Rails 3.2.3 MySQL 5.5.1 Mysql2 gem install fails with ld incompatibilities

问题

I have a clean build system as follows

Ubuntu 11.04

Rvm 1.13.5

Ruby 1.9.3p194

Rails 3.2.3

Gem 1.8.24

MySql 5.5.24-1 (installed in /usr/local)

I am trying to install the mysql2 gem (0.3.11) and getting the following problem:

 pal@smurf01:~$ sudo gem install mysql2
   [sudo] password for pal: 
   Building native extensions.  This could take a while...
   ERROR:  Error installing mysql2:
        ERROR: Failed to build gem native extension.

        /usr/local/rvm/rubies/ruby-1.9.3-p194/bin/ruby extconf.rb
   checking for rb_thread_blocking_region()... yes
   checking for rb_wait_for_single_fd()... yes
   checking for mysql.h... yes
   checking for errmsg.h... yes
   checking for mysqld_error.h... yes
   creating Makefile

   make
   compiling client.c
   client.c: In function 'rb_raise_mysql2_error':
   client.c:98:3: warning: ISO C90 forbids mixed declarations and code
   client.c: In function 'rb_mysql_client_socket':
   client.c:590:3: warning: ISO C90 forbids mixed declarations and code
   compiling mysql2_ext.c
   compiling result.c
   linking shared-object mysql2/mysql2.so
   /usr/bin/ld: skipping incompatible /usr/local/mysql/lib/libmysqlclient_r.so when searching for -lmysqlclient_r
   /usr/bin/ld: skipping incompatible /usr/local/mysql/lib/libmysqlclient_r.a when searching for -lmysqlclient_r
   /usr/bin/ld: cannot find -lmysqlclient_r
   collect2: ld returned 1 exit status
   make: *** [mysql2.so] Error 1


   Gem files will remain installed in /usr/local/rvm/gems/ruby-1.9.3-p194/gems/mysql2-0.3.11 for inspection.
   Results logged to /usr/local/rvm/gems/ruby-1.9.3-p194/gems/mysql2-0.3.11/ext/mysql2/gem_make.out
 pal@smurf01:~$

First question: Has anyone got Rails mysql2 running with MySql 5.5.1 on Ubuntu? I have it running on another system with 5.1. The gem description is vague on supported MySql versions.

Second question: Has anyone encountered this problem? I± have battled various library issues with the mysql2 gem over the passed year or so but this seems to be different.

Any assistance is gratefully recieved.

BTW: Reverting back to MySql 5.1 is a valid solution!

Regards

Peter

回答1:

Or just apt-get install libmysqlclient-dev and then gem install mysql2

回答2:

So the problem appears to have been a missing library and some links. Doing the following solved the issue.

Get the new and install the libmysqlclient-dev deb package kindly provided by Nathan Rennie Waldock

 wget http://ppa.launchpad.net/nathan-renniewaldock/ppa/ubuntu/pool/main/m/mysql-5.5/libmysqlclient-dev_5.5.24-1~ppa1~natty_amd64.deb./;l
 dpkg -i libmysqlclient-dev_5.5.24-1~ppa1~natty_amd64.deb

Then create some links that mysql2 needs as it can't seem to follow the mysql path

cd /usr/lib/
ln -s /usr/local/mysql-5.5.24-linux2.6-x86_64/lib/libmysqlclient_r.a .
ln -s /usr/local/mysql-5.5.24-linux2.6-x86_64/lib/libmysqlclient_r.so .
ln -s /usr/local/mysql-5.5.24-linux2.6-x86_64/lib/libmysqlclient_r.so.18 .
ln -s /usr/local/mysql-5.5.24-linux2.6-x86_64/lib/libmysqlclient_r.so.18.0.0 .

Now happily install the mysql2 gem

sudo gem install mysql2
  Fetching: mysql2-0.3.11.gem (100%)
  Building native extensions.  This could take a while...
  Successfully installed mysql2-0.3.11
  1 gem installed
  Installing ri documentation for mysq2l-0.3.11...
  Installing RDoc documentation for mysql2-0.3.11...

回答3:

Had the same issue in Ubuntu 12.04 also using the ppa mentioned in the accepted answer. But also there was no libmysqlclient file on my system with _r in the name. Googling around I found out that package builders have started to drop the _r suffix from the files, so that might have happened between 11.10 and 12.04.

Also the paths were a bit different to the once mentioned so these are the symlinks that I had to create:

ln -s /usr/lib/x86_64-linux-gnu/libmysqlclient.a ./libmysqlclient_r.a
ln -s /usr/lib/x86_64-linux-gnu/libmysqlclient.so ./libmysqlclient_r.so
ln -s /usr/lib/x86_64-linux-gnu/libmysqlclient.so.18 ./libmysqlclient_r.so.18
ln -s /usr/lib/x86_64-linux-gnu/libmysqlclient.so.18.0.0 ./libmysqlclient_r.so.18.0.0

回答4:

I had this problem as well...

I did dpkg -r mysql-devel as when I was trying to do apt-get install libmysqlclient-dev I got an error saying:

Unpacking libmysqlclient-dev (from .../libmysqlclient-dev_5.5.24-0ubuntu0.12.04.1_i386.deb) ... dpkg: error processing /var/cache/apt/archives/libmysqlclient-dev_5.5.24-0ubuntu0.12.04.1_i386.deb (--unpack): trying to overwrite '/usr/bin/mysql_config', which is also in package mysql-devel 5.5.28-2

After doing this, gem install mysql2 worked! yay :)

来源：https://stackoverflow.com/questions/10634949/rails-3-2-3-mysql-5-5-1-mysql2-gem-install-fails-with-ld-incompatibilities