Smart recompilation

With current compiler technology, changing a single line in a large software system may trigger massive recompilations. If the change occurs in a file with shared declarations, all compilation units depending upon that file must be recompiled to assure consistency. However, many of those recompilations may be redundant, because the change may affect only a small fraction of the overall system. Smart recompilation is a method for reducing the set of modules that must be recompiled after a change. The method determines whether recompilation is necessary by isolating the differences among program modules and analyzing the effect of changes. The method is applicable to languages with and without overloading. A prototype demonstrates that the method is efficient and can be added with modest effort to existing compilers.