When I start Emacs with
emacs -Q --eval '(set-face-attribute (quote default) nil :height 180), the font changes for a split-second, but then returns to its default. Same thing if I put the code in my init file.
If I deliberately cause an error with
emacs -Q --eval '(progn (set-face-attribute (quote default) nil :height 180) (bing)), the change sticks. But this doesn't work if I put the code in my init file—I guess that whatever mechanism Emacs uses to recover from init-file errors doesn't prevent the font-size-revert code from running.
How do I get Emacs to accept my default font size?
I'm running Emacs 25.1.2 (from kelleyk's PPA) on Ubuntu 16.10.