ruby - Mac Rmagick won't install with Xcode 4.2

Question

I just got a new macbook pro and trying to setup my dev environment. I downloaded xcode 4.2 from the app store and installed it, after this i installed homebrew and RVM. ImageMagick, readline, ruby 1.9.3-head all installed perfectly until i ran bundle update which tried to install rmagick.

After a long long time investigating i come down to the conclusion that it can't find libgomp.

The output is from gem install rmagick is:

$ gem install rmagick
Building native extensions.  This could take a while...
ERROR:  Error installing rmagick:
        ERROR: Failed to build gem native extension.

        /Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/bin/ruby extconf.rb
checking for Ruby version >= 1.8.5... yes
extconf.rb:128: Use RbConfig instead of obsolete and deprecated Config.
checking for clang... yes
checking for Magick-config... yes
checking for ImageMagick version >= 6.4.9... yes
checking for HDRI disabled version of ImageMagick... yes
checking for stdint.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=/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/bin/ruby
/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/lib/ruby/1.9.1/mkmf.rb:381:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.

Here is my mkmf.log file:

"clang -o conftest -I/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/include/ruby-1.9.1/x86_64-darwin11.2.0 -I/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/include/ruby-1.9.1/ruby/backward -I/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/include/ruby-1.9.1 -I.  -I/usr/local/Cellar/imagemagick/6.7.1-1/include/ImageMagick  -I/usr/local/Cellar/imagemagick/6.7.1-1/include/ImageMagick -fopenmp conftest.c  -L. -L/Users/dhiemstra/.rvm/rubies/ruby-1.9.3-head/lib  -L/usr/local/Cellar/imagemagick/6.7.1-1/lib -L/usr/X11/lib    -L/usr/local/Cellar/imagemagick/6.7.1-1/lib -lMagickCore -llcms -ltiff -lfreetype -ljpeg -L/usr/X11/lib -lfontconfig -lXext -lSM -lICE -lX11 -lXt -lbz2 -lz -lm -lgomp -lpthread -lltdl  -lruby.1.9.1  -lpthread -ldl -lobjc "
ld: library not found for -lgomp
clang: error: linker command failed with exit code 1 (use -v to see invocation)
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main() {return 0;}
/* end */

Now i assumed here that something was wrong with xcode i tried several things:

• Reinstall xcode
• Remove imagemagick and reinstalled it including other libraries like jpg, libpng etc
• Installed older version of imagemagick
• Removed .rvm and reinstalled a fresh copy of ruby

I have no clue what's left for me to try, could anyone help to push me in the good direction?

Answer 1

I tried your solution (full of hope) but It did not work for me unfortunately. Finally I managed to make it work by reinstalling imagemagick without openmp support (this is the library responsible for lgomp)

using Homebrew:

brew install imagemagick --disable-openmp

then rmagick installed without any problems.