Can the gcc static linker properly inline functions from a static library?

If we compile a num开发者_运维百科ber of source codes which makes uses of a static library named lib.a, would the inline functions in lib.a get properly inlined with the rest of binaries?

no, they would not. Inlining is an operation on the parse tree and requires access to the source code for both the host and donor sources of the inlined code.

Static libraries have already been compiled from source to binary at the point you use them, so inlining cannot happen.

However, code that is not inlined is also 'proper' and will function just fine (assuming it got compiled into the static library at all).

Well, since in order to even attempt to call an inline function its declaration must be visible at the call site. If it is then inline then the compiler will either inline it or completely ignore the request.

If you are wondering if functions NOT declared inline that were inlined in the library can then also be inlined when you link to the final product...this would depend on the implementation and, assuming it is already capable of LTO (since it did it to the library), it very well might be able to inline them again. You may be required to cause the implementation to include the definition even when it's been inlined everywhere though...all depends on the implementation.

http://crazyeddiecpp.blogspot.com/2010/12/inline-functions-and-you.html