This would solve half my problem. Can I always trust that? I've been told before that everytime a C function returns a struct it is actually returning a pointer, but I wasn't able to find that written in stone
That's because it isn't true. In fact one of the classical ways for a C function to return a struct is to be *GIVEN* a pointer, e.g., (...)
Sure, sorry. I should have said that the C functions fill memory from a given pointer.
and obviously a C compiler is entitled to return a small struct in registers if it feels like it.
If a compiler is compiling code that calls a library, how is it supposed to know if a return pointer is been passed as a register or by using a pointer? The compiler may not have access to the built library to check that. (Begginer question, I never wrote assembly code.) Thanks, Maurício