Improve tear-down process slightly

Since we are putting more things in the IC gc references,
call GC again after clearing them.

src/asm_writing/rewriter.cpp

@@ -1435,8 +1435,7 @@ void Rewriter::commit() {
 
     for (auto p : gc_references) {
         if (Py_REFCNT(p) == 1) {
-            // we hold the only ref to this object
-            assert(0 && "untested");
+            // we hold the only ref to this object, there's no way this could succeed in the future
 
             this->abort();
             return;

src/runtime/types.cpp

@@ -3955,6 +3955,10 @@ static int type_traverse(PyTypeObject* type, visitproc visit, void* arg) {
     Py_VISIT(type->tp_bases);
     Py_VISIT(type->tp_base);
 
+    // TODO: should have something like this to traverse GC references in the type runtime ICs:
+    // if (type->hasnext_ic)
+    // Py_TRAVERSE(*type->hasnext_ic);
+
     /* There's no need to visit type->tp_subclasses or
        ((PyHeapTypeObject *)type)->ht_slots, because they can't be involved
        in cycles; tp_subclasses is a list of weak references,
@@ -4719,6 +4723,8 @@ extern "C" void Py_Finalize() noexcept {
 
     // May need to run multiple collections to collect everything:
     while (true) {
+        clearAllICs();
+
         int freed = 0;
         freed += PyGC_Collect();
 
@@ -4738,7 +4744,6 @@ extern "C" void Py_Finalize() noexcept {
     }
     constant_locations.clear();
 
-    clearAllICs();
     PyType_ClearCache();
     PyOS_FiniInterrupts();
     _PyCodecRegistry_Deinit();
@@ -4752,6 +4757,7 @@ extern "C" void Py_Finalize() noexcept {
     constants.clear();
 
     clearAllICs();
+    PyGC_Collect();
 
     for (auto b : late_constants) {
         Py_DECREF(b);

src/runtime/util.cpp

@@ -251,7 +251,7 @@ extern "C" void dumpEx(void* p, int levels) {
             FunctionMetadata* md = f->md;
             if (md->source) {
                 printf("User-defined function '%s'\n", md->source->getName()->c_str());
-                printf("Defined at %s:%d\n", md->source->getFn()->c_str(), md->source->getBody()[0]->lineno);
+                printf("Defined at %s:%d\n", md->source->getFn()->c_str(), md->source->ast->lineno);
 
                 if (md->source->cfg && levels > 0) {
                     md->source->cfg->print();