创建静态和共享C ++库

Question

I'd like to build both static and shared libraries in a project.

I know that shared libraries need to be be created from objects compiled with -fpic to get Position Independent Code while the static library doesn't need this. This is all fine and I can create either a shared or static library.

I wouldn't want to compile my source twice to get the different object files, so how is this usually done? I read how to get a shared library based on a static one . However, the example shows the static library being built with -fpic. Is this the way to go? Are there things to be aware of with this?

Is there a common approach to compiling both static and shared libraries? Eg first static and based on the lib a shared version is created?

I'm interested to know if there are different approaches for this and what to consider when selecting.

I'm using gcc4.4 on Linux.

Thanks in advance!

Answer 1

The common approach that I've seen is, in fact, compiling your source twice , once with PIC and once without. If you don't do that, you either wind up with PIC overhead in the static library, or a shared object that can't be relocated by the OS (effectively meaning it's NOT shared across multiple clients of the library).