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Optimizing the Edit-Build-Debug Cycle

Xcode offers a number of features you can take advantage of to decrease build time for your project. For example, you can use distributed builds to shorten the time it takes to build your whole project or multiple projects. ZeroLink and predictive compilation, on the other hand, improve turnaround time for single file changes, thereby speeding up the edit–build–debug cycle. All of these features reduce the amount of time you spend idle while waiting for your project to build.

This chapter describes the following features:

• Precompiled prefix headers let you decrease the amount of time spent building compiling each source file in a target by specifying a single header file that includes all of the headers commonly used by the target’s files and compiling this header a single time.

• Predictive compilation reduces the time required to compile single file changes by beginning to compile a file while you are still editing it.

• Distributed builds can dramatically reduce build time for large projects by distributing compiles to available machines on the network.

Other features that you can use to optimize the edit-build-debug cycle include:

• Fix and Continue, described in “Using Fix and Continue,” improves your debugging efficiency by allowing you to make changes to your application and see the results of your modification without stopping your debugging session.

• ZeroLink, described in “Using ZeroLink,” shortens build time by eliminating the linking step for development builds.

Contents:

Using a Precompiled Prefix Header
Distributing Builds Among Multiple Computers
Predictive Compilation

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