1 files changed, 89 insertions, 0 deletions
diff --git a/packages/Python/lldbsuite/test/functionalities/thread/create_during_step/main.cpp b/packages/Python/lldbsuite/test/functionalities/thread/create_during_step/main.cpp
new file mode 100644
index 000000000000..3a00248c022a
--- /dev/null
+++ b/packages/Python/lldbsuite/test/functionalities/thread/create_during_step/main.cpp
@@ -0,0 +1,89 @@
+//===-- main.cpp ------------------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// This test is intended to create a situation in which one thread will be
+// created while the debugger is stepping in another thread.
+
+#include <atomic>
+#include <thread>
+
+// Note that although hogging the CPU while waiting for a variable to change
+// would be terrible in production code, it's great for testing since it
+// avoids a lot of messy context switching to get multiple threads synchronized.
+#define do_nothing()
+
+#define pseudo_barrier_wait(bar) \
+    --bar;                       \
+    while (bar > 0)              \
+        do_nothing();
+
+#define pseudo_barrier_init(bar, count) (bar = count)
+
+std::atomic_int g_barrier;
+
+volatile int g_thread_created = 0;
+volatile int g_test = 0;
+
+void *
+step_thread_func ()
+{
+    g_test = 0;         // Set breakpoint here
+
+    while (!g_thread_created)
+        g_test++;
+
+    // One more time to provide a continue point
+    g_test++;           // Continue from here
+
+    // Return
+    return NULL;
+}
+
+void *
+create_thread_func (void *input)
+{
+    std::thread *step_thread = (std::thread*)input;
+
+    // Wait until the main thread knows this thread is started.
+    pseudo_barrier_wait(g_barrier);
+
+    // Wait until the other thread is done.
+    step_thread->join();
+
+    // Return
+    return NULL;
+}
+
+int main ()
+{
+    // Use a simple count to simulate a barrier.
+    pseudo_barrier_init(g_barrier, 2);
+
+    // Create a thread to hit the breakpoint.
+    std::thread thread_1(step_thread_func);
+
+    // Wait until the step thread is stepping
+    while (g_test < 1)
+        do_nothing();
+
+    // Create a thread to exit while we're stepping.
+    std::thread thread_2(create_thread_func, &thread_1);
+
+    // Wait until that thread is started
+    pseudo_barrier_wait(g_barrier);
+
+    // Let the stepping thread know the other thread is there
+    g_thread_created = 1;
+
+    // Wait for the threads to finish.
+    thread_2.join();
+    thread_1.join();
+
+    return 0;
+}