Dear Maintainer,

editing around in my ~/.Xdefaults, I ended up accidentally setting a zero font
size, like:

  URxvt*font:     xft:mono:medium:size=0

(It should have said 10 but a stray typo saved the size as 0).

With this config merged to xrdb, launching a urxvt opens a window, then goes on
to halt the entire xorg with CPU load for a minute or so, and ends up crashing
xorg completely to bring back the login screen.

Using i3wm and xdm. I've attached an Xorg log.

Needless to say that urxvt should worst-case refuse to start instead of
bringing the entire wm down...

TBH I haven't investigated whether this should be prevented by an xorg API or
whether it is urxvt's responsibility to prevent a zero font size, I hope you
have a better bearing on where this belongs than I do. Thanks!

~N