diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -2908,8 +2908,12 @@
       if (ch == 'm') {
         do {
           auto pid_tid = response.GetPidTid(LLDB_INVALID_PROCESS_ID);
+          // If we get an invalid response, break out of the loop.
+          // If there are valid tids, they have been added to ids.
+          // If there are no valid tids, we'll fall through to the
+          // bare-iron target handling below.
           if (!pid_tid)
-            return {};
+            break;
 
           ids.push_back(pid_tid.getValue());
           ch = response.GetChar(); // Skip the command separator
diff --git a/lldb/test/API/functionalities/gdb_remote_client/TestThreadInfoTrailingComma.py b/lldb/test/API/functionalities/gdb_remote_client/TestThreadInfoTrailingComma.py
new file mode 100644
--- /dev/null
+++ b/lldb/test/API/functionalities/gdb_remote_client/TestThreadInfoTrailingComma.py
@@ -0,0 +1,27 @@
+import lldb
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test.decorators import *
+from gdbclientutils import *
+
+
+class TestThreadInfoTrailingComma(GDBRemoteTestBase):
+
+    def test(self):
+        class MyResponder(MockGDBServerResponder):
+            def haltReason(self):
+                return "T02thread:1"
+
+            def qfThreadInfo(self):
+                return "m1,2,3,4,"
+
+        self.server.responder = MyResponder()
+        target = self.dbg.CreateTarget('')
+        if self.TraceOn():
+          self.runCmd("log enable gdb-remote packets")
+          self.addTearDownHook(
+                lambda: self.runCmd("log disable gdb-remote packets"))
+        process = self.connect(target)
+        self.assertEqual(process.GetThreadAtIndex(0).GetThreadID(), 1)
+        self.assertEqual(process.GetThreadAtIndex(1).GetThreadID(), 2)
+        self.assertEqual(process.GetThreadAtIndex(2).GetThreadID(), 3)
+        self.assertEqual(process.GetThreadAtIndex(3).GetThreadID(), 4)