# Compile time m68k CPU selection

The m68k family has a few backward incompatibilities that forces us to select a
target CPU at compile time, notably because of cache control mechanisms.

Unless I've missed something, it's impossible to generate a piece of native code
that can clear the instruction cache on both the M68040 and the M68030.

Hence the unit at [xcomp/m68k/cpusel.fs]. It provides useful macros like
"clearcache," and a way to select a target CPU, which changes how those macros
behave.

The default target CPU is the M68040.

## API

selectM68030
selectM68040 ( -- )
  Select a target CPU.

clearache, ( -- )
  Compile native code that clears both the data and instruction cache.
