Hi, Sergey,

thanks for the patch! LGTM

Sergey

On 5/30/26 19:04, Sergey Kaplun wrote:
> From: Mike Pall <mike>
>
> Thanks to Sergey Kaplun.
>
> (cherry picked from commit b925b3e3fc6771171602323b45fbe9fb8fc90369)
>
> This patch fixes the regression in the arm64 OSX FFI behaviour when the
> fundamental C types are passed via the stack. The given arguments should
> occupy the "packed" size on the stack if they are fundamental C
> types [1]. Structures require the pointer-size alignment like it was done
> in the previous commit. This patch fixes that (not only for enums but for
> other data types too). This fixes the tests that were failing after the
> previous commit.
>
> [1]:https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms#Pass-arguments-to-functions-correctly
>
> Sergey Kaplun:
> * added the description for the problem
>
> Part of tarantool/tarantool#12480
> ---
>   src/lj_ccall.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/lj_ccall.c b/src/lj_ccall.c
> index 1beccc10..7c3ec1e5 100644
> --- a/src/lj_ccall.c
> +++ b/src/lj_ccall.c
> @@ -1082,7 +1082,7 @@ static int ccall_set_args(lua_State *L, CTState *cts, CType *ct,
>       if (CCALL_ALIGN_STACKARG) {  /* Align argument on stack. */
>         MSize align = (1u << ctype_align(ccall_struct_align(cts, d))) - 1;
>   #if LJ_TARGET_ARM64 && LJ_TARGET_OSX
> -      isva = 1;
> +      isva = ctype_isstruct(d->info);
>   #endif
>         if (rp || (CCALL_PACK_STACKARG && isva && align < CTSIZE_PTR-1))
>   	align = CTSIZE_PTR-1;