switch UI: Only build ovs-switchui if PCRE 7.2 or later is available.

The PCRE_INFO_OKPARTIAL feature used by ovs-switchui was only introduced
in PCRE 7.2, so we need to check for that version or later, instead of
just for PCRE.

Thanks to Ian Campbell <Ian.Campbell@citrix.com> for reporting the problem.

diff --git a/m4/openvswitch.m4 b/m4/openvswitch.m4
index 3fe053b..d65baba 100644 (file)
--- a/m4/openvswitch.m4
+++ b/m4/openvswitch.m4
@@ -228,7 +228,7 @@ dnl Checks for libpcre.
 AC_DEFUN([OVS_CHECK_PCRE],
   [dnl Make sure that pkg-config is installed.
    m4_pattern_forbid([PKG_CHECK_MODULES])
-   PKG_CHECK_MODULES([PCRE], [libpcre], [HAVE_PCRE=yes], [HAVE_PCRE=no])
+   PKG_CHECK_MODULES([PCRE], [libpcre >= 7.2], [HAVE_PCRE=yes], [HAVE_PCRE=no])
    AM_CONDITIONAL([HAVE_PCRE], [test "$HAVE_PCRE" = yes])
    if test "$HAVE_PCRE" = yes; then
       AC_DEFINE([HAVE_PCRE], [1], [Define to 1 if libpcre is installed.])