patch 7.4.1270

Problem:    Warnings for missing values in switch.
Solution:   Change switch to if-else or add values.

src/if_python.c

@@ -1556,6 +1556,12 @@ do_pyeval (char_u *str, typval_T *rettv)
 	    rettv->v_type = VAR_NUMBER;
 	    rettv->vval.v_number = 0;
 	    break;
+	case VAR_NUMBER:
+	case VAR_STRING:
+	case VAR_FLOAT:
+	case VAR_JOB:
+	case VAR_SPECIAL:
+	    break;
     }
 }