perl 5.22 causes warnings when zsh calls it

[John <da_audiophile@xxxxxxxxx>]

Using Arch Linux + grml-zsh-config and zsh version 5.0.8 with the latest release of perl (5.22.0) causes warning messages when zsh calls perl.  Specifically, switching themes that have a token via `prompt adam1 yellow` can trigger it due to zsh invoking a perl line that the new version of perl doesn't like.  This was not the case under the older version of perl.

Under perl 5.20.2-1:
3:02% prompt adam1 yellow
facade@playtime ~ %
Under perl 5.22.0-1:

3:03% prompt adam1 yellow
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/%(K{ <-- HERE .*?}|k)/ at -e line 1.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/%(K{ <-- HERE .*?}|k)/ at -e line 1.

facade@playtime ~ %

If I `set -x` in an attempt to debug, I found this line which I believe zsh is calling:


...
+prompt_adam1_setup:8:> base_prompt_no_color=+prompt_adam1_setup:8:cmdsubst pipe> perl -pe 's/%(K{.*?}|k)//g'
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/%(K{ <-- HERE .*?}|k)/ at -e line 1.

Note - I am not subscribed to the ML so please remember to cc me on all subsequent correspondence.