When trying to get nokogiri installed with 1.9.3-p362 in a RVM environment on Debian 6 I ran into the following issue:
----- libxml2 is missing. please visit http://nokogiri.org/tutorials/installing_nokogiri.html for help with installing dependencies. ----- *** 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.
And in mkmf.log I saw:
find_library: checking for xmlParseDoc() in -lxml2... -------------------- no
which was pretty confusing, as libxml2 and libxml2-dev along with the other libraries was installed.
As it turned out, what fixed this was:
$ rvm cleanup all $ rvm pkg uninstall libxml2 $ rvm reinstall all --force
Apparently, RVM maintained its very own (outdated?) version of libxml2 and used it for compiling gems. Cleanup, uninstalling the pkg and reinstalling the ruby seems to be a way out of this trouble.