fix(native): preserve failed LLDB launch ownership and exit proof

Publish failed-launch process identity and observed exit separately from object validity. Retire only the exact owned process and retain uncertainty when exit cannot be established.

Refs: #4232

bridge/native/rea_lldb_tracer.py

@@ -555,6 +555,38 @@ def _failed_launch_description(process):
     return None
 
 
+def _retire_failed_launch(process, config, listener, stdout, stderr):
+    """Reconcile an SBProcess returned alongside a failed Launch error."""
+    if not process.IsValid():
+        stdout.close()
+        stderr.close()
+        return False
+
+    pid = process.GetProcessID()
+    if pid > 0:
+        # Even an already-exited process needs its PID published so the host
+        # can distinguish a completed launch failure from an unknown target.
+        with open(config["pid_path"], "w") as handle:
+            handle.write(str(pid))
+
+    if process.GetState() != lldb.eStateExited:
+        stdout.mark_launched()
+        stderr.mark_launched()
+        if pid > 0:
+            # Hold a surviving target until the host has captured its start
+            # identity. If that proof is unavailable, Kill still addresses
+            # this exact SBProcess created by the current launch request.
+            _wait_for_identity_ack(config)
+        process.Kill()
+        _wait_for_exit(listener, process, 5)
+
+    exit_observed = process.GetState() == lldb.eStateExited
+    expected_exit = exit_observed
+    stdout.close(expected_exit=expected_exit)
+    stderr.close(expected_exit=expected_exit)
+    return exit_observed
+
+
 def trace(debugger, config):
     global _TRACE_CONTEXT
     debugger.SetAsync(True)
@@ -630,8 +662,9 @@ def trace(debugger, config):
             )
         process = target.Launch(_launch_info(target, config, listener), error)
         if not error.Success() or not process.IsValid():
-            stdout.close()
-            stderr.close()
+            exit_observed = _retire_failed_launch(
+                process, config, listener, stdout, stderr
+            )
             return {
                 "status": "launch-error",
                 "error": error.GetCString(),
@@ -640,15 +673,26 @@ def trace(debugger, config):
                     if process.IsValid()
                     else {}
                 ),
+                **(
+                    {"target_process_exit_observed": True}
+                    if exit_observed
+                    else {}
+                ),
             }
         launch_failure = _failed_launch_description(process)
         if launch_failure is not None:
-            stdout.close(expected_exit=True)
-            stderr.close(expected_exit=True)
+            exit_observed = _retire_failed_launch(
+                process, config, listener, stdout, stderr
+            )
             return {
                 "status": "launch-error",
                 "error": launch_failure,
                 "target_process_created": True,
+                **(
+                    {"target_process_exit_observed": True}
+                    if exit_observed
+                    else {}
+                ),
             }
         stdout.mark_launched()
         stderr.mark_launched()

bridge/native/test_rea_lldb_tracer.py

@@ -15,6 +15,8 @@ fake_lldb = sys.modules.setdefault("lldb", types.ModuleType("lldb"))
 fake_lldb.LLDB_INVALID_ADDRESS = -1
 fake_lldb.eLaunchFlagDebug = 2
 fake_lldb.eLaunchFlagStopAtEntry = 4
+fake_lldb.eStateExited = 10
+fake_lldb.SBEvent = lambda: object()
 spec = importlib.util.spec_from_file_location(
     "rea_lldb_tracer", os.path.join(os.path.dirname(__file__), "rea_lldb_tracer.py")
 )
@@ -23,6 +25,136 @@ spec.loader.exec_module(tracer)
 
 
 class NativeTraceBudgetTests(unittest.TestCase):
+    def test_failed_launch_does_not_infer_exit_from_a_failed_kill(self):
+        class Process:
+            def IsValid(self):
+                return True
+
+            def GetProcessID(self):
+                return 12345
+
+            def GetState(self):
+                return 6
+
+            def Kill(self):
+                return None
+
+        class Sink:
+            close_exit = None
+
+            def mark_launched(self):
+                pass
+
+            def close(self, expected_exit=False):
+                self.close_exit = expected_exit
+
+        with tempfile.TemporaryDirectory() as directory:
+            stdout, stderr = Sink(), Sink()
+            with patch.object(tracer, "_wait_for_identity_ack", return_value="unavailable"), patch.object(
+                tracer, "_wait_for_exit", return_value=None
+            ):
+                exited = tracer._retire_failed_launch(
+                    Process(), {"pid_path": os.path.join(directory, "pid")}, object(), stdout, stderr
+                )
+        self.assertFalse(exited)
+        self.assertFalse(stdout.close_exit)
+        self.assertFalse(stderr.close_exit)
+
+    def test_failed_launch_publishes_pid_and_retires_live_process(self):
+        class Process:
+            state = 6
+            killed = False
+
+            def IsValid(self):
+                return True
+
+            def GetProcessID(self):
+                return 12345
+
+            def GetState(self):
+                return self.state
+
+            def Kill(self):
+                self.killed = True
+                self.state = tracer.lldb.eStateExited
+
+        class Sink:
+            launched = False
+            close_exit = None
+
+            def mark_launched(self):
+                self.launched = True
+
+            def close(self, expected_exit=False):
+                self.close_exit = expected_exit
+
+        with tempfile.TemporaryDirectory() as directory:
+            pid_path = os.path.join(directory, "pid")
+            process = Process()
+            stdout, stderr = Sink(), Sink()
+
+            def acknowledge(config):
+                with open(config["pid_path"], "r") as pid_file:
+                    self.assertEqual(pid_file.read(), "12345")
+                return "readable"
+
+            with patch.object(tracer, "_wait_for_identity_ack", acknowledge):
+                exited = tracer._retire_failed_launch(
+                    process,
+                    {"pid_path": pid_path},
+                    object(),
+                    stdout,
+                    stderr,
+                )
+
+        self.assertTrue(exited)
+        self.assertTrue(process.killed)
+        self.assertTrue(stdout.launched)
+        self.assertTrue(stderr.launched)
+        self.assertTrue(stdout.close_exit)
+        self.assertTrue(stderr.close_exit)
+
+    def test_failed_launch_records_when_valid_process_is_already_exited(self):
+        class Process:
+            def IsValid(self):
+                return True
+
+            def GetProcessID(self):
+                return 12345
+
+            def GetState(self):
+                return tracer.lldb.eStateExited
+
+            def Kill(self):
+                raise AssertionError("an exited process must not be killed")
+
+        class Sink:
+            close_exit = None
+
+            def mark_launched(self):
+                raise AssertionError("an exited process has no output to drain")
+
+            def close(self, expected_exit=False):
+                self.close_exit = expected_exit
+
+        with tempfile.TemporaryDirectory() as directory:
+            pid_path = os.path.join(directory, "pid")
+            stdout, stderr = Sink(), Sink()
+            with patch.object(
+                tracer,
+                "_wait_for_identity_ack",
+                side_effect=AssertionError("exit is already observed"),
+            ):
+                exited = tracer._retire_failed_launch(
+                    Process(), {"pid_path": pid_path}, object(), stdout, stderr
+                )
+            with open(pid_path, "r") as pid_file:
+                self.assertEqual(pid_file.read(), "12345")
+
+        self.assertTrue(exited)
+        self.assertTrue(stdout.close_exit)
+        self.assertTrue(stderr.close_exit)
+
     def test_pre_target_integrity_failure_reports_no_process_created(self):
         original_debugger = getattr(tracer.lldb, "SBDebugger", None)
 

docs/native-investigation.md

@@ -451,6 +451,9 @@ The run ends when the process exits, `max_events` entries are recorded,
 Bounded termination reports partial coverage. REA checks process termination
 using a launch-time OS start identity; if ownership or cleanup cannot be
 verified, the result or error preserves that uncertainty. The result reports:
+Launch errors keep the fact that LLDB created a process separate from whether
+it remains alive. An exited `SBProcess` is reported as exited only after LLDB
+confirms that state; unresolved ownership remains retained for cleanup retry.
 
 - the outcome, exit status and captured stdout/stderr (1 MiB kept per stream
   while excess bytes are drained and counted without growing capture files).

src/native/LldbCallTracer.ts

@@ -124,6 +124,7 @@ const tracerOutputSchema = z.discriminatedUnion("status", [
     ]),
     error: z.string().nullable(),
     target_process_created: z.boolean().optional(),
+    target_process_exit_observed: z.boolean().optional(),
   }),
 ]);
 
@@ -421,11 +422,16 @@ export class LldbCallTracer implements NativeCallTracer {
       exited.kind === "exited"
         ? await readTracerOutput(paths.result)
         : undefined;
-    let targetTermination: TargetTermination = exited.targetLaunched
-      ? await ensureTerminated(paths.pid, exited.targetIdentity, true)
-      : "terminated";
-    // Only an explicit bridge phase fact may prove that no target process was
-    // created. A missing PID or an integrity-error status alone is ambiguous.
+    // An explicit bridge observation can prove no process was created or that
+    // the created process exited. A missing PID alone remains ambiguous.
+    const bridgeObservedExit =
+      output !== undefined &&
+      output.status !== "traced" &&
+      output.target_process_exit_observed === true;
+    let targetTermination: TargetTermination =
+      exited.targetLaunched && !bridgeObservedExit
+        ? await ensureTerminated(paths.pid, exited.targetIdentity, true)
+        : "terminated";
     if (
       output !== undefined &&
       output.status !== "traced" &&

tests/boundary/providers/native/lldbCallTracerFailures.test.ts

@@ -277,6 +277,45 @@ describe("LLDB pre-target phase proof", () => {
 });
 
 describe("LLDB retains ambiguous target ownership", () => {
+  it("releases a launch failure after the bridge proves the process exited", async () => {
+    let configPath: string | undefined;
+    const tracer = new LldbCallTracer(
+      {},
+      async (_executable, arguments_) => {
+        const resolved = await configFromArguments(arguments_);
+        configPath = resolved.configPath;
+        await writeFile(
+          resolved.config.result_path,
+          JSON.stringify({
+            status: "launch-error",
+            error: "attach failed after the launched process exited",
+            target_process_created: true,
+            target_process_exit_observed: true,
+          }),
+        );
+        return {
+          kind: "exited",
+          targetLaunched: true,
+          exitCode: 1,
+          output: "",
+          targetIdentity: undefined,
+          cleanupFailure: undefined,
+        };
+      },
+      async () => ok(fakeTool),
+    );
+
+    const result = await tracer.trace(request);
+    if (result.ok) throw new Error("expected LLDB launch failure");
+    expect(projectAnalysisError(result.error).code).toBe(
+      "capability_unavailable",
+    );
+    expect(result.error.cleanup).toBeUndefined();
+    expect(configPath).toBeDefined();
+    if (configPath !== undefined)
+      await expect(access(dirname(configPath))).rejects.toThrow();
+  });
+
   it("keeps a post-target integrity rejection unresolved when its PID is missing", async () => {
     let runtime: string | undefined;
     const tracer = new LldbCallTracer(