1 files changed, 57 insertions, 0 deletions
diff --git a/library/backtrace/crates/line-tables-only/src/lib.rs b/library/backtrace/crates/line-tables-only/src/lib.rs
new file mode 100644
index 000000000..bd5afcb3a
--- /dev/null
+++ b/library/backtrace/crates/line-tables-only/src/lib.rs
@@ -0,0 +1,57 @@
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+    use backtrace::Backtrace;
+    use libc::c_void;
+
+    pub type Callback = extern "C" fn(data: *mut c_void);
+
+    extern "C" {
+        fn foo(cb: Callback, data: *mut c_void);
+    }
+
+    extern "C" fn store_backtrace(data: *mut c_void) {
+        let bt = backtrace::Backtrace::new();
+        unsafe { *(data as *mut Option<Backtrace>) = Some(bt) };
+    }
+
+    fn assert_contains(backtrace: &Backtrace,
+                       expected_name: &str,
+                       expected_file: &str,
+                       expected_line: u32) {
+
+        let expected_file = Path::new(expected_file);
+
+        for frame in backtrace.frames() {
+            for symbol in frame.symbols() {
+                if let Some(name) = symbol.name() {
+                    if name.as_bytes() == expected_name.as_bytes() {
+                        assert!(symbol.filename().unwrap().ends_with(expected_file));
+                        assert_eq!(symbol.lineno(), Some(expected_line));
+                        return;
+                    }
+                }
+            }
+        }
+
+        panic!("symbol {:?} not found in backtrace: {:?}", expected_name, backtrace);
+    }
+
+    /// Verifies that when debug info includes only lines tables the generated
+    /// backtrace is still generated successfully. The test exercises behaviour
+    /// that failed previously when compiling with clang -g1.
+    ///
+    /// The test case uses C rather than rust, since at that time when it was
+    /// written the debug info generated at level 1 in rustc was essentially
+    /// the same as at level 2.
+    #[test]
+    #[cfg_attr(windows, ignore)]
+    fn backtrace_works_with_line_tables_only() {
+        let mut backtrace: Option<Backtrace> = None;
+        unsafe { foo(store_backtrace, &mut backtrace as *mut _ as *mut c_void) };
+        let backtrace = backtrace.expect("backtrace");
+        assert_contains(&backtrace, "foo", "src/callback.c", 13);
+        assert_contains(&backtrace, "bar", "src/callback.c", 9);
+        assert_contains(&backtrace, "baz", "src/callback.c", 5);
+    }
+}