> > But then inlining / cloning is no longer cheap, no? And will be > disabled at -O2?
If you declare it "inline" and not "static inline" it will be inlined pretty much as before, only it will get unified if it ends up out of line in multiple units. Main difference in between static and non-static is in logic deciding when inlining into all callers will lead to removing the offline copy from the program. This is controlable by comdat-sharing-probability parameter. We won't clone at -O2 unless we know code will shrink that may be something to revisit. I think it would be resonable to enable clonning at -O2 for functions declared inline. I was also playing with idea adding a GCC decision to function mangling, so comdat clones can be inlined. I.e. having something like mangled_foo->mangled_foo.__gcc_cprop_clone.arg0_0.arg1_17 It would need to invent unique textual representations of all/most our substitutions that can get tricky. Honza
