Index: lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
===================================================================
--- lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
+++ lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
@@ -1062,6 +1062,8 @@
     if (action == nullptr) {
       LLDB_LOG(log, "no action specified for pid {0} tid {1}", GetID(),
                thread->GetID());
+      // Make sure we reset the stop reason for all the threads.
+      static_cast<NativeThreadLinux &>(*thread).ResetStopReason();
       continue;
     }
 
Index: lldb/source/Plugins/Process/Linux/NativeThreadLinux.h
===================================================================
--- lldb/source/Plugins/Process/Linux/NativeThreadLinux.h
+++ lldb/source/Plugins/Process/Linux/NativeThreadLinux.h
@@ -94,6 +94,8 @@
 
   void SetStopped();
 
+  void ResetStopReason();
+
   // Member Variables
   lldb::StateType m_state;
   ThreadStopInfo m_stop_info;
Index: lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
===================================================================
--- lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
+++ lldb/source/Plugins/Process/Linux/NativeThreadLinux.cpp
@@ -396,7 +396,10 @@
 
 void NativeThreadLinux::SetStoppedWithNoReason() {
   SetStopped();
+  ResetStopReason();
+}
 
+void NativeThreadLinux::ResetStopReason() {
   m_stop_info.reason = StopReason::eStopReasonNone;
   m_stop_info.details.signal.signo = 0;
 }
Index: lldb/test/API/functionalities/thread/break_step_other/Makefile
===================================================================
--- /dev/null
+++ lldb/test/API/functionalities/thread/break_step_other/Makefile
@@ -0,0 +1,4 @@
+CXX_SOURCES := main.cpp
+ENABLE_THREADS := YES
+
+include Makefile.rules
Index: lldb/test/API/functionalities/thread/break_step_other/TestThreadBreakStepOther.py
===================================================================
--- /dev/null
+++ lldb/test/API/functionalities/thread/break_step_other/TestThreadBreakStepOther.py
@@ -0,0 +1,68 @@
+"""
+Test stop reasons after hitting and deleting a breakpoint and
+stepping another thread. Scenario:
+  - run two threads
+  - stop one thread at a breakpoint
+  - delete the breakpoint
+  - single step the other thread
+The thread stopped at the deleted breakpoint should have stop reason
+'none'.
+"""
+
+
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class ThreadBreakStepOtherTestCase(TestBase):
+    mydir = TestBase.compute_mydir(__file__)
+
+    def test_hit_breakpoint_delete_step_other_thread(self):
+        self.main_source_file = lldb.SBFileSpec("main.cpp")
+        self.build()
+        (target, process, thread, breakpoint) = lldbutil.run_to_source_breakpoint(
+            self, "// break here", self.main_source_file, only_one_thread = False)
+
+        # Make sure both threads reach the breakpoint so that we are
+        # sure both threads started. Also remember the thread that is
+        # stopped at the breakpoint and the other thread.
+        stopped_threads = lldbutil.get_threads_stopped_at_breakpoint(
+            process, breakpoint)
+        if len(stopped_threads) == 1:
+            other_thread = stopped_threads[0]
+            process.Continue()
+            stopped_threads = lldbutil.get_threads_stopped_at_breakpoint(
+                process, breakpoint)
+            self.assertEquals(
+                1,
+                len(stopped_threads),
+                "only one thread expected stopped at breakpoint")
+            breakpoint_thread = stopped_threads[0]
+        else:
+            self.assertEquals(
+                2,
+                len(stopped_threads),
+                "unexpected number of threads stopped at breakpoint")
+            other_thread = stopped_threads[0]
+            breakpoint_thread = stopped_threads[1]
+
+        target.BreakpointDelete(breakpoint.GetID())
+
+        other_thread.StepInstruction(False)
+
+        reason = other_thread.GetStopReason()
+        self.assertEqual(
+            lldb.eStopReasonPlanComplete,
+            reason,
+            "Expected thread stop reason 'plancomplete', but got '%s'" %
+            lldbutil.stop_reason_to_str(reason))
+
+        reason = breakpoint_thread.GetStopReason()
+        self.assertEqual(
+            lldb.eStopReasonNone,
+            reason,
+            "Expected thread stop reason 'none', but got '%s'" %
+            lldbutil.stop_reason_to_str(reason))
Index: lldb/test/API/functionalities/thread/break_step_other/main.cpp
===================================================================
--- /dev/null
+++ lldb/test/API/functionalities/thread/break_step_other/main.cpp
@@ -0,0 +1,20 @@
+#include <thread>
+
+volatile int g_test = 0;
+
+void thread_func () {
+    g_test = 0;  // break here
+
+    while (true) {
+      g_test++;
+    }
+}
+
+int main () {
+    std::thread thread_1(thread_func);
+    std::thread thread_2(thread_func);
+
+    thread_1.join();
+    thread_2.join();
+    return 0;
+}