constants. The default is currently 32 bits/single, which corresponds
    to the old behaviour (constants which cannot be exactly represented
    in the default/chosen precision will also still be automatically
    upgraded to higher precision). Supported constructs:
   * Command line switch -CF<x>
   * Compiler directive {$MINFPCONSTPREC <x>}
  whereby in both cases <x> can be default, 32 or 64. 80 is not supported
  because there is no generic way to figure out whether the current target
  actually supports 80 bit precision floating point calculations while
  parsing the command line switches (pbestreal can still change in case of
  win64 or -Cfsse2)

git-svn-id: trunk@8349 -