Auto merge of #49289 - varkor:emit-metadata-without-link, r=michaelwoerister

Make --emit=metadata output metadata regardless of link

Fixes #40109. I'm not sure whether this condition was important here or not, but I can't see why it is required (removing it doesn't cause the error the comment warns about, so I'm assuming it's safe). If this is too heavy-handed, I can special-case on `OutputType::Metadata`.

r? @nrc

Author: bors

src/librustc_trans/back/link.rs

@@ -149,8 +149,9 @@ pub(crate) fn link_binary(sess: &Session,
     let mut out_filenames = Vec::new();
     for &crate_type in sess.crate_types.borrow().iter() {
         // Ignore executable crates if we have -Z no-trans, as they will error.
-        if (sess.opts.debugging_opts.no_trans ||
-            !sess.opts.output_types.should_trans()) &&
+        let output_metadata = sess.opts.output_types.contains_key(&OutputType::Metadata);
+        if (sess.opts.debugging_opts.no_trans || !sess.opts.output_types.should_trans()) &&
+           !output_metadata &&
            crate_type == config::CrateTypeExecutable {
             continue;
         }