SocksPort with IPv6 address is silently ignored

There appears to be a regression in 0.4.5.1-alpha that leads to explicit IPv6 addresses in SocksPort being ignored.

When using this /etc/torrc:

SocksPort 127.0.0.1:9050
SocksPort [::1]:9050

I see both ports being bound in 0.4.4.5:

user@disp9699:~$ sudo netstat -npel --inet --inet6 |grep tor
tcp        0      0 127.0.0.1:9050          0.0.0.0:*               LISTEN      0          25811      1073/tor            
tcp6       0      0 ::1:9050                :::*                    LISTEN      0          25812      1073/tor    

However, in 0.4.5.1-alpha, only IPv4 is bound:

user@disp9699:~$ sudo netstat -npel --inet --inet6 |grep tor
tcp        0      0 127.0.0.1:9050          0.0.0.0:*               LISTEN      0          33626      4217/tor    

I had a quick look at the debug logs and I could not find any indication that Tor even tries to bind to the IPv6 port.

Setup details:

• OS: Debian 10 (on Qubes OS)
• Repo: deb.torproject.org