RB_GC_GUARD support or something else to ensure VALUE is on the stack

[uvlad7]

This macro is used to protect VALUEs from being GC-ed while they are still in use indirectly (or even directly, as otherwise it may be placed in a register, not on the stack). If for some reason it's not possible to use RB_GC_GUARD from memory.h, another solutions probably exist, as it's a common problem when interacting with conservative GCs. And I believe it should be mentioned in the readme.

[uvlad7]

UPD: it says registers are ok in ruby, but RB_GC_GUARD is still needed in some cases

[sue445]

I see. I'll try to figure out if it is possible to automatically generate bindings for C macros.

[uvlad7]

You may want to look how it's done in rb-sys
As for macro parsing, maybe rbgccxml is worth a look? Won't work out of the box, but may inspire ruby_header_parser

[uvlad7]

Stumbled upon Python's cffi, it uses pycparser - common approach is to preprocess headers with cpp and feed them into cffi - and thought maybe it's worth to use it here too.

Also, I have a question about compatibility, where will it fail if a signature of a function is changed or it's removed completely? For example, Rust rb-sys uses bindgen during gem compilation, so if a function is changed/removed, later usages will become invalid and it'll fail. Important part here is that it uses exactly the same header that is used by regular C native extensions. But I guess Go will use a pregenated version, right, which contains definitions parsed from ruby.h? If so, it'll fail on link time if the function is deleted and probably on run time if signature is changed.