Metrowerks compilers include optimization settings for size or speed, and various levels of optimization. Choose size as your desired outcome, and the level of optimization you wish to apply.

You control optimization settings as an option in the settings for your target. The option is in the Processor settings panel.

When debugging, compile your code without any optimizations. Some optimizations disrupt the relationship between source and object code required by the debugger. Optimize your code after you have finished debugging.

See also "Using C/C++ in the CodeWarrior IDE."