[GR-66932] Avoid sending empty kwargs dicts to native

PullRequest: graalpython/3881

Author: msimacek

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/capi/ExternalFunctionNodes.java

@@ -983,7 +983,7 @@ protected Object[] prepareCArguments(VirtualFrame frame) {
             Object[] args = readVarargsNode.executeObjectArray(frame);
             PKeyword[] kwargs = readKwargsNode.executePKeyword(frame);
             PythonLanguage language = getLanguage(PythonLanguage.class);
-            return new Object[]{self, createArgsTupleNode.execute(language, args, seenNativeArgsTupleStorage), PFactory.createDict(language, kwargs)};
+            return new Object[]{self, createArgsTupleNode.execute(language, args, seenNativeArgsTupleStorage), kwargs.length > 0 ? PFactory.createDict(language, kwargs) : PNone.NO_VALUE};
         }
 
         @Override
@@ -1106,7 +1106,7 @@ protected Object[] prepareCArguments(VirtualFrame frame) {
             args = PythonUtils.arrayCopyOfRange(args, 1, args.length);
             PKeyword[] kwargs = readKwargsNode.executePKeyword(frame);
             PythonLanguage language = getLanguage(PythonLanguage.class);
-            return new Object[]{self, createArgsTupleNode.execute(language, args, seenNativeArgsTupleStorage), PFactory.createDict(language, kwargs)};
+            return new Object[]{self, createArgsTupleNode.execute(language, args, seenNativeArgsTupleStorage), kwargs.length > 0 ? PFactory.createDict(language, kwargs) : PNone.NO_VALUE};
         }
     }
 

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/type/slots/TpSlotVarargs.java

@@ -322,7 +322,7 @@ static Object callNative(VirtualFrame frame, TpSlotCExtNative slot, Object self,
             PythonLanguage language = context.getLanguage(inliningTarget);
             PythonThreadState state = getThreadStateNode.execute(inliningTarget, context);
             PTuple argsTuple = createArgsTupleNode.execute(inliningTarget, language, args, eagerTupleState);
-            Object kwargsDict = PFactory.createDict(language, keywords);
+            Object kwargsDict = keywords.length > 0 ? PFactory.createDict(language, keywords) : NO_VALUE;
             Object nativeResult = externalInvokeNode.call(frame, inliningTarget, state, C_API_TIMING, name, slot.callable,
                             toNativeNode.execute(self), toNativeNode.execute(argsTuple), toNativeNode.execute(kwargsDict));
             eagerTupleState.report(inliningTarget, argsTuple);