The present invention provides a method to optimize object code files produced by a compiler for several different types of target processors. The compiler divides the source code to be compiled into several functional modules. Given a specified set of target processors, each functional module is compiled resulting in a target object version for each target processor. Then, for each functional module, a merging process is performed wherein identical target object versions or target object versions with similar contents are merged by deleting the identical or similar versions. After this merging process, a composite object code file is formed containing all of the non-deleted target object versions of the function modules.