How to set up a bridge with "bridge_ports none" on Debian Stretch in /etc/network/interfaces?

Question

When I have configured br0 in /etc/network/interfaces with

iface br0 inet static
    address 10.0.10.1
    gateway 10.0.10.1
    netmask 255.255.255.0
    broadcast 10.0.10.254
    bridge_ports none

and when I try to raise br0

$ ifup br0

Waiting for br0 to get ready (MAXWAIT is 32 seconds).
RTNETLINK answers: Invalid argument
ifup: failed to bring up br0

/var/log/syslog says:

Could not generate persistent MAC address for br0: No such file or directory

Then in order to fix that, I found someone on the internet mentioning systemd's MACAdressPolicy in a more or less similar issue :

udevd: "Could not generate persistent MAC address for $name: No such file or directory"

I placed following content in /etc/systemd/network/99-default.link:

[Link]
NamePolicy=kernel database onboard slot path
MACAddressPolicy=none

But - still, when I

$ ifup br0

Waiting for br0 to get ready (MAXWAIT is 32 seconds).
RTNETLINK answers: Invalid argument
ifup: failed to bring up br0

but /var/log/syslog contains no information about that event

Do you have a clue how a working configuration should look like?

Answer 1

Setting the default gateway to your own IP address doesn't make much sense thus isn't accepted:

$ sudo ifup -v br0

ifup: configuring interface br0=br0 (inet)
/bin/run-parts --exit-on-error --verbose /etc/network/if-pre-up.d
run-parts: executing /etc/network/if-pre-up.d/bridge

Waiting for br0 to get ready (MAXWAIT is 32 seconds).
run-parts: executing /etc/network/if-pre-up.d/vde2
run-parts: executing /etc/network/if-pre-up.d/wpasupplicant
/bin/ip addr add 10.0.10.1/255.255.255.0 broadcast 10.0.10.254    dev br0 label br0
/bin/ip link set dev br0   up
 /bin/ip route add default via 10.0.10.1  dev br0 onlink 
RTNETLINK answers: Invalid argument
ifup: failed to bring up br0

Your broadcast setting is suspicious as well, the customary value would be 10.0.10.255, which you wouldn't even need to specify. Just use modern syntax:

iface br0 inet static
    address      10.0.10.1/24
    bridge_ports none