Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

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

@@ -0,0 +1,8 @@
+#include <assert.h>
+#include <libunwind.h>
+
+int main() {
+  unw_context_t context;
+  int ret = unw_getcontext(&context);
+  assert(ret == UNW_ESUCCESS);
+}