On 08/09/17 13:16, John Conover wrote:
> In GNUmakefile or makefile mode, PageDown and PageUp cause "Symbol's
> function definition is void: screen-width".
> 
> Is there a fix?

My impression is that either you have found a bug or another package is
interfering. Check if you have the same problem launching emacs with
“emacs -Q” (this disables all your extensions. If that is the case,
report is as a bug.

You may be interested in knowing that C-v and M-v can be used instead of
Page-down and Page-up.

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