include file

[Pierre A. Humblet]

I am compiling an application that uses both jpeg
and X11. As jpeg now comes with Cygwin, the Makefile
looks for includes in /usr/include 

Unfortunately /usr/include has an X11 subdirectory 
with files (such as Xlib.h) incompatible with Xfree.
As a result my application crashes. 
Now that I have identified the problem I can work around it.

Still this raises two questions
1) Why does cygwin need /usr/include/X11 (seems to come from gdb & tcltk)?
2) Assuming it's needed, why can't the files be the same as for xfree.

Pierre