test warning about known issue 79555 with lld

Author: lqd

src/test/ui/linkers/mentions_issue_79555.rs

@@ -0,0 +1,11 @@
+// build-pass
+// needs-profiler-support
+// needs-rust-lld
+// compile-flags: -C linker-flavor=gcc:lld -Z unstable-options -Clink-self-contained=y -Cinstrument-coverage
+
+// Test ensuring that a warning referencing lld known issue 79555 is emitted when:
+// - we're asking to use lld, via the enriched gcc linker-flavor
+// - the CRT object linking is on
+// - either coverage or generating a profile is requested
+
+fn main() {}

src/test/ui/linkers/mentions_issue_79555.stderr

@@ -0,0 +1,4 @@
+warning: Using `lld`, self-contained linking, and coverage or profile generation has known issues. See issue #79555 for more details, at https://github.com/rust-lang/rust/issues/79555
+
+warning: 1 warning emitted
+