[generate] fix default autocompile case on gpu (#37756)

src/transformers/generation/utils.py

@@ -3430,7 +3430,8 @@ class GenerationMixin:
         model_kwargs = self._get_initial_cache_position(input_ids, model_kwargs)
 
         model_forward = self.__call__
-        if self._valid_auto_compile_criteria(model_kwargs, generation_config):
+        compile_forward = self._valid_auto_compile_criteria(model_kwargs, generation_config)
+        if compile_forward:
             os.environ["TOKENIZERS_PARALLELISM"] = "0"
             model_forward = self.get_compiled_call(generation_config.compile_config)
 

src/transformers/modeling_utils.py

@@ -5270,6 +5270,7 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin, PushToHubMixin, PeftAdapterMi
         # Only reset it if not present or different from previous config
         if "llama4" in self.config.model_type:  # TODO try to enable for FULL COMPILE HYBRID CACHE SUPPORT
             return self.__call__
+        compile_config = compile_config or CompileConfig()
         default_config = getattr(self.generation_config, "compile_config", None) or CompileConfig()
         if (
             not hasattr(self, "_compiled_call")