No_Tagged_Type_Registration (GNAT Reference Manual)

#### 5.1.62 No_Tagged_Type_Registration ¶

[GNAT] If this restriction is active, then class-wide streaming attributes are not supported. In addition, the subprograms in Ada.Tags are not supported. If this restriction is active, the generated code is simplified by omitting the otherwise-required global registration of tagged types when they are declared. This restriction may be necessary in order to also apply the No_Elaboration_Code restriction.