handle core dumps output in qemu user mode

In addition to the whole-system emulation/virtualization, QEMU also
supports user-mode emulation, where the emulation happens as a normal
process inside the parent system. This allows running most tests by
simply spawning remote-test-server inside user-mode emulation.

Unfortunately, QEMU always writes its own message in addition to the
system one when a core dump happens, which breaks a few tests which
match on the exact output of the system.

This PR changes those tests to strip the (possible) QEMU output before
checking if the output is expected.

1 files changed, 8 insertions, 3 deletions

diff --git a/src/test/ui/runtime/rt-explody-panic-payloads.rs b/src/test/ui/runtime/rt-explody-panic-payloads.rs
index e2221e5df8e..755d3df42de 100644
--- a/src/test/ui/runtime/rt-explody-panic-payloads.rs
+++ b/src/test/ui/runtime/rt-explody-panic-payloads.rs
@@ -22,7 +22,12 @@ fn main() {
     }.expect("running the command should have succeeded");
     println!("{:#?}", output);
     let stderr = std::str::from_utf8(&output.stderr);
-    assert!(stderr.map(|v| {
-        v.ends_with("fatal runtime error: drop of the panic payload panicked\n")
-    }).unwrap_or(false));
+    assert!(stderr
+        .map(|v| {
+            // When running inside QEMU user-mode emulation, there will be an extra message printed
+            // by QEMU in the stderr whenever a core dump happens. Remove it before the check.
+            v.strip_suffix("qemu: uncaught target signal 6 (Aborted) - core dumped\n").unwrap_or(v)
+        })
+        .map(|v| { v.ends_with("fatal runtime error: drop of the panic payload panicked\n") })
+        .unwrap_or(false));
 }