(no commit message)

diff --git a/MagickWand/operation.c b/MagickWand/operation.c
index 6f4160df363f51a9e995eb24554cc8ec015f9be0..34837841cca09abd9163842946f311227d2f06a3 100644 (file)
--- a/MagickWand/operation.c
+++ b/MagickWand/operation.c
@@ -4155,6 +4155,7 @@ WandPrivate MagickBooleanType CLIListOperatorImages(MagickCLI *cli_wand,
               /*
                 Support old style syntax, filter="-option arg1".
               */
+              assert(arg1 != (unsigned char *) NULL);
               length=strlen(arg1);
               token=(char *) NULL;
               if (~length >= (MaxTextExtent-1))