+--- libredwg-0.12.4/configure.ac.orig 2021-04-11 15:41:32.582128469 +0200
++++ libredwg-0.12.4/configure.ac 2021-04-11 16:42:30.718977307 +0200
+@@ -407,13 +407,9 @@
+ if test -n "$GPERF"
+ then
+ AC_MSG_CHECKING([GPERF version])
+- [GPERF_VERSION=`"$GPERF" --version | head -n1 2>&1 | sed 's,GNU gperf ,,'`]
+- case $GPERF_VERSION in
+- 1.*) GPERF_VERSION=$((100+${GPERF_VERSION:2:1})) ;;
+- 2.*) GPERF_VERSION=$((200+${GPERF_VERSION:2:1})) ;;
+- 3.*) GPERF_VERSION=$((300+${GPERF_VERSION:2:1})) ;;
+- 4.*) GPERF_VERSION=$((400+${GPERF_VERSION:2:1})) ;;
+- esac
++ [GPERF_MAJOR=`"$GPERF" --version | head -n1 2>&1 | sed 's,GNU gperf ,,' | cut -d. -f1`]
++ [GPERF_MINOR=`"$GPERF" --version | head -n1 2>&1 | sed 's,GNU gperf ,,' | cut -d. -f2`]
++ GPERF_VERSION=$((GPERF_MAJOR * 100 + GPERF_MINOR))
+ AC_MSG_RESULT([$GPERF_VERSION])
+ AC_DEFINE_UNQUOTED([GPERF_VERSION],[$GPERF_VERSION],
+ [versions earlier than 301 will have no size_t])