By applying an ill-advised methodology developed by inferior minds in the 1980ies to deal with incompatible operating systems from narrowminded vendors, AutoCrap[tm] is guaranteed to turn even the most portable source code into a unportable mess.
AutoCrap[tm] employs a plethora of checks for features no longer in existence on any running operating system, even if your software package does not actually come close to using that feature.
By turning all AutoCrap[tm] infected sortware packages into totally unreadable messes of #ifdefs, AutoCrap[tm] will seem like the only feasible way to write portable code.
Upon seeing AutoCrap[tm] for the first time 99 out of 100 users or programmers out there will cry out in despair “This portability thing looks SOOO hard, thank goodness for AutoCrap[tm]”
AutoCrap[tm] sports an infection of options which nobody, including the AutoCrap[tm] developers, can give any good reason why you might want to apply, but even so, these options provide the 100% sure defence: “You just need to set the right options” against any people in a fit of insight or even actually wisdom might claim that AutoCrap[tm] actually decreases software portability.
AutoCrap[tm] – because we otherwise anybody could port software!