Failure to build on powerpc64le

[daxtens]

Hi,

When I try to gem install memcache on powerpc64le, I get the following failure:

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

    /usr/local/rvm/rubies/ruby-2.2.2/bin/ruby -r ./siteconf20160229-63-6g2jvf.rb extconf.rb
Building libmemcached.
tar xzf libmemcached-1.0.16.tar.gz 2>&1
./configure --prefix=/usr/local/rvm/gems/ruby-2.2.2/gems/memcache-1.5.1/ext --without-memcached --disable-dependency-tracking  2>&1
checking build system type... build-aux/config.guess: unable to guess system type

This script, last modified 2012-06-10, has failed to recognize
the operating system you are using. It is advised that you
download the most up to date version of the config scripts from

  http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD
and
  http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub;hb=HEAD

If the version you run (build-aux/config.guess) is already up to date, please
send the following data and any information you think might be
pertinent to <config-patches@gnu.org> in order to provide the needed
information to handle your system.

config.guess timestamp = 2012-06-10

uname -m = ppc64le
uname -r = 4.2.0-30-generic
uname -s = Linux
uname -v = #35-Ubuntu SMP Fri Feb 19 13:50:54 UTC 2016

/usr/bin/uname -p = 
/bin/uname -X     = 

hostinfo               = 
/bin/universe          = 
/usr/bin/arch -k       = 
/bin/arch              = 
/usr/bin/oslevel       = 
/usr/convex/getsysinfo = 

UNAME_MACHINE = ppc64le
UNAME_RELEASE = 4.2.0-30-generic
UNAME_SYSTEM  = Linux
UNAME_VERSION = #35-Ubuntu SMP Fri Feb 19 13:50:54 UTC 2016
configure: error: cannot guess build type; you must specify one

I'm pretty sure this is due to the version of libmemcached that you bundle: I'm just checking to see if installing a system version of libmemcached-dev is sufficient to work around this.

[daxtens]

So I've done some further checks: because you're gem doesn't seem to let the system version of libmemcached override the bundled version, you can fix this by bumping the version of libmemcached you bundle to 1.0.18.

I can send a pull request to this effect if you like.