Debian: https://sources.debian.net/src/dvd%2Brw-tools/7.1-11.1/debian/patches/03-growisofs-dvd-dl.patch/

Author: Joe Shaw <joeshaw@suse.de>
Description: Don't abort when a DVD-DL disk is underful (Closes: #340698).

--- a/growisofs_mmc.cpp
+++ b/growisofs_mmc.cpp
@@ -1640,9 +1640,7 @@
     blocks += 15, blocks &= ~15;
 
     if (blocks <= split)
-	fprintf (stderr,":-( more than 50%% of space will be *wasted*!\n"
-			"    use single layer media for this recording\n"),
-	exit (FATAL_START(EMEDIUMTYPE));
+	fprintf (stderr,":-? more than 50%% of space will be *wasted*!\n");
 
     blocks /= 16;
     blocks += 1;