pkg/56913: privoxy fails to start on macOS

[simmonds%polymorphism.ca@localhost]

>Number:         56913
>Category:       pkg
>Synopsis:       privoxy fails to start on macOS
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jul 06 18:25:00 +0000 2022
>Originator:     Colin Simmonds
>Release:        pkgsrc from git trunk (b883e4562afaf56f74fcea3691439ca17aaafb8e)
>Organization:
>Environment:
Darwin Meiling.hitronhub.home 21.5.0 Darwin Kernel Version 21.5.0: Tue Apr 26 21:08:37 PDT 2022; root:xnu-8020.121.3~4/RELEASE_ARM64_T6000 arm64 arm64 MacBookPro18,2 Darwin

>Description:
privoxy fails to start when run on my macOS machine.

With the log level turned up in the config file, I see the following in the log file:
2022-07-04 14:12:30.705 00102ee0 Error: error compiling /.*\.(gif|jpe?g|png|bmp|ico)($|\?) from /.*\.(gif|jpe?g|png|bmp|ico)($|\?): invalid argument to regex routine
2022-07-04 14:12:30.705 00102ee0 Fatal error: can't load actions file '/opt/pkg/etc/privoxy/default.action': line 624: cannot create URL or TAG pattern from: /.*\.(gif|jpe?g|png|bmp|ico)($|\?)

coming from one of the default patterns in the included default.action file
>How-To-Repeat:
Add "privoxy=YES" to /etc/rc.conf

/etc/rc.d/privoxy start

and privoxy exits immediately with exit code 1.
>Fix:
I found that the problem goes away if I build it without pthreads support. In the Makefile, I commented out the lines referring to pthreads:

#PTHREAD_AUTO_VARS=	yes
#PTHREAD_OPTS+=		require

#.include "../../mk/pthread.buildlink3.mk"