gnuplot on 64-bit Windows

[Allin C. <cot...@wf...>]

I have need of a 64-bit Windows build of gnuplot and I've been 
working on cross-compiling from Linux using mingw64. I see 
several places in current CVS where the code generates errors 
and warnings. I'm attaching a patch-set which quells the 
errors and warnings, but unfortunately I'm not able to test on 
win64 at present.

If I'm understanding the code correctly there's one place that 
I haven't patched which may be a problem, namely the 
definition of struct tagLS in win/wgraph.c. The first member 
of this struct is an int ("widtype"). I believe it should be 
redefined for win64 as LONG_PTR, since it is assigned to via
the function GetWindowLong(), which maps to GetWindowLongPtr() 
on win64, and the latter returns a 64-bit pointer.

Some of the changes I've made are actually OK for win32, from 
Windows 2000 onward. But I guess gnuplot aims to support older 
Windows versions than that; I've therefore bracketed all my 
changes with "#ifdef _WIN64" so as to leave the 32-bit code 
unaffected.

--
Allin Cottrell
Department of Economics
Wake Forest University, NC