bug#21413: Top of buffer hidden when toolbar hidden and frame height is large

[martin rudalics]

> Here are the steps to reproduce the problem using the NS build of emacs on OS 
X 10.10.4.
>
> cat >> test-init.el <<EOF
> (tool-bar-mode -1)
> (setq default-frame-alist '((height . 100)))
> EOF
> open -a Emacs.app --args -Q -l ~/test-init.el
>
> This opens a graphical emacs frame showing the *scratch*
> buffer. Neither the cursor is visible, nor is the text normally shown
> in the *scratch* buffer. Scrolling up will not make either of these
> visible. C-x C-f <some file name> RET will display the contents of
> that buffer with some or all of the lines at the start hidden.
>
> The hidden sections of the buffer can be made visible by clicking and
> dragging on any edge of the window and resizing it.

> * Expected behaviour
>
> When I set the frame size to be taller than the screen will allow, I
> expect the frame to occupy as much vertical space as possible without
> the top of the buffer being hidden. This is the behaviour seen when
> tool-bar-mode is on.

This is probably beyond Emacs' control.  I suppose that your window
manager normally tries to assure that the tool bar is visible.  When
there's no tool bar it simply puts the frame somwhere if it's taller
than your screen.

What happpens when you also explicitly put the top left edge at some
visible position like with

(setq default-frame-alist '((top . 5) (left . 5) (height . 100)))

martin