Don't perform the optimisation on arguments

Author: nielsdos

Zend/Optimizer/dfa_pass.c

@@ -1092,12 +1092,10 @@ static void zend_dfa_optimize_send_copies(zend_op_array *op_array, zend_ssa *ssa
 
 		int ssa_cv = ssa_op->op1_use;
 
-#if 0
 		/* Argument move must not be observable in backtraces */
 		if (ssa->vars[ssa_cv].var < op_array->num_args) {
 			continue;
 		}
-#endif
 
 		/* Unsetting a CV is always fine if it gets overwritten afterwards.
 		 * Since type inference often infers very wide types, we are very loose in matching types. */