Nightly introduces new warning when print-native-static-libs a rlib crate

[amyspark]

Hi @lu-zero ,

rust-lang/rust#138139 introduced a new warning:

warning: cannot output linkage information without staticlib crate-type

note: consider --crate-type staticlib to print linkage information

We're getting these in gst-plugin-webrtc-signalling-protocol and gst-plugin-version-helper, both of which are not crates which output libraries.

I don't know if there's a way to not introspect these, perhaps you know better than me?

[lu-zero]

We may skip printing native-static-libs when the crate-type doesn't include staticlib, but sounds fishy...

[workingjubilee]

Hmm. Am I misunderstanding things, or do you control the --crate-type the code is invoked with? Is there a particular goal in mind here for --print native-static-libs when you aren't passing --crate-type=staticlib?

[amyspark]

IIRC builds that do not specify --crate-type will build both staticlib and cdylib. In that case the output of native-static-libs is meant to go into the contents of Libs.private.

In my experience with macOS, however, for cdylib crates (where I got the warning to fire) it is good practice to also list any relevant -framework requirements. That covers downstream consumers that may be using Apple frameworks through the ABI without an #import for them beforehand.

[workingjubilee]

Exciting!

Well, --print native-static-libs is specifically and only for a fairly narrow use-case, it is not necessarily a complete listing for any other crate type. Why it was designed that way I am not sure of, but as mentioned, the warning was not incorrect, just... a bother.

[lu-zero]

Having a --print native-libs would also quite nice here, but ...