compile: allow empty filename

src/codegen/codegen.cpp

@@ -116,7 +116,7 @@ SourceInfo::SourceInfo(BoxedModule* m, ScopingAnalysis* scoping, FutureFlags fut
       ast(ast),
       cfg(NULL),
       body(std::move(body)) {
-    assert(fn->size());
+    assert(fn);
     // TODO: we should track this reference correctly rather than making it a root
     gc::registerPermanentRoot(fn, true);
     this->fn = fn;

src/runtime/objmodel.cpp

@@ -2642,7 +2642,7 @@ extern "C" bool nonzero(Box* obj) {
                        || obj->cls == capifunc_cls || obj->cls == builtin_function_or_method_cls
                        || obj->cls == method_cls || obj->cls == frame_cls || obj->cls == generator_cls
                        || obj->cls == capi_getset_cls || obj->cls == pyston_getset_cls || obj->cls == wrapperdescr_cls
-                       || obj->cls == wrapperobject_cls,
+                       || obj->cls == wrapperobject_cls || obj->cls == code_cls,
                    "%s.__nonzero__", getTypeName(obj)); // TODO
 
             if (rewriter.get()) {

test/tests/compile_test.py

@@ -20,6 +20,9 @@ exec compile('print(1, 2)', 'test.py', 'exec')
 tree = compile('print(1, 2)', 'test.py', 'exec', _ast.PyCF_ONLY_AST)
 exec compile(tree, '<tree>', 'exec')
 
+c = compile('print(1, 2)', '', 'exec')
+exec c
+print(c.co_name, c.co_filename)
 
 # test bad syntax which should not raise in compile time:
 try: