diff options
Diffstat (limited to 'gcc/ada/sem_attr.ads')
| -rw-r--r-- | gcc/ada/sem_attr.ads | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/gcc/ada/sem_attr.ads b/gcc/ada/sem_attr.ads index 71ac668c757..7258593aabf 100644 --- a/gcc/ada/sem_attr.ads +++ b/gcc/ada/sem_attr.ads @@ -554,12 +554,33 @@ package Sem_Attr is ------------------- Attribute_Valid_Scalars => True, - -- Obj'Valid_Scalars applies to objects of scalar types, on which it is - -- equivalent to Obj'Valid, and objects of array and record types, on - -- which it amounts to applying 'Valid to each subcomponent of Obj. It - -- does not apply to prefixes of classwide type, or of a formal generic - -- type that has an unknown discriminant (which could be instantiated - -- with a classwide type). + -- Obj'Valid_Scalars can be applied to any object. The result depends + -- on the type of the object: + -- + -- For a scalar type, the result is the same as obj'Valid + -- + -- For an array object, the result is True if the result of applying + -- Valid_Scalars to every component is True. For an empty array the + -- result is True. + -- + -- For a record object, the result is True if the result of applying + -- Valid_Scalars to every component is True. For class-wide types, + -- only the components of the base type are checked. For variant + -- records, only the components actually present are checked. The + -- discriminants, if any, are also checked. If there are no components + -- or discriminants, the result is True. + -- + -- For any other type that has discriminants, the result is True if + -- the result of applying Valid_Scalars to each discriminant is True. + -- + -- For all other types, the result is always True + -- + -- A warning is given for a trivially True result, when the attribute + -- is applied to an object that is not of scalar, array, or record + -- type, or in the composite case if no scalar subcomponents exist. For + -- a variant record, the warning is given only if none of the variants + -- have scalar subcomponents. In addition, the warning is suppressed + -- for private types, or generic formal types in an instance. ---------------- -- Value_Size -- |