[cmake-developers] Find module problems

[Bill Hoffman]

So, a number of modules have been updated and variable names have been 
changed.  To maintain backwards compatibility with the old stuff a set 
has been used to set the new variable.  The problem is many automatic 
builds are setup to pre-load the cache or specify a value on the command 
line.  An example is FindCurses.cmake:

The old one set:
CURSES_LIBRARY

The build script for CMake on Linux sets a cache value for 
CURSES_LIBRARY.  But, the new FindCurses.cmake does this:

   SET(CURSES_LIBRARY "${CURSES_CURSES_LIBRARY}")

Which of course does not work.

So, for backwards compatibility with Find stuff, cache variables can not 
be changed into regular variables.

-Bill