[ovs-git] [openvswitch/ovs] 4c16ee: acinclude: fix issue when configuring with --with-...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/openvswitch/ovs
  Commit: 4c16ee484e2f3c7888ec33e8260f868605568027
      https://github.com/openvswitch/ovs/commit/4c16ee484e2f3c7888ec33e8260f868605568027
  Author: Mauricio Vasquez B <mauricio.vasquezbernal at studenti.polito.it>
  Date:   2016-06-01 (Wed, 01 Jun 2016)

  Changed paths:
    M acinclude.m4

  Log Message:
  -----------
  acinclude: fix issue when configuring with --with-dpdk

when an empty path is given to the --with-dpdk option
(--with-dpdk="" or --width-dpdk=$NON_SET_ENV_VARIABLE) the configure
script does not show any error and configures OvS without DPDK support,
this can create some confusion.

This patch modifies that behavior showing an explicity error in that case.

Signed-off-by: Mauricio Vasquez B <mauricio.vasquezbernal at studenti.polito.it>
Signed-off-by: Ben Pfaff <blp at ovn.org>