.9.5/gem_make.out)

package configuration for libffi is not found 
"gcc -o conftest.exe -I/usr/include/ruby-2.0.0 -I/usr/include/ruby-2.0.0/ruby/backward -I/usr/include/ruby-2.0.0 -I. -ggdb -O2 -pipe -Wimplicit-function-declaration conftest.c -L. -L/usr/lib -L. -fstack-protector -lruby200 -lpthread -lrt -ldl -lcrypt " 
checked program was: 
/* begin */ 
1: #include "ruby.h" 
2: 
3: int main(int argc, char **argv) 
4: { 
5: return 0; 
6: } 
/* end */

I'm really frustrated!!'

system Windows 7 64bit Cygwin

Answer 1

make sure that xcode is installed.

xcode-select --install

if it is already installed, make sure that you have accepted the TOS.

sudo xcodebuild -license

scroll down to the bottom and type agree.

it should work with above steps.

if you see following issue after doing above 2 steps

ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/compass

try following.

sudo su
sudo gem install -n /usr/local/bin compass

Answer 2

Yep, for me it's just the gcc environment,so you can try

sudo apt-get install gcc

That worked for me in ubuntu :)

Answer 3

try this out:

download and install ruby dev kit as per your ruby version

http://rubyinstaller.org/downloads/

in case of any issue follow this wiki on github.

https://github.com/oneclick/rubyinstaller/wiki/Development-Kit

Answer 4

On OSX this worked:

if gem install compass fails, try

gem install ffi in case that also fails, the error seems to be, that the ffi build looks in /usr/bin for gcc-4.2

if you have gcc installed, just create a symlink within /usr/bin by typing

sudo ln -s gcc gcc-4.2

otherwise you may need to first install gcc (google that)