bug#19482: Changing to big font cause display problem

[martin rudalics]

>> IIUC this means that Emacs tries in `set-frame-font' to make your frame
>> larger than your display which sounds like a bad idea.
>>
>> Try first to make the frame smaller before you call `set-frame-font'
>> such that the resizing step in that function stays within the limits of
>> the display and see whether the problem persists.
>>
>> Next try instead of (3) to maximize the frame and then restore its
>> normal size, that is, the one after `set-frame-font', and see whether
>> the problem persists (here I would simply type M-F10 twice).
>>
>> Finally, set the variable `frame-inhibit-implied-resize' to t, call
>> `set-frame-font' and see whether the problem persists.
>>
>> martin
>
> The two tries both make the problem disappear. Setting the variable 
> `frame-inhibit-implied-resize' to t has no effect.
> It seems that the variable is not defined in version 24.4.90.

`frame-inhibit-implied-resize' is defined only in Emacs 25 so you would
have to test this with the "nightlies" I mentioned earlier.

Two more questions:

- After doing your `set-frame-font' how much of the frame do you see?
  Do you see the upper left corner, the frame's title?  Do you notice
  that the frame is larger than your display?  For example, if you can
  see the frame's title, you should not see the frame's echo area.

- When you "maximize the frame and then restore its normal size" does
  the frame have the size it had after the `set-frame-font' or did it
  change in some way?  What does (window--dump-frame) give here?

martin