visibility.h File Reference

Imported symbol visibility. More...

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Macros
#define	UDIPE_PUBLIC

Detailed Description

This project uses GCC's -fvisibility=hidden model, i.e. all functions which are not marked as public are not exported from the library, which improves linker and library performance.

Functions which are marked as extern are excluded from this mechanism, but they must also go through the ELF PLT to allow linker overriding, which means that internal calls from udipe are pessimized to take the same path as external calls from outside udipe.

Therefore, a third visibility mode is needed for functions which are used by udipe internally and by external clients of udipe. And enforcing this visibility is the job of UDIPE_PUBLIC.

Macro Definition Documentation

UDIPE_PUBLIC

#define UDIPE_PUBLIC

Mark a function declaration as public

This is used to annotate which functions are meant to be used by udipe end users, which has the following consequences:

• On GNU platforms, we switch back from the hidden visibility model to the default visibility model so that the function can be used externally.
• On Windows, we declare the functions as externally available from a DLL.