Test --compress-debug-sections with rust-lld.

Author: khuey

tests/run-make/rust-lld-compress-debug-sections/main.rs

@@ -0,0 +1,4 @@
+// Test linking using `cc` with `rust-lld`, using the unstable CLI described in MCP 510
+// see https://github.com/rust-lang/compiler-team/issues/510 for more info
+
+fn main() {}

tests/run-make/rust-lld-compress-debug-sections/rmake.rs

@@ -0,0 +1,38 @@
+// Checks the `compress-debug-sections` option on rust-lld.
+
+//@ needs-rust-lld
+//@ only-linux
+//@ ignore-cross-compile
+
+// FIXME: This test isn't comprehensive and isn't covering all possible combinations.
+
+use run_make_support::{assert_contains, cmd, llvm_readobj, run_in_tmpdir, rustc};
+
+fn check_compression(compression: &str, to_find: &str) {
+    run_in_tmpdir(|| {
+        let out = rustc()
+            .arg("-Zlinker-features=+lld")
+            .arg("-Clink-self-contained=+linker")
+            .arg("-Zunstable-options")
+            .arg("-Cdebuginfo=full")
+            .link_arg(&format!("-Wl,--compress-debug-sections={compression}"))
+            .input("main.rs")
+            .run_unchecked();
+        let stderr = out.stderr_utf8();
+        if stderr.is_empty() {
+            llvm_readobj().arg("-t").arg("main").run().assert_stdout_contains(to_find);
+        } else {
+            assert_contains(
+                stderr,
+                format!(
+                    "LLVM was not built with LLVM_ENABLE_{to_find} or did not find {compression} at build time"
+                ),
+            );
+        }
+    });
+}
+
+fn main() {
+    check_compression("zlib", "ZLIB");
+    check_compression("zstd", "ZSTD");
+}