procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

a-tasatt.adb, [...] (Fast_Path): Rewritten to avoid reading potentially uninitialized memory.

Browse source 
2016-04-21  Arnaud Charlet  <charlet@adacore.com>

	* a-tasatt.adb, a-tasatt.ads (Fast_Path): Rewritten to avoid reading
	potentially uninitialized memory.
	* sem_ch3.adb: Minor style fix in comment.

From-SVN: r235329
This commit is contained in:
Arnaud Charlet 2016-04-21 10:21:56 +00:00 • committed by Arnaud Charlet
parent c25f170d2d
commit 150346bd8d
4 changed files with 23 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
gcc/ada/ChangeLog
View file

@ -1,3 +1,9 @@
2016-04-21 Arnaud Charlet <charlet@adacore.com>
* a-tasatt.adb, a-tasatt.ads (Fast_Path): Rewritten to avoid reading
potentially uninitialized memory.
* sem_ch3.adb: Minor style fix in comment.
2016-04-21 Arnaud Charlet <charlet@adacore.com>
* gnat_rm.texi, gnat_ugn.texi,

14
gcc/ada/a-tasatt.adb
View file

@ -6,7 +6,7 @@
-- --
-- B o d y --
-- --
-- Copyright (C) 2014, Free Software Foundation, Inc. --
-- Copyright (C) 2014-2016, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
@ -93,6 +93,11 @@ package body Ada.Task_Attributes is
function To_Attribute is new
Ada.Unchecked_Conversion (Atomic_Address, Attribute);
function To_Address is new
Ada.Unchecked_Conversion (Attribute, System.Address);
function To_Int is new
Ada.Unchecked_Conversion (Attribute, Integer);
pragma Warnings (On);
function To_Address is new
@ -114,9 +119,12 @@ package body Ada.Task_Attributes is
Ada.Unchecked_Deallocation (Real_Attribute, Real_Attribute_Access);
Fast_Path : constant Boolean :=
Attribute'Size <= Atomic_Address'Size
(Attribute'Size = Integer'Size
and then Attribute'Alignment <= Atomic_Address'Alignment
and then To_Address (Initial_Value) = 0;
and then To_Int (Initial_Value) = 0)
or else (Attribute'Size = System.Address'Size
and then Attribute'Alignment <= Atomic_Address'Alignment
and then To_Address (Initial_Value) = System.Null_Address);
-- If the attribute fits in an Atomic_Address (both size and alignment)
-- and Initial_Value is 0 (or null), then we will map the attribute
-- directly into ATCB.Attributes (Index), otherwise we will create

7
gcc/ada/a-tasatt.ads
View file

@ -6,7 +6,7 @@
-- --
-- S p e c --
-- --
-- Copyright (C) 2014, Free Software Foundation, Inc. --
-- Copyright (C) 2014-2016, Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
@ -42,8 +42,9 @@ generic
package Ada.Task_Attributes is
-- Note that this package will use an efficient implementation with no
-- locks and no extra dynamic memory allocation if Attribute can fit in a
-- System.Address type, and Initial_Value is 0 (null for an access type).
-- locks and no extra dynamic memory allocation if Attribute is the size
-- of either Integer or System.Address, and Initial_Value is 0 (null for
-- an access type).
-- Other types and initial values are supported, but will require
-- the use of locking and a level of indirection (meaning extra dynamic

4
gcc/ada/sem_ch3.adb
View file

@ -3423,7 +3423,7 @@ package body Sem_Ch3 is
if Error_Posted (N) then
-- Type mismatch or illegal redeclaration, Do not analyze
-- Type mismatch or illegal redeclaration; do not analyze
-- expression to avoid cascaded errors.
T := Find_Type_Of_Object (Object_Definition (N), N);
@ -3460,7 +3460,7 @@ package body Sem_Ch3 is
end if;
-- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
-- out some static checks
-- out some static checks.
if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then