Problem Compiling GEOS-3.4.2 for Saucy Salamander

https://launchpad.net/ubuntu/+ppas?name_filter=geos

No already compiled version here?

Looks like a typo error in a configuration file causing ld to search for "-libruby" instead of "libruby".

What are the five lines preceding the "/usr/bin/ld: cannot find -llibruby-1.9.1.so.1.9.1" error message?

First run these Terminal commands:

sudo apt-get update

sudo apt-get install proj libjson0-dev xsltproc docbook-mathml docbook-xsl

sudo apt-get install postgresql-server-dev-9.1

sudo apt-get install gettext dblatex openjdk-7-jre openjdk-7-jdk icedtea-7-plugin libxml2-dev

sudo apt-get install swig php5-dev phpunit openjpeg-tools libopenjpeg-dev libkml-dev

sudo apt-get install libpoppler-dev expat libexpat1-dev libxerces-c-dev

sudo apt-get install libpoppler19

sudo apt-get install libcurl4-openssl-dev

sudo apt-get install g++ python-dev ruby

sudo apt-get install apache2 python-psycopg2 postgresql build-essential libapache2-mod-python

sudo apt-get install postgresql-8.3-postgis

Source: http://northwestspatial.com/wp/?p=340
Source: https://code.djangoproject.com/wiki/GeoDjangoUbuntuInstall

Next, follow these instructions:

https://github.com/libgeos/libgeos/blob/svn-trunk/INSTALL

I quote:

"
Linux: Make sure that /usr/local/lib is added to /etc/ld.so.conf
       Make sure that you run /sbin/ldconfig afterwards "

I personally recommend adding /usr/local/lib and /usr/lib to /etc/ld.so.conf

Then run this command:

sudo ldconfig

Then run this Terminal command in your home folder:

git clone git://github.com/libgeos/libgeos.git

Then follow these build instructions:

https://github.com/libgeos/libgeos

I quote:

"
BUILDING, TESTING, INSTALLING
=============================

Unix
----

Using Autotools:
  ./autogen.sh # in ${srcdir}, if obtained from SVN
  ${srcdir}/configure # in build dir

Using CMake:
  cmake ${srcdir} # in build dir

Now, all versions:
  make
  make check
  sudo make install
  sudo ldconfig
"

Hope this helps.

I might be completely wrong, but it seems to me that the configure script sets a wrong value for RUBY_LIB_DIR (probably "-llibruby-1.9.1.so.1.9.1" instead of "libruby-1.9.1.so.1.9.1"). So the linker command ends up with a double -l prefix -l-llibruby...

from geos configue script:
RUBY_LIB_DIR=`$RUBY -rrbconfig -e 'puts RbConfig::CONFIG["libdir"] || Config::CONFIG["libdir"]'`

What is the output of
ruby -rrbconfig -e 'puts RbConfig::CONFIG["libdir"]')
ruby -rrbconfig -e 'puts Config::CONFIG["libdir"]')

What are the few lines preceding the "/usr/bin/ld: cannot find -llibruby-1.9.1.so.1.9.1" error message?

Thanks Mark Rijckenberg, that solved my question.

I have used the suggestion from Mark and got around my issue simply by not using RUBY. Thanks for your help guys!

Here's a patch to fix ruby compilation:

diff -uNr geos-3.4.2-orig/swig/ruby/Makefile.am geos-3.4.2/swig/ruby/Makefile.am
--- geos-3.4.2-orig/swig/ruby/Makefile.am 2013-08-25 17:10:32.000000000 +0200
+++ geos-3.4.2/swig/ruby/Makefile.am 2013-12-06 05:24:12.751028564 +0100
@@ -22,7 +22,7 @@
 # Build Ruby module as shared library
 rubyextensiondir_LTLIBRARIES = geos.la
 geos_la_SOURCES = geos_wrap.cxx
-geos_la_LIBADD = $(top_builddir)/capi/libgeos_c.la -l$(RUBY_SO_NAME)
+geos_la_LIBADD = $(top_builddir)/capi/libgeos_c.la $(RUBY_SO_NAME)

 # Only need to grab the capi header files
 geos_la_CPPFLAGS = -I$(top_builddir)/capi
diff -uNr geos-3.4.2-orig/swig/ruby/Makefile.in geos-3.4.2/swig/ruby/Makefile.in
--- geos-3.4.2-orig/swig/ruby/Makefile.in 2013-08-25 17:10:45.000000000 +0200
+++ geos-3.4.2/swig/ruby/Makefile.in 2013-12-06 05:55:10.560028099 +0100
@@ -334,7 +334,7 @@
 # Build Ruby module as shared library
 @ENABLE_RUBY_TRUE@rubyextensiondir_LTLIBRARIES = geos.la
 @ENABLE_RUBY_TRUE@geos_la_SOURCES = geos_wrap.cxx
-@ENABLE_RUBY_TRUE@geos_la_LIBADD = $(top_builddir)/capi/libgeos_c.la -l$(RUBY_SO_NAME)
+@ENABLE_RUBY_TRUE@geos_la_LIBADD = $(top_builddir)/capi/libgeos_c.la $(RUBY_SO_NAME)

 # Only need to grab the capi header files
 @ENABLE_RUBY_TRUE@geos_la_CPPFLAGS = -I$(top_builddir)/capi