Additional odd behavior after my upgrade to the latest CYGWIN64 version

Cygwin handles (filename) case insensitivity in a very weird way at the Windows command prompt: -- c:\Users\Michael>set CYGWIN= c:\Users\Michael>printf "%q " 'a' 'A' "a" "A" a A a A a A a A REM OK, so far so good, but, now: c:\Users\Michael>set CYGWIN=glob:ignorecase

The grep 3.11 application when used in perl-regexp mode appears to now be broken

I just updated my Cygwin64 installation, which includes the grep utility and its behavior has changed. It no longer works like it used to for Perl reg-ex matching, as demonstrated below: Simple test cases: == $ ls -l a -rwxr-xr-x 1 Michael None 6 Mar 16 12:15 a $ hexdump -C a