What is a Delphi DCU file?

Question

What is a Delphi DCU file?

I believe it stands for \"Delphi Compiled Unit\". Am I correct in assuming it contains object code, and therefore corresponds to an \".o\"

Answer 1

A Delphi Compiled Unit contains object code, and pre-compiled headers, and is therefore somewhat comparable to both an obj file and a .pch / .gch file.

The 'interface' section of a Delphi source file corresponds to the header, and the 'implementation' section creates the object code.

Pre-compiled header files may significantly reduce compilation and link time. The DCU header section provides link information to other referenced units, that does not have to be re-discovered.

In the Delphi / Turbo Pascal environment, pre-compiled headers support strict type checking, which would have required source-code referencing if an Object file format like .coff or .obj had been used. (In C++, name mangling provides a similar but less complete function).