Thanks for the bug report. I installed the attached, a bit simpler than 
the patch you suggested; can you please give it a try?

Also, is there a related bug near dfltcc.c line 375? That is, when 
(inptr == insize && fill_inbuf (1) == EOF && param->cf), won't insize 
then be zero, so that gzip will go into an infinite loop attempting to 
read past EOF?