gnat_rm.texi: First set of documentation additions for predefined RM units.
2014-02-25 Robert Dewar <dewar@adacore.com> * gnat_rm.texi: First set of documentation additions for predefined RM units. * checks.adb: Minor reformatting. * sem_elab.adb (Check_Task_Activation): Minor fix to error message. * sem_util.adb: Minor reformatting. From-SVN: r208141
This commit is contained in:
Robert Dewar
Arnaud Charlet
parent
592574f5b3
commit
9972d439b8
@ -1,3 +1,12 @@
|
||||
2014-02-25 Robert Dewar <dewar@adacore.com>
|
||||
|
||||
* gnat_rm.texi: First set of documentation additions for
|
||||
predefined RM units.
|
||||
* checks.adb: Minor reformatting.
|
||||
* sem_elab.adb (Check_Task_Activation): Minor fix to error
|
||||
message.
|
||||
* sem_util.adb: Minor reformatting.
|
||||
|
||||
2014-02-25 Arnaud Charlet <charlet@adacore.com>
|
||||
|
||||
* usage.adb (Usage): Add help on -gnateC.
|
||||
|
||||
@ -1516,8 +1516,8 @@ package body Checks is
|
||||
|
||||
if Nkind (Original_Node (N)) /= N_Allocator
|
||||
and then (No (Lhs)
|
||||
or else not Is_Entity_Name (Lhs)
|
||||
or else No (Param_Entity (Lhs)))
|
||||
or else not Is_Entity_Name (Lhs)
|
||||
or else No (Param_Entity (Lhs)))
|
||||
then
|
||||
if (Etype (N) = Typ
|
||||
or else (Do_Access and then Designated_Type (Typ) = S_Typ))
|
||||
@ -1767,7 +1767,6 @@ package body Checks is
|
||||
if Do_Overflow_Check (N)
|
||||
and then not Overflow_Checks_Suppressed (Etype (N))
|
||||
then
|
||||
|
||||
-- Test for extremely annoying case of xxx'First divided by -1
|
||||
-- for division of signed integer types (only overflow case).
|
||||
|
||||
|
||||
@ -13751,6 +13751,7 @@ source file location.
|
||||
* Pragma Pack for Arrays::
|
||||
* Pragma Pack for Records::
|
||||
* Record Representation Clauses::
|
||||
* Handling of Records with Holes::
|
||||
* Enumeration Clauses::
|
||||
* Address Clauses::
|
||||
* Effect of Convention on Representation::
|
||||
@ -15092,6 +15093,83 @@ For non-primitive types, including packed arrays with a size greater than
|
||||
type, in particular, always starting on a byte boundary, and the length
|
||||
must be a multiple of the storage unit.
|
||||
|
||||
@node Handling of Records with Holes
|
||||
@section Handling of Records with Holes
|
||||
@cindex Handling of Records with Holes
|
||||
|
||||
As a result of alignment considerations, records may contain "holes"
|
||||
or gaps
|
||||
which do not correspond to the data bits of any of the components.
|
||||
Record representation clauses can also result in holes in records.
|
||||
|
||||
GNAT does not attempt to clear these holes, so in record objects,
|
||||
they should be considered to hold undefined rubbish. The generated
|
||||
equality routine just tests components so does not access these
|
||||
undefined bits, and assignment and copy operations may or may not
|
||||
preserve the contents of these holes (for assignments, the holes
|
||||
in the target will in practice contain either the bits that are
|
||||
present in the holes in the source, or the bits that were present
|
||||
in the target before the assignment).
|
||||
|
||||
If it is necessary to ensure that holes in records have all zero
|
||||
bits, then record objects for which this initialization is desired
|
||||
should be explicitly set to all zero values using Unchecked_Conversion
|
||||
or address overlays. For example
|
||||
|
||||
@smallexample @c ada
|
||||
type HRec is record
|
||||
C : Character;
|
||||
I : Integer;
|
||||
end record;
|
||||
@end smallexample
|
||||
|
||||
@noindent
|
||||
On typical machines, integers need to be aligned on a four-byte
|
||||
boundary, resulting in three bytes of undefined rubbish following
|
||||
the 8-bit field for C. To ensure that the hole in a variable of
|
||||
type HRec is set to all zero bits,
|
||||
you could for example do:
|
||||
|
||||
@smallexample @c ada
|
||||
type Base is record
|
||||
Dummy1, Dummy2 : Integer := 0;
|
||||
end record;
|
||||
|
||||
BaseVar : Base;
|
||||
RealVar : Hrec;
|
||||
for RealVar'Address use BaseVar'Address;
|
||||
@end smallexample
|
||||
|
||||
@noindent
|
||||
Now the 8-bytes of the value of RealVar start out containing all zero
|
||||
bits. A safer approach is to just define dummy fields, avoiding the
|
||||
holes, as in:
|
||||
|
||||
@smallexample @c ada
|
||||
type HRec is record
|
||||
C : Character;
|
||||
Dummy1 : Short_Short_Integer := 0;
|
||||
Dummy2 : Short_Short_Integer := 0;
|
||||
Dummy3 : Short_Short_Integer := 0;
|
||||
I : Integer;
|
||||
end record;
|
||||
@end smallexample
|
||||
|
||||
@noindent
|
||||
And to make absolutely sure that the intent of this is followed, you
|
||||
can use representation clauses:
|
||||
|
||||
@smallexample @c ada
|
||||
for Hrec use record
|
||||
C at 0 range 0 .. 7;
|
||||
Dummy1 at 1 range 0 .. 7;
|
||||
Dummy2 at 2 range 0 .. 7;
|
||||
Dummy3 at 3 range 0 .. 7;
|
||||
I at 4 range 0 .. 31;
|
||||
end record;
|
||||
for Hrec'Size use 64;
|
||||
@end smallexample
|
||||
|
||||
@node Enumeration Clauses
|
||||
@section Enumeration Clauses
|
||||
|
||||
@ -15619,7 +15697,11 @@ together with a brief description of the functionality that is provided.
|
||||
|
||||
For completeness, references are included to other predefined library
|
||||
routines defined in other sections of the Ada Reference Manual (these are
|
||||
cross-indexed from Annex A).
|
||||
cross-indexed from Annex A). For further details see the relevant
|
||||
package declarations in the run-time library. In particular, a few units
|
||||
are not implemented, as marked by the presence of pragma Unimplemented_Unit,
|
||||
and in this case the package declaration contains comments explaining why
|
||||
the unit is not implemented.
|
||||
|
||||
@table @code
|
||||
@item Ada (A.2)
|
||||
@ -15627,13 +15709,35 @@ This is a parent package for all the standard library packages. It is
|
||||
usually included implicitly in your program, and itself contains no
|
||||
useful data or routines.
|
||||
|
||||
@item Ada.Assertions (11.4.2)
|
||||
@code{Assertions} provides the @code{Assert} subprograms, and also
|
||||
the declaration of the @code{Assertion_Error} exception.
|
||||
|
||||
@item Ada.Asynchronous_Task_Control (D.11)
|
||||
@code{Asynchronous_Task_Control} provides low level facilities for task
|
||||
synchronization. It is typically not implemented. See package spec for details.
|
||||
|
||||
@item Ada.Calendar (9.6)
|
||||
@code{Calendar} provides time of day access, and routines for
|
||||
manipulating times and durations.
|
||||
|
||||
@item Ada.Calendar.Arithmetic (9.6.1)
|
||||
This package provides additional arithmetic
|
||||
operations for @code{Calendar}.
|
||||
|
||||
@item Ada.Calendar.Formatting (9.6.1)
|
||||
This package provides formatting operations for @code{Calendar}.
|
||||
|
||||
@item Ada.Calendar.Time_Zones (9.6.1)
|
||||
This package provides additional @code{Calendar} facilities
|
||||
for handling time zones.
|
||||
|
||||
@item Ada.Characters (A.3.1)
|
||||
This is a dummy parent package that contains no useful entities
|
||||
|
||||
@item Ada.Characters.Conversions (A.3.2)
|
||||
This package provides character conversion functions.
|
||||
|
||||
@item Ada.Characters.Handling (A.3.2)
|
||||
This package provides some basic character handling capabilities,
|
||||
including classification functions for classes of characters (e.g.@: test
|
||||
@ -15654,6 +15758,71 @@ of the current program (analogous to the use of @code{argc} and @code{argv}
|
||||
in C), and also allows the exit status for the program to be set in a
|
||||
system-independent manner.
|
||||
|
||||
@item Ada.Complex_Text_IO (G.1.3)
|
||||
This package provides text input and output of complex numbers.
|
||||
|
||||
@item Ada.Containers (A.18.1)
|
||||
A top level package providing a few basic definitions used by all the
|
||||
following specific child packages that provide specific kinds of
|
||||
containers.
|
||||
|
||||
@item Ada.Containers.Bounded_Priority_Queues (A.18.31)
|
||||
|
||||
@item Ada.Containers.Bounded_Synchronized_Queues (A.18.29)
|
||||
|
||||
@item Ada.Containers.Doubly_Linked_Lists (A.18.3)
|
||||
|
||||
@item Ada.Containers.Generic_Array_Sort (A.18.26)
|
||||
|
||||
@item Ada.Containers.Generic_Constrained_Array_Sort (A.18.26)
|
||||
|
||||
@item Ada.Containers.Generic_Sort (A.18.26)
|
||||
|
||||
@item Ada.Containers.Hashed_Maps (A.18.5)
|
||||
|
||||
@item Ada.Containers.Hashed_Sets (A.18.8)
|
||||
|
||||
@item Ada.Containers.Indefinite_Doubly_Linked_Lists (A.18.12)
|
||||
|
||||
@item Ada.Containers.Indefinite_Hashed_Maps (A.18.13)
|
||||
|
||||
@item Ada.Containers.Indefinite_Hashed_Sets (A.18.15)
|
||||
|
||||
@item Ada.Containers.Indefinite_Holders (A.18.18)
|
||||
|
||||
@item Ada.Containers.Indefinite_Multiway_Trees (A.18.17)
|
||||
|
||||
@item Ada.Containers.Indefinite_Ordered_Maps (A.18.14)
|
||||
|
||||
@item Ada.Containers.Indefinite_Ordered_Sets (A.18.16)
|
||||
|
||||
@item Ada.Containers.Indefinite_Vectors (A.18.11)
|
||||
|
||||
@item Ada.Containers.Multiway_Trees (A.18.10)
|
||||
|
||||
@item Ada.Containers.Ordered_Maps (A.18.6)
|
||||
|
||||
@item Ada.Containers.Ordered_Sets (A.18.9)
|
||||
|
||||
@item Ada.Containers.Synchronized_Queue_Interfaces (A.18.27)
|
||||
|
||||
@item Ada.Containers.Unbounded_Priority_Queues (A.18.30)
|
||||
|
||||
@item Ada.Containers.Unbounded_Synchronized_Queues (A.18.28)
|
||||
|
||||
@item Ada.Containers.Vectors (A.18.2)
|
||||
|
||||
@item Ada.Directories (A.16)
|
||||
This package provides operations on directories.
|
||||
|
||||
@item Ada.Directories.Hierarchical_File_Names (A.16.1)
|
||||
This package provides additional directory operations handling
|
||||
hiearchical file names.
|
||||
|
||||
@item Ada.Directories.Information (A.16)
|
||||
This is an implementation defined package for additional directory
|
||||
operations, which is not implemented in GNAT.
|
||||
|
||||
@item Ada.Decimal (F.2)
|
||||
This package provides constants describing the range of decimal numbers
|
||||
implemented, and also a decimal divide routine (analogous to the COBOL
|
||||
@ -15664,19 +15833,61 @@ This package provides input-output using a model of a set of records of
|
||||
fixed-length, containing an arbitrary definite Ada type, indexed by an
|
||||
integer record number.
|
||||
|
||||
@item Ada.Dispatching (D.2.1)
|
||||
A parent package containing definitions for task dispatching operations.
|
||||
|
||||
@item Ada.Dispatching.EDF (D.2.6)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Dispatching.Non_Preemptive (D.2.4)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Dispatching.Round_Robin (D.2.5)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Dynamic_Priorities (D.5)
|
||||
This package allows the priorities of a task to be adjusted dynamically
|
||||
as the task is running.
|
||||
|
||||
@item Ada.Environment_Variables (A.17)
|
||||
This package provides facilities for accessing environment variables.
|
||||
|
||||
@item Ada.Exceptions (11.4.1)
|
||||
This package provides additional information on exceptions, and also
|
||||
contains facilities for treating exceptions as data objects, and raising
|
||||
exceptions with associated messages.
|
||||
|
||||
@item Ada.Execution_Time (D.14)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Execution_Time.Group_Budgets (D.14.2)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Execution_Time.Timers (D.14.1)'
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Finalization (7.6)
|
||||
This package contains the declarations and subprograms to support the
|
||||
use of controlled types, providing for automatic initialization and
|
||||
finalization (analogous to the constructors and destructors of C++)
|
||||
finalization (analogous to the constructors and destructors of C++).
|
||||
|
||||
@item Ada.Float_Text_IO (A.10.9)
|
||||
A library level instantiation of Text_IO.Float_IO for type Float.
|
||||
|
||||
@item Ada.Float_Wide_Text_IO (A.10.9)
|
||||
A library level instantiation of Wide_Text_IO.Float_IO for type Float.
|
||||
|
||||
@item Ada.Float_Wide_Wide_Text_IO (A.10.9)
|
||||
A library level instantiation of Wide_Wide_Text_IO.Float_IO for type Float.
|
||||
|
||||
@item Ada.Integer_Text_IO (A.10.9)
|
||||
A library level instantiation of Text_IO.Integer_IO for type Integer.
|
||||
|
||||
@item Ada.Integer_Wide_Text_IO (A.10.9)
|
||||
A library level instantiation of Wide_Text_IO.Integer_IO for type Integer.
|
||||
|
||||
@item Ada.Integer_Wide_Wide_Text_IO (A.10.9)
|
||||
A library level instantiation of Wide_Wide_Text_IO.Integer_IO for type Integer.
|
||||
|
||||
@item Ada.Interrupts (C.3.2)
|
||||
This package provides facilities for interfacing to interrupts, which
|
||||
@ -15691,12 +15902,22 @@ or condition names) that can be handled by GNAT@.
|
||||
This package defines the set of exceptions that can be raised by use of
|
||||
the standard IO packages.
|
||||
|
||||
@item Ada.Iterator_Interfaces (5.5.1)
|
||||
This package provides a generic interface to generalized iterators.
|
||||
|
||||
@item Ada.Locales (A.19)
|
||||
This package provides declarations providing information (Language
|
||||
and Country) about the current locale.
|
||||
|
||||
@item Ada.Numerics
|
||||
This package contains some standard constants and exceptions used
|
||||
throughout the numerics packages. Note that the constants pi and e are
|
||||
defined here, and it is better to use these definitions than rolling
|
||||
your own.
|
||||
|
||||
@item Ada.Numerics.Complex_Arrays (G.3.2)
|
||||
Provides operations on arrays of complex numbers.
|
||||
|
||||
@item Ada.Numerics.Complex_Elementary_Functions
|
||||
Provides the implementation of standard elementary functions (such as
|
||||
log and trigonometric functions) operating on complex numbers using the
|
||||
@ -15762,6 +15983,12 @@ The following predefined instantiations of this package exist
|
||||
@code{Ada.Numerics.Long_Elementary_Functions}
|
||||
@end table
|
||||
|
||||
@item Ada.Numerics.Generic_Real_Arrays (G.3.1)
|
||||
Generic operations on arrays of reals
|
||||
|
||||
@item Ada.Numerics.Real_Arrays (G.3.1)
|
||||
Preinstantiation of Ada.Numerics.Generic_Real_Arrays (Float).
|
||||
|
||||
@item Ada.Real_Time (D.8)
|
||||
This package provides facilities similar to those of @code{Calendar}, but
|
||||
operating with a finer clock suitable for real time control. Note that
|
||||
@ -15770,6 +15997,9 @@ guarantees this behavior, but of course if the external clock on which
|
||||
the GNAT runtime depends is deliberately reset by some external event,
|
||||
then such a backward jump may occur.
|
||||
|
||||
@item Ada.Real_Time.Timing_Events (D.15)
|
||||
Not implemented in GNAT.
|
||||
|
||||
@item Ada.Sequential_IO (A.8.1)
|
||||
This package provides input-output facilities for sequential files,
|
||||
which can contain a sequence of values of a single type, which can be
|
||||
@ -15802,6 +16032,9 @@ strings. The bounded model requires a maximum length. It is thus
|
||||
somewhat more limited than the unbounded model, but avoids the use of
|
||||
dynamic allocation or finalization.
|
||||
|
||||
@item Ada.Strings.Bounded.Equal_Case_Insensitive (A.4.10)
|
||||
Provides case-insensitive comparisons of bounded strings
|
||||
|
||||
@item Ada.Strings.Fixed (A.4.3)
|
||||
This package provides facilities for handling fixed length strings.
|
||||
|
||||
|
||||
@ -2557,7 +2557,7 @@ package body Sem_Elab is
|
||||
Error_Msg_Node_2 := Task_Scope;
|
||||
Error_Msg_NE
|
||||
("info: activation of an instance of task type&" &
|
||||
" requires pragma Elaborate_All on &?l?", N, Ent);
|
||||
" requires pragma Elaborate_All on &?", N, Ent);
|
||||
end if;
|
||||
|
||||
Activate_Elaborate_All_Desirable (N, Task_Scope);
|
||||
|
||||
@ -11989,8 +11989,6 @@ package body Sem_Util is
|
||||
Last_Assignment_Only : Boolean := False)
|
||||
is
|
||||
begin
|
||||
-- ??? do we have to worry about clearing cached checks?
|
||||
|
||||
if Is_Assignable (Ent) then
|
||||
Set_Last_Assignment (Ent, Empty);
|
||||
end if;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user