ctor fails to trigger on MacOS with Cranelift codegen backend

[stewartadam]

On MacOS 15.5 with the cranelift codegen backend from rustc 1.90.0-nightly (a84ab0ce6 2025-07-06), #[ctor] does not trigger on module initialization. It seems to be limited to MacOS, I also tested on Linux with cranelift and it worked fine.

See also: dtolnay/typetag#35 (comment)

[mmastrac]

Does codegen-units=1 help? If not, does codegen-units=9999? This may be related to #280, or alternatively just a codegen backend issue.

[stewartadam]

Doesn't help, unfortunately.

[stewartadam]

Aha! Some more details in rust-lang/rustc_codegen_cranelift#1588 (comment) posted by bjorn3 -- looks like rust-ctor needs to add a flag for MacOS and cranelift needs to add support for it for this to work.