Xcode6 why kill PCH (Precompile Prefix Header) & how to add a PCH file

Reprint: http://blog.csdn.net/iosdevtip/article/details/40918353

has been developed with XCODE6, but the project is created on the XCODE5, so has not noticed, Xcode6 unexpectedly killed PCH file.

Why does Xcode6 not create PCH files automatically?

Simply look: When we write the project, most of the macro definition, header file Import are here, Xcode6 remove Precompile Prefix header is the main reason may be Prefix header greatly increased the time of build. Without the prefix header, manual @import will be manually imported to the header file, losing programming convenience while reducing the build time. Specific reasons

The discussion on the StackOverflow has been more clear.

StackOverflow: Why does Xcode6 not create PCH files automatically?

How do I add a PCH (precompile Prefix Header) to Xcode6?

1,command+n, open the new File window: ios->other->pch file, create a PCH document: "Project name-prefix.pch":

2, add the path to the precompile header option in building setting "$ (srcroot)/project name/PCH filename" (For example: $ (srcroot)/lotteryfive/ LOTTERYFIVE-PREFIX.PCH)

Yes, compile the program, if you have an error check the path you added is correct.

3, precompile Prefix header is yes, pre-compiled PCH file will be cached, can improve the speed of compilation

Xcode6 why kill PCH (Precompile Prefix Header) & how to add a PCH file