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.

  However, the file may define static data.

• Precompiled header files for different IDE build targets are not interchangeable.