Re: DOC for Mac OS shown for Emacs compiled for X.

[Richard Stallman]

    1.  make-docfile should not read the .c file if the .o one does not exist.
    2.  Emacs is supposed to find the correct entry in DOC.
    3.  macfns.o should not be in SOME_MACHINE_OBJECTS when building for X.
    4.  Symbols that occur in several files (x, mac, w32) should have the same 
doc
         string.

If we make sure macfns.c has only functions and variables that appear
also in xfns.c, then we can always omit macfns.o from
SOME_MACHINE_OBJECTS.  The doc strings that are really used would come
from xfns.c, regardless of the platform.  We could replace the doc
strings in macfns.c with "This is a dummy--see xfns.c", so people
won't waste time editing them.

#1 is also a possible solution.  It is more general, since it could
handle other problems too.  Maybe we should choose that.