--- configure.orig	2019-07-12 20:22:02 UTC
+++ configure
@@ -154,7 +154,7 @@ do
       CXXFLAGS="`expr \"$1\" : 'CXXFLAGS=\(.*\)'`"
       ;;
 
-    *) die "invalid option '$1' (try '-h')";;
+    *) ;;
 
   esac
   shift
@@ -396,7 +396,7 @@ sed \
 -e "2c\\
 # This 'makefile' is generated from '../makefile.in'." \
 -e "s,@CXX@,$CXX," \
--e "s,@CXXFLAGS@,$CXXFLAGS," \
+-e "s|@CXXFLAGS@|$CXXFLAGS|" \
 -e "s,@MAKEFLAGS@,$MAKEFLAGS," \
 ../makefile.in > makefile