diff --git a/djpeg.c b/djpeg.c
index 9cfaad06..72d906ed 100644
--- a/djpeg.c
+++ b/djpeg.c
@@ -573,7 +573,7 @@ main (int argc, char **argv)
         else
           fprintf(stderr, "%s: can't read from stdin\n", progname);
       }
-      insize += nbytes;
+      insize += (unsigned long)nbytes;
     } while (nbytes == INPUT_BUF_SIZE);
     fprintf(stderr, "Compressed size:  %lu bytes\n", insize);
     jpeg_mem_src(&cinfo, inbuffer, insize);
diff --git a/jdatadst.c b/jdatadst.c
index ff87ecd7..b3fdd3ed 100644
--- a/jdatadst.c
+++ b/jdatadst.c
@@ -191,7 +191,7 @@ term_mem_destination (j_compress_ptr cinfo)
   my_mem_dest_ptr dest = (my_mem_dest_ptr) cinfo->dest;
 
   *dest->outbuffer = dest->buffer;
-  *dest->outsize = dest->bufsize - dest->pub.free_in_buffer;
+  *dest->outsize = (unsigned long)(dest->bufsize - dest->pub.free_in_buffer);
 }
 #endif