osmaczko fa79b1c79c
chore(nim-bindings): replace dynlib dlopen with plain importc (#61)
* chore(nim-bindings): replace dynlib dlopen with plain importc

The dynlib pragma hard-coded a library path and resolved it via dlopen() at
runtime, preventing static linking and forcing a specific load-time path.
Using bare {.importc.} lets consumers choose: link liblibchat dynamically
at link time (--passL:-llibchat) or link it statically into their binary.

* Rust -> Nim ABI  (#62)

* Use correct build hook

* force sret like return from rust code for nim compatibility

* Fix target mismatch

* Update usages

* ci: add nim-bindings-test

* fix(nim-bindings): fix ABI mismatch in destroy_* FFI functions and add defer-based cleanup

Nim's C backend silently transforms large struct parameters (>16 bytes) into
pointer parameters when calling importc functions. The destroy_* functions were
declared taking T by value in Rust, but Nim always passed &T — causing Rust to
read garbage from the stack on x86-64 (SIGILL on CI) while accidentally working
on ARM64 macOS due to that ABI coincidentally also using pointers for large structs.

Fix by changing all destroy_* functions to take &mut T and using drop_in_place,
which is the correct idiom for dropping a value through a pointer.

On the Nim side, replace scattered manual destroy calls with defer, which
guarantees cleanup on all exit paths and prevents use-after-destroy bugs.

---------

Co-authored-by: Jazz Turner-Baggs <473256+jazzz@users.noreply.github.com>
2026-02-25 20:09:55 +01:00
..