precompiled headers - Is it OK to remove Prefix.pch file from the Xcode project?

Question

The Xcode project generates Prefix.pch file automatically. When I deleted this file and tried to build, I got build error saying '*_Prefix.pch' file is missing.

• Is Prefix.pch file is a must for compiling with Xcode?
• How can I build without the Prefix.pch file?

Answer 1

In Xcode, go to your target's build settings (Command-Option-E, build tab) and uncheck Precompile Prefix Header (GCC_PRECOMPILE_PREFIX_HEADER). You can also remove the value of the Prefix Header setting if you wish.

Prefix headers are compiled and stored in a cache, and then automatically included in every file during compilation. This can speed up compilation, and lets you include a file without adding an import statement to every file using it. They are not required, and actually slow compilation whenever you change them.