diff --git a/tools/tiff2ps.c b/tools/tiff2ps.c
index 82a5d84..3563f30 100644
--- a/tools/tiff2ps.c
+++ b/tools/tiff2ps.c
@@ -2964,7 +2964,9 @@ tsize_t Ascii85EncodeBlock( uint8 * ascii85_p, unsigned f_eod, const uint8 * raw
     
             if ( val32 == 0 )                   /* Special case */
             {
-                ascii85_p[ascii85_l] = 'z';
+                if(ascii85_p != NULL) {
+                    ascii85_p[ascii85_l] = 'z';
+                }
                 rc = 1;
             }
     
diff --git a/tools/tiffcrop.c b/tools/tiffcrop.c
index 722b132..7664556 100644
--- a/tools/tiffcrop.c
+++ b/tools/tiffcrop.c
@@ -1745,7 +1745,7 @@ void  process_command_opts (int argc, char *argv[], char *mp, char *mode, uint32
       case 'C': *mp++ = 'c'; *mp = '\0';
 		break;
       /* options for Debugging / data dump */
-      case 'D': for (i = 0, opt_ptr = strtok (optarg, ",");
+      case 
                     (opt_ptr != NULL);
                     (opt_ptr = strtok (NULL, ",")), i++)
                     {