[bug-diffutils] bug#27241: diff command modified my file

[Hong Jehn]

When I use command "diff -qr abc/ usb/abc/" to compare 2 directory,  it changes 
the "centos_7_x86_64_Minimal.iso" sometime but the file size didn't change even 
when I just ran the same command and it says they are the same. Other file are 
fine, it changes only this iso file.

Also, I wrote a similler program like diff before it came out the same problem. 
I guess it's a glibc bug? I kept the broken file in case you need it.

This problem comes out like once a week, I kept the sha256-code but this 
problem seems serious.