[BUG] git crashes on simple rev-parse incantation

$ git --version git version 2.34.1 $ uname -a Linux zed 5.15.0-48-generic #54-Ubuntu SMP Fri Aug 26 13:26:29 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

I get:

$ git rev-parse --parseopt -- <<<$'x\n--\n=, x\n' fatal: Out of memory, malloc failed (tried to allocate 18446744073709551615 bytes)

---- Here's a less cryptic that fails the same way:

OPTS_SPEC="\ some-command [<options>] <args>...

some-command does foo and bar! -- h,help show the help =,equal nooooooooooooo! "

echo "$OPTS_SPEC" |
  git rev-parse --parseopt --

---- '=' as a short form in the opts spec seems to be the culprit.

I was trying to see what short options could be parsed like '-9', '-_', '-+', etc.

In addition to '=', '!' and '*' also cause crashes. I tested all the other ascii punctuation and didn't see crashes.