pragma Suppress_Initialization ([Entity =>] subtype_Name);
Here subtype_Name is the name introduced by a type declaration or subtype declaration. This pragma suppresses any implicit or explicit initialization for all variables of the given type or subtype, including initialization resulting from the use of pragmas Normalize_Scalars or Initialize_Scalars.
This is considered a representation item, so it cannot be given after the type is frozen. It applies to all subsequent object declarations, and also any allocator that creates objects of the type.
If the pragma is given for the first subtype, then it is considered to apply to the base type and all its subtypes. If the pragma is given for other than a first subtype, then it applies only to the given subtype. The pragma may not be given after the type is frozen.