cxxrtl: add missing extern "C".

This bug was hidden if a header was generated.

diff --git a/backends/cxxrtl/cxxrtl_backend.cc b/backends/cxxrtl/cxxrtl_backend.cc
index 5e5ba5ac0f04f3b7f58b2b64eadc96ff4b821b46..6d3c2f4f9b78af29783ba00d15ebc2f1b457f82b 100644 (file)
--- a/backends/cxxrtl/cxxrtl_backend.cc
+++ b/backends/cxxrtl/cxxrtl_backend.cc
@@ -1935,6 +1935,7 @@ struct CxxrtlWorker {
                f << "} // namespace " << design_ns << "\n";
                f << "\n";
                if (top_module != nullptr && debug_info) {
+                       f << "extern \"C\"\n";
                        f << "cxxrtl_toplevel " << design_ns << "_create() {\n";
                        inc_indent();
                                std::string top_type = design_ns + "::" + mangle(top_module);