Compiler-Generated Files The first time you build an application or a package, the compiler produces a compiled unit file (.dcu on Win32, .dcuil
on .NET) for each new unit used in your project; all the .dcu/.dcuil files in your project are then linked to create a
single executable or shared package. The first time you build a package, the compiler produces a file for each new
unit contained in the package, and then creates both a .dcp and a package file.If you use the GD switch, the linker
generates a map file and a .drc file; the .drc file, which contains string resources, can be compiled into a resource file.
When you build a project, individual units are not recompiled unless their source (.pas) files have changed since the
last compilation, their .dcu/.dpu files cannot be found, you explicitly tell the compiler to reprocess them, or the
interface of the unit depends on another unit which has been changed. In fact, it is not necessary for a unit's source
file to be present at all, as long as the compiler can find the compiled unit file and that unit has no dependencies on
other units that have changed.