Overview - Compiling

Before a program can be run, it has to be converted from source code to executable code. The Compiler can produce various forms of executable code directly, or it can create object code. Object code is not executable, and has to be linked to the run-time system to create an executable file. The Compiler has two phases: one for checking the program syntax and one for generating native machine code.

By default, the Compiler compiles your program without any intervention. You can configure the project to be built in a specific way, such as specifying types of target files to build, the target platform and so on.

By default, your project is built automatically, every time you save the project. This ensures that whenever a resource changes, an incremental build starts and all resources modified since the last build are rebuilt. You can force a manual build too, by cleaning the project.

You can configure the compilation using the following techniques:

• Build Configurations. You specify the build settings in either the project language settings or the build configuration.
• Compiler directives. You can control the way programs are compiled by using Compiler directives.
• Copybook locations. You can specify the location of the copybooks that your program refers to, if you keep them in different directories from the program.
• Temporary files used during compilation. Before compiling, you must ensure there is enough free space for the Compiler's temporary work files. You can specify the location where the Compiler puts its temporary files.
• Techniques for compiling quickly. Large applications comprising many programs can take significant time to compile. You can use various techniques to increase the speed of compilation.

The Compiler records errors with severity levels ranging from information messages to fatal errors which stop the Compiler working.