Dear Grep team,

My installation of grep thinks [a-Z] is a valid range, while [A-z] is not.

OS:

ArcoLinux

Kernel Version:
5.11.1-zen1-1-zen

Grep Version:

grep (GNU grep) 3.6

Shell Version:
GNU bash, version 5.1.4(1)-release (x86_64-pc-linux-gnu)

Locale:
en_US.utf8

Steps to reproduce:

$ echo "test" | grep -E "[a-Z]"
test

$ echo "test" | grep -E "[A-z]"

grep: Invalid range end

Please, let me know if I can produce some debug log for you.

Best,

George