autogen.sh: Allow to configure Autoconf warnings.

Same as in tcpslice and libpcap.

Author: infrastation

.cirrus.yml

@@ -1,6 +1,7 @@
 env:
   CIRRUS_CLONE_DEPTH: 3 # The internal git client reads CIRRUS_CLONE_DEPTH.
   LIBPCAP_GIT: https://github.com/the-tcpdump-group/libpcap.git
+  AUTOCONF_WARNINGS: no-obsolete
 
 freebsd_task:
   name: freebsd-amd64

CHANGES

@@ -65,6 +65,7 @@ DayOfTheWeek, Month DD, YYYY / The Tcpdump Group
       Makefile.in: Do not install a version-suffixed tcpdump binary if the
         .devel file does not exists.
       tests: On HP-UX use "diff -c" by default.
+      autogen.sh: Allow to configure Autoconf warnings.
     Documentation:
       man: Clarify the "any" pseudo-interface further.
 

Makefile.in

@@ -481,7 +481,7 @@ releasetar:
 	     tar xf -) && \
 	    echo "No $$TAG tag. Archive build from HEAD."; \
 	fi && \
-	(cd "$$TAG" && "$${AUTORECONF:-autoreconf}" && rm -rf autom4te.cache) && \
+	(cd "$$TAG" && ./autogen.sh && rm -rf autom4te.cache) && \
 	tar cf "$$DIR/$$TAG".tar "$$TAG" && \
 	rm -f "$$DIR/$$TAG".tar.gz && \
 	gzip --best "$$DIR/$$TAG".tar && \

autogen.sh

@@ -22,4 +22,10 @@ if [ "$maj" = "" ] || [ "$min" = "" ] || \
 fi
 
 echo "$AUTORECONF identification: $AUTORECONFVERSION"
-"$AUTORECONF" -f
+
+# configure.ac is an Autoconf 2.69 file, but it works as expected even with
+# Autoconf 2.72.  However, in Autoconf versions 2.70 and later obsolete
+# construct warnings are enabled by default, which adds varying (depending on
+# the branch) amount of noise to the build matrix output, so provide a means
+# to silence that.
+env ${AUTOCONF_WARNINGS:+WARNINGS="$AUTOCONF_WARNINGS"} "$AUTORECONF" -f