Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/libunwind/test/libunwind_02.pass.cpp

@@ -0,0 +1,38 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <unwind.h>
+
+#define EXPECTED_NUM_FRAMES 50
+#define NUM_FRAMES_UPPER_BOUND 100
+
+_Unwind_Reason_Code callback(_Unwind_Context *context, void *cnt) {
+  (void)context;
+  int *i = (int *)cnt;
+  ++*i;
+  if (*i > NUM_FRAMES_UPPER_BOUND) {
+    abort();
+  }
+  return _URC_NO_REASON;
+}
+
+void test_backtrace() {
+  int n = 0;
+  _Unwind_Backtrace(&callback, &n);
+  if (n < EXPECTED_NUM_FRAMES) {
+    abort();
+  }
+}
+
+int test(int i) {
+  if (i == 0) {
+    test_backtrace();
+    return 0;
+  } else {
+    return i + test(i - 1);
+  }
+}
+
+int main() {
+  int total = test(50);
+  assert(total == 1275);
+}