In verbose level 2, errors returned by libdw are reported in most cases,
but not when calling dwfl_attach_state.
Since elfutils v 0.160 (2014), dwfl_attach_state sets the error code to
report failure cause. On failure, log the reported error.
---
tools/perf/util/unwind-libdw.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c
index 1e9c974faf67..967323c958fd 100644
--- a/tools/perf/util/unwind-libdw.c
+++ b/tools/perf/util/unwind-libdw.c
@@ -236,7 +236,8 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
if (err)
goto out;
- if (!dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui))
+ err = !dwfl_attach_state(ui->dwfl, EM_NONE, thread->tid, &callbacks, ui);
+ if (err)
goto out;
err = dwfl_getthread_frames(ui->dwfl, thread->tid, frame_callback, ui);
--
2.13.6