Port backtrace-rs's cpp_smoke_test to rustc repo

Author: Pyr0de

Diff for: tests/run-make/backtrace-cpp-smoke-test/cpp_smoke_test/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "cpp_smoke_test"
+version = "0.1.0"
+authors = ["Nick Fitzgerald <[email protected]>"]
+edition = "2021"
+build = "build.rs"
+
+[build-dependencies]
+cc = "1.0"
+
+[dependencies]
+backtrace = { version = "0.3.74", features = ["cpp_demangle"] }

Diff for: tests/run-make/backtrace-cpp-smoke-test/cpp_smoke_test/build.rs

@@ -0,0 +1,14 @@
+fn main() {
+    compile_cpp();
+}
+
+fn compile_cpp() {
+    println!("cargo:rerun-if-changed=cpp/trampoline.cpp");
+
+    cc::Build::new()
+        .cpp(true)
+        .debug(true)
+        .opt_level(0)
+        .file("cpp/trampoline.cpp")
+        .compile("libcpptrampoline.a");
+}

Diff for: tests/run-make/backtrace-cpp-smoke-test/cpp_smoke_test/cpp/trampoline.cpp

@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+namespace space {
+    template <typename FuncT>
+    void templated_trampoline(FuncT func) {
+        func();
+    }
+}
+
+typedef void (*FuncPtr)();
+
+extern "C" void cpp_trampoline(FuncPtr func) {
+    space::templated_trampoline(func);
+}

Diff for: tests/run-make/backtrace-cpp-smoke-test/cpp_smoke_test/tests/smoke.rs

@@ -0,0 +1,67 @@
+use std::sync::atomic::{AtomicBool, Ordering};
+
+extern "C" {
+    fn cpp_trampoline(func: extern "C" fn()) -> ();
+}
+
+#[test]
+fn smoke_test_cpp() {
+    static RAN_ASSERTS: AtomicBool = AtomicBool::new(false);
+
+    extern "C" fn assert_cpp_frames() {
+        let mut physical_frames = Vec::new();
+        backtrace::trace(|cx| {
+            physical_frames.push(cx.ip());
+
+            // We only want to capture this closure's frame, assert_cpp_frames,
+            // space::templated_trampoline, and cpp_trampoline. Those are
+            // logical frames, which might be inlined into fewer physical
+            // frames, so we may end up with extra logical frames after
+            // resolving these.
+            physical_frames.len() < 5
+        });
+
+        let names: Vec<_> = physical_frames
+            .into_iter()
+            .flat_map(|ip| {
+                let mut logical_frame_names = vec![];
+
+                backtrace::resolve(ip, |sym| {
+                    let sym_name = sym.name().expect("Should have a symbol name");
+                    let demangled = sym_name.to_string();
+                    logical_frame_names.push(demangled);
+                });
+
+                assert!(
+                    !logical_frame_names.is_empty(),
+                    "Should have resolved at least one symbol for the physical frame"
+                );
+
+                logical_frame_names
+            })
+            // Skip the backtrace::trace closure and assert_cpp_frames, and then
+            // take the two C++ frame names.
+            .skip_while(|name| !name.contains("trampoline"))
+            .take(2)
+            .collect();
+
+        println!("actual names = {names:#?}");
+
+        let expected =
+            ["void space::templated_trampoline<void (*)()>(void (*)())", "cpp_trampoline"];
+        println!("expected names = {expected:#?}");
+
+        assert_eq!(names.len(), expected.len());
+        for (actual, expected) in names.iter().zip(expected.iter()) {
+            assert_eq!(actual, expected);
+        }
+
+        RAN_ASSERTS.store(true, Ordering::SeqCst);
+    }
+
+    assert!(!RAN_ASSERTS.load(Ordering::SeqCst));
+    unsafe {
+        cpp_trampoline(assert_cpp_frames);
+    }
+    assert!(RAN_ASSERTS.load(Ordering::SeqCst));
+}

Diff for: tests/run-make/backtrace-cpp-smoke-test/rmake.rs

@@ -0,0 +1,23 @@
+// Part of porting backtrace-rs tests to rustc repo:
+// Original test: <https://github.com/rust-lang/rust/issues/122899>
+// <https://github.com/rust-lang/backtrace-rs/tree/6fa4b85b9962c3e1be8c2e5cc605cd078134152b/crates/cpp_smoke_test>
+// Issue: https://github.com/rust-lang/rust/issues/122899
+// ignore-tidy-linelength
+
+use std::path::PathBuf;
+
+use run_make_support::{cargo, cmd, env_var, path, target};
+
+const CRATE: &str = "cpp_smoke_test";
+
+fn main() {
+    std::env::set_current_dir(CRATE).unwrap();
+
+    let target_dir = path("target");
+
+    cargo()
+        .args(&["test", "--target", &target()])
+        .env("CARGO_TARGET_DIR", &target_dir)
+        .run()
+        .assert_exit_code(0);
+}