Skip linking if it is not required

[ojeda]

This allows to use --emit=metadata,obj and other metadata + non-link combinations.

Fixes #81117.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @ecstatic-morse (or someone else) soon.

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[ojeda]

The added should_link() looked like the right local fix, but someone with more knowledge around other should_codegen() callers should probably take a look.

[nagisa]

This seems reasonable enough. Thank you!

@bors r+

[bors]

📌 Commit b7ba8b8c50367d43d930d86902f3fc3af9b2943f has been approved by nagisa

[rust-log-analyzer]

The job mingw-check failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

configure: rust.channel         := nightly
configure: rust.debug-assertions := True
configure: llvm.assertions      := True
configure: dist.missing-tools   := True
configure: build.configure-args := ['--enable-sccache', '--disable-manage-submodu ...
configure: writing `config.toml` in current directory
configure: 
configure: run `python /checkout/x.py --help`
configure: 
---
skip untracked path cpu-usage.csv during rustfmt invocations
skip untracked path src/doc/book/ during rustfmt invocations
skip untracked path src/doc/rust-by-example/ during rustfmt invocations
skip untracked path src/llvm-project/ during rustfmt invocations
Diff in /checkout/compiler/rustc_codegen_ssa/src/back/link.rs at line 123:
             };
 
 
-            if sess.opts.output_types.should_link()
-                && !preserve_objects_for_their_debuginfo(sess)
-            {
+            if sess.opts.output_types.should_link() && !preserve_objects_for_their_debuginfo(sess) {
                 for module in &codegen_results.modules {
                     remove_temps_from_module(module);
                 }
Running `"/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/rustfmt" "--config-path" "/checkout" "--edition" "2018" "--unstable-features" "--skip-children" "--check" "/checkout/compiler/rustc_codegen_ssa/src/back/link.rs"` failed.
If you're running `tidy`, try again with `--bless`. Or, if you just want to format code, run `./x.py fmt` instead.
Build completed unsuccessfully in 0:00:14

[ojeda]

Thanks to you! That was a quick review. :)

Fixed the formatting.

[nagisa]

@bors r+

[bors]

📌 Commit f9275e1 has been approved by nagisa

[bors]

⌛ Testing commit f9275e1 with merge a4cbb44...

[bors]

☀️ Test successful - checks-actions
Approved by: nagisa
Pushing a4cbb44 to master...