Messages in this thread |  | | | Date | Wed, 24 Feb 2010 11:38:22 +0100 | | From | Clemens Ladisch <> | | Subject | Re: QUERY: Inclusion of header files in kernel header files |
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Theodore Tso wrote: > Also, it's highly desirable that as much as possible multiple > inclusion is fixed up at the same time you add extra #includes into > header files. Protecting against multiple inclusion is critical, > yes, but even with the protection against multiple inclusion, the > header file has to get parsed a second time, and that slows down > kernel compiles.
Multiple inclusion of a protected header does not hurt at all; gcc detects that a header file uses #ifdef/#endif header guards and automatically ignores any #include for that file if the symbol is already defined.
Regards, Clemens
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