Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/openmp/runtime/test/ompt/misc/unset_callback.c

@@ -0,0 +1,29 @@
+// RUN: %libomp-compile-and-run | FileCheck %s
+// REQUIRES: ompt
+#include "callback.h"
+#include <omp.h>
+
+int main()
+{
+  #pragma omp parallel num_threads(1)
+  {
+
+  }
+  ompt_set_callback(ompt_callback_parallel_begin, NULL);
+  #pragma omp parallel num_threads(1)
+  {
+
+  }
+
+  // Check if libomp supports the callbacks for this test.
+  // CHECK-NOT: {{^}}0: Could not register callback 'ompt_callback_idle'
+
+  // CHECK: 0: NULL_POINTER=[[NULL:.*$]]
+
+  // CHECK: {{^}}[[THREAD_ID:[0-9]+]]: ompt_event_parallel_begin:
+  // CHECK: {{^}}[[THREAD_ID]]: ompt_event_parallel_end:
+  // CHECK-NOT: {{^}}[[THREAD_ID]]: ompt_event_parallel_begin:
+  // CHECK: {{^}}[[THREAD_ID]]: ompt_event_parallel_end:
+
+  return 0;
+}