Add post-dist test for checking that we use LLD

And remove the previous beta/stable/nightly LLD tests.

Author: Kobzol

src/tools/opt-dist/src/tests.rs

@@ -104,7 +104,10 @@ llvm-config = "{llvm_config}"
             "tests/incremental",
             "tests/mir-opt",
             "tests/pretty",
+            // Make sure that we don't use too new GLIBC symbols on x64
             "tests/run-make/glibc-symbols-x86_64-unknown-linux-gnu",
+            // Make sure that we use LLD by default on x64
+            "tests/run-make/rust-lld-x86_64-unknown-linux-gnu-dist",
             "tests/ui",
             "tests/crashes",
         ];

tests/run-make/rust-lld-by-default-beta-stable/main.rs

@@ -1,17 +1,14 @@
-// Ensure that rust-lld is used as the default linker on `x86_64-unknown-linux-gnu` on the nightly
-// channel, and that it can also be turned off with a CLI flag.
+// Ensure that rust-lld is used as the default linker on `x86_64-unknown-linux-gnu`
+// dist artifacts and that it can also be turned off with a CLI flag.
 
-//@ needs-rust-lld
-//@ ignore-beta
-//@ ignore-stable
+//@ only-dist
 //@ only-x86_64-unknown-linux-gnu
 
 use run_make_support::linker::{assert_rustc_doesnt_use_lld, assert_rustc_uses_lld};
 use run_make_support::rustc;
 
 fn main() {
-    // A regular compilation should use rust-lld by default. We'll check that by asking the linker
-    // to display its version number with a link-arg.
+    // A regular compilation should use rust-lld by default.
     assert_rustc_uses_lld(rustc().input("main.rs"));
 
     // But it can still be disabled by turning the linker feature off.

tests/run-make/rust-lld-by-default-beta-stable/rmake.rs

@@ -0,0 +1,5 @@
+// Test linking using `cc` with `rust-lld`, which is on by default on the x86_64-unknown-linux-gnu
+// target.
+// See https://github.com/rust-lang/compiler-team/issues/510 for more info
+
+fn main() {}

tests/run-make/rust-lld-by-default-nightly/main.rs renamed to tests/run-make/rust-lld-x86_64-unknown-linux-gnu-dist/main.rs

@@ -0,0 +1,20 @@
+// Ensure that rust-lld is used as the default linker on `x86_64-unknown-linux-gnu`
+// and that it can also be turned off with a CLI flag.
+//
+// This version of the test checks that LLD is used by default when LLD is enabled in the
+// toolchain. There is a separate test that checks that LLD is used for dist artifacts
+// unconditionally.
+
+//@ needs-rust-lld
+//@ only-x86_64-unknown-linux-gnu
+
+use run_make_support::linker::{assert_rustc_doesnt_use_lld, assert_rustc_uses_lld};
+use run_make_support::rustc;
+
+fn main() {
+    // A regular compilation should use rust-lld by default.
+    assert_rustc_uses_lld(rustc().input("main.rs"));
+
+    // But it can still be disabled by turning the linker feature off.
+    assert_rustc_doesnt_use_lld(rustc().arg("-Zlinker-features=-lld").input("main.rs"));
+}