Enable cross compilation on run-make/relro-levels

tests/run-make/branch-protection-check-IBT/Makefile

@@ -7,6 +7,12 @@ include ../tools.mk
 
 # only-x86_64
 
+# ignore-test
+# FIXME(jieyouxu): This test never runs because the `ifeq` check on line 17
+# compares `x86` to `x86_64`, which always evaluates to false.
+# When the test does run, the compilation does not include `.note.gnu.property`.
+# See https://github.com/rust-lang/rust/pull/126720 for more information.
+
 all:
 ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86_64)
 	$(RUSTC) --target x86_64-unknown-linux-gnu -Z cf-protection=branch -L$(TMPDIR) -C link-args='-nostartfiles'  -C save-temps  ./main.rs -o $(TMPDIR)/rsmain

tests/run-make/branch-protection-check-IBT/_rmake.rs

@@ -0,0 +1,31 @@
+// Check for GNU Property Note
+
+// How to run this
+// python3 x.py test --target x86_64-unknown-linux-gnu  tests/run-make/branch-protection-check-IBT/
+
+//@ only-x86_64
+
+//@ ignore-test
+// FIXME(jieyouxu): see the FIXME in the Makefile
+
+use run_make_support::llvm_readobj;
+use run_make_support::rustc;
+use run_make_support::{cwd, env_var};
+
+fn main() {
+    let llvm_components = env_var("LLVM_COMPONENTS");
+    if !format!(" {llvm_components} ").contains(" x86 ") {
+        return;
+    }
+
+    rustc()
+        .input("main.rs")
+        .target("x86_64-unknown-linux-gnu")
+        .arg("-Zcf-protection=branch")
+        .arg(format!("-L{}", cwd().display()))
+        .arg("-Clink-args=-nostartfiles")
+        .arg("-Csave-temps")
+        .run();
+
+    llvm_readobj().arg("-nW").input("main").run().assert_stdout_contains(".note.gnu.property");
+}