Comment 2 for bug 1940996

Minimized testcases (same regex):

$ echo 8 | grep -E -e "$regex"
8 # >>> okay
$ echo 87 | grep -E -e "$regex"
Segmentation fault

$ echo 88 | grep -E -e "$regex"
88 # >>> okay
$ echo 887 | grep -E -e "$regex"
Segmentation fault

Also, everything I tried to feed that is of length 9 or higher and should not
match, gives either a false positive or a segfault:

$ echo 987654321 | grep -E -e "$regex"
887654321
$ echo 484635532 | grep -E -e "$regex"
484635532
$ echo 0123454321 | grep -E -e "$regex"
Segmentation fault
$ echo 0000123454321 | grep -E -e "$regex"
Segmentation fault