Require pkg-config 0.26 or later in autogen.sh only.

* autogen.sh (pkg_config_min): Make this at least 0.26.
* configure.ac (PKG_PROG_PKG_CONFIG): Revert back to 0.9.0.

Fixes: debbugs:17438

ChangeLog

@@ -3,7 +3,7 @@
 	Require pkg-config 0.26 or later (Bug#17438).
 	Earlier versions are buggy, as pkg-config --libs can output
 	nothing, which causes xrandr link failures.
-	* configure.ac (PKG_PROG_PKG_CONFIG): Bump from 0.9.0 to 0.26.
+	* autogen.sh (pkg_config_min): Make this at least 0.26.
 
 2014-05-07  Glenn Morris  <rgm@gnu.org>
 

autogen.sh

@@ -42,6 +42,11 @@ autoconf_min=`sed -n 's/^ *AC_PREREQ(\([0-9\.]*\)).*/\1/p' configure.ac`
 automake_min=`sed -n 's/^ *AM_INIT_AUTOMAKE(\([0-9\.]*\)).*/\1/p' configure.ac`
 
 pkg_config_min=`sed -n 's/^ *PKG_PROG_PKG_CONFIG(\([0-9\.]*\)).*/\1/p' configure.ac`
+# Building from the repository needs pkg-config 0.26 or later; see Bug#17438.
+case $pkg_config_min in
+  0.[0-9] | 0.[0-9].* | 0.1[0-9] | 0.1[0-9].* | 0.2[0-5] | 0.2[0-5].* )
+    pkg_config_min=0.26
+esac
 
 ## $1 = program, eg "autoconf".
 ## Echo the version string, eg "2.59".

configure.ac

@@ -1349,7 +1349,7 @@ searched by pkg-config])
 pre_PKG_CONFIG_CFLAGS=$CFLAGS
 pre_PKG_CONFIG_LIBS=$LIBS
 
-PKG_PROG_PKG_CONFIG(0.26)
+PKG_PROG_PKG_CONFIG(0.9.0)
 
 dnl EMACS_CHECK_MODULES(GSTUFF, gtk+-2.0 >= 1.3 glib = 1.3.4)
 dnl acts like PKG_CHECK_MODULES(GSTUFF, gtk+-2.0 >= 1.3 glib = 1.3.4,