--- configure.ac
+++ configure.ac
@@ -284,6 +284,7 @@
 	AC_MSG_RESULT(no)
 
 	AC_MSG_CHECKING(for b64_ntop with -lresolv)
+	b64_ntop_save_LIBS="$LIBS"
 	LIBS="$LIBS -lresolv"
 	AC_TRY_LINK(
 		[
@@ -296,6 +297,7 @@
 		found_b64_ntop=no
 	)
 	if test "x$found_b64_ntop" = xno; then
+		LIBS="$b64_ntop_save_LIBS"
 		AC_MSG_RESULT(no)
 	fi
 fi
--- configure
+++ configure
@@ -6132,6 +6132,7 @@
 
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for b64_ntop with -lresolv" >&5
 $as_echo_n "checking for b64_ntop with -lresolv... " >&6; }
+	b64_ntop_save_LIBS="$LIBS"
 	LIBS="$LIBS -lresolv"
 	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
@@ -6157,6 +6158,7 @@
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
 	if test "x$found_b64_ntop" = xno; then
+		LIBS="$b64_ntop_save_LIBS"
 		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
 	fi