Fix a bug in OPTForCausalLM where self.lm_head is the wrong size

aiserver.py

@@ -1293,6 +1293,25 @@ if(not vars.use_colab_tpu and vars.model not in ["InferKit", "Colab", "OAI", "Go
                 pass
 
 
+        # Fix a bug in OPTForCausalLM where self.lm_head is the wrong size
+        if(transformers_version == "4.19.0"):
+            try:
+                from transformers import OPTForCausalLM, OPTModel
+            except ImportError:
+                pass
+            else:
+                # This is the same as the original __init__ but with
+                # config.hidden_size
+                # replaced with
+                # config.word_embed_proj_dim
+                def new_init(self, config):
+                    super(OPTForCausalLM, self).__init__(config)
+                    self.model = OPTModel(config)
+                    self.lm_head = torch.nn.Linear(config.word_embed_proj_dim, config.vocab_size, bias=False)
+                    self.post_init()
+                OPTForCausalLM.__init__ = new_init
+
+
         # Patch transformers to use our custom logit warpers
         from transformers import LogitsProcessorList, LogitsWarper, LogitsProcessor, TopKLogitsWarper, TopPLogitsWarper, TemperatureLogitsWarper, RepetitionPenaltyLogitsProcessor
         from warpers import AdvancedRepetitionPenaltyLogitsProcessor, TailFreeLogitsWarper, TypicalLogitsWarper