What Can be Precompiled. NXP CodeWarrior Development Studio

Chapter 17

Precompiling

Each time you invoke the CodeWarrior compiler to translate a source code file, it

preprocesses

the file to prepare its contents for translation. Preprocessing tasks include expanding macros, removing comments, and including header files. If many source code files include the same large or complicated header file, the compiler must preprocess it each time it is included. Repeatedly preprocessing this header file can take up a large portion of the time that the compiler operates.

To shorten the time spent compiling a project, CodeWarrior compilers can precompile a file once instead of preprocessing it every time it is included in project source files. When it precompiles a header file, the compiler converts the file's contents into internal data structures, then writes this internal data to a precompiled file. Conceptually, precompiling records the compiler's state after the preprocessing step and before the translation step of the compilation process.

This section shows you how to use and create precompiled files:

•

What Can be Precompiled

•

Using a Precompiled File

•

Creating a Precompiled File

17.1 What Can be Precompiled

A file to be precompiled does not have to be a header file (

.h

or

.hpp

files, for example), but it must meet these requirements:

• The file must be a source code file in text format.

You cannot precompile libraries or other binary files.

• Precompiled files must have a

.mch

filename extension.

• The file must not contain any statements that generate data or executable code.

CodeWarrior Development Studio for Power Architecture Processors Build Tools Reference Manual, Rev.

10.6, 02/2014

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