🍒 [lldb] Clear Frames when changing disable-language-runtime-unwindplans (#151208)

lldb/include/lldb/Target/Process.h

@@ -98,6 +98,7 @@ class ProcessProperties : public Properties {
   void SetStopOnSharedLibraryEvents(bool stop);
   bool GetDisableLangRuntimeUnwindPlans() const;
   void SetDisableLangRuntimeUnwindPlans(bool disable);
+  void DisableLanguageRuntimeUnwindPlansCallback();
   bool GetDetachKeepsStopped() const;
   void SetDetachKeepsStopped(bool keep_stopped);
   bool GetWarningsOptimization() const;

lldb/source/Target/Process.cpp

@@ -207,6 +207,9 @@ ProcessProperties::ProcessProperties(lldb_private::Process *process)
     m_collection_sp->SetValueChangedCallback(
         ePropertyPythonOSPluginPath,
         [this] { m_process->LoadOperatingSystemPlugin(true); });
+    m_collection_sp->SetValueChangedCallback(
+        ePropertyDisableLangRuntimeUnwindPlans,
+        [this] { DisableLanguageRuntimeUnwindPlansCallback(); });
   }
 
   m_experimental_properties_up =
@@ -321,6 +324,15 @@ void ProcessProperties::SetDisableLangRuntimeUnwindPlans(bool disable) {
   m_process->Flush();
 }
 
+void ProcessProperties::DisableLanguageRuntimeUnwindPlansCallback() {
+  if (!m_process)
+    return;
+  for (auto thread_sp : m_process->Threads()) {
+    thread_sp->ClearStackFrames();
+    thread_sp->DiscardThreadPlans(/*force*/ true);
+  }
+}
+
 bool ProcessProperties::GetDetachKeepsStopped() const {
   const uint32_t idx = ePropertyDetachKeepsStopped;
   return GetPropertyAtIndexAs<bool>(

lldb/test/API/lang/swift/async/unwind/disable_language_unwinder/Makefile

@@ -0,0 +1,3 @@
+SWIFT_SOURCES := main.swift
+SWIFTFLAGS_EXTRAS := -parse-as-library
+include Makefile.rules

lldb/test/API/lang/swift/async/unwind/disable_language_unwinder/TestDisableLanguageUnwinder.py

@@ -0,0 +1,25 @@
+import lldb
+from lldbsuite.test.decorators import *
+import lldbsuite.test.lldbtest as lldbtest
+import lldbsuite.test.lldbutil as lldbutil
+
+class TestDisableLanguageUnwinder(lldbtest.TestBase):
+
+    @swiftTest
+    @skipIf(oslist=['windows', 'linux'])
+    def test(self):
+        """Test async unwind"""
+        self.build()
+        src = lldb.SBFileSpec('main.swift')
+        target, process, thread, bkpt = lldbutil.run_to_source_breakpoint(
+            self, 'break here', src)
+
+        self.assertIn("syncFunc", thread.GetFrameAtIndex(0).GetFunctionName())
+        self.assertIn("callSyncFunc", thread.GetFrameAtIndex(1).GetFunctionName())
+        self.assertIn("main", thread.GetFrameAtIndex(2).GetFunctionName())
+
+        self.runCmd("settings set target.process.disable-language-runtime-unwindplans true")
+
+        self.assertIn("syncFunc", thread.GetFrameAtIndex(0).GetFunctionName())
+        self.assertIn("callSyncFunc", thread.GetFrameAtIndex(1).GetFunctionName())
+        self.assertNotIn("main", thread.GetFrameAtIndex(2).GetFunctionName())

lldb/test/API/lang/swift/async/unwind/disable_language_unwinder/main.swift

@@ -0,0 +1,13 @@
+func syncFunc() {
+  print("break here")
+}
+
+func callSyncFunc() async {
+  syncFunc()
+}
+
+@main struct Main {
+  static func main() async {
+    await callSyncFunc()
+  }
+}