Rollup merge of rust-lang#126534 - Rejyr:comment-section-migration, r…

…=jieyouxu

Migrate `run-make/comment-section` to `rmake.rs`

Part of rust-lang#121876.

r? ``@jieyouxu``

try-job: x86_64-msvc
try-job: aarch64-gnu
try-job: aarch64-apple

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -10,7 +10,6 @@ run-make/c-unwind-abi-catch-panic/Makefile
 run-make/cat-and-grep-sanity-check/Makefile
 run-make/cdylib-dylib-linkage/Makefile
 run-make/cdylib-fewer-symbols/Makefile
-run-make/comment-section/Makefile
 run-make/compiler-lookup-paths-2/Makefile
 run-make/compiler-lookup-paths/Makefile
 run-make/compiler-rt-works-on-mingw/Makefile

tests/run-make/comment-section/rmake.rs

@@ -0,0 +1,47 @@
+// Both GCC and Clang write by default a `.comment` section with compiler information.
+// Rustc received a similar .comment section, so this tests checks that this section
+// properly appears.
+// See https://github.com/rust-lang/rust/commit/74b8d324eb77a8f337b35dc68ac91b0c2c06debc
+
+//@ only-linux
+// FIXME(jieyouxu): check cross-compile setup
+//@ ignore-cross-compile
+
+use std::path::PathBuf;
+
+use run_make_support::llvm_readobj;
+use run_make_support::rustc;
+use run_make_support::{cwd, env_var, read_dir, run_in_tmpdir};
+
+fn main() {
+    let target = env_var("TARGET");
+
+    rustc()
+        .arg("-")
+        .stdin("fn main() {}")
+        .emit("link,obj")
+        .arg("-Csave-temps")
+        .target(&target)
+        .run();
+
+    // Check linked output has a `.comment` section with the expected content.
+    llvm_readobj()
+        .section(".comment")
+        .input("rust_out")
+        .run()
+        .assert_stdout_contains("rustc version 1.");
+
+    // Check all object files (including temporary outputs) have a `.comment`
+    // section with the expected content.
+    read_dir(cwd(), |f| {
+        if !f.extension().is_some_and(|ext| ext == "o") {
+            return;
+        }
+
+        llvm_readobj()
+            .section(".comment")
+            .input(&f)
+            .run()
+            .assert_stdout_contains("rustc version 1.");
+    });
+}