The KAP preprocessor determines whether the host architecture
is ev4 or ev5 and then optimizes your
program for that architecture by default. In the event you compile
a program on one architecture but plan to run it on another,
override the default by setting /tune equal to the
architecture where the program will run. For example, if you compile
a program on ev4 architecture, but plan to run it on
ev5 , use /tune=ev5 .