RFC: replace static member CBs with extern C proxies?

[epruesse]

​http://stackoverflow.com/questions/2068022/in-c-is-it-safe-portable-to-use-static-member-function-pointer-for-c-api-call

In summary: calling static member functions isn't allowed by the standard. It does work for GCC and CLANG, though.

What do we do?

1. ignore this and implement in whatever way we feel like on a given day
2. move towards static or extern "c" functions
3. move towards static member functions

[epruesse]

Regarding type-safe callbacks:

1. Executing a function call that has less arguments than the CB spec is ok in C. It's done a lot e.g. in glib. The surplus arguments end up on the stack and are overwritten, but that doesn't matter.
2. For type safe C++ callbacks there are libraries, e.g. boost::signal or libsigc++. They are significantly slower than raw C callbacks (libsigc++ seems to be faster than boost::signal), so I don't think it's a good idea for interaction. But for GUI callbacks it should be ok.

What do you guys think? Use libsigc++ in WINDOW?

[westram]

I don't see the point.. is anything broken?