-- --
-- S p e c --
-- --
--- $Revision: 1.3 $
--- --
--- Copyright (C) 1999-2000 Free Software Foundation, Inc. --
+-- Copyright (C) 1999-2009, 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- --
--- ware Foundation; either version 2, or (at your option) any later ver- --
+-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNAT; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- Public License distributed with GNAT; see file COPYING3. If not, go to --
+-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
--- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
+-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- about uses of uninitialized variables and unused with's. It also has
-- some unrelated routines related to the generation of warnings.
+with Alloc; use Alloc;
+with Table;
with Types; use Types;
package Sem_Warn is
+ ------------------------
+ -- Warnings Off Table --
+ ------------------------
+
+ type Warnings_Off_Entry is record
+ N : Node_Id;
+ -- A pragma Warnings (Off, ent) node
+
+ E : Entity_Id;
+ -- The entity involved
+ end record;
+
+ -- An entry is made in the following table for any valid Pragma Warnings
+ -- (Off, entity) encountered while Opt.Warn_On_Warnings_Off is True. It
+ -- is used to generate warnings on any of these pragmas that turn out not
+ -- to be needed, or that could be replaced by Unmodified/Unreferenced.
+
+ package Warnings_Off_Pragmas is new Table.Table (
+ Table_Component_Type => Warnings_Off_Entry,
+ Table_Index_Type => Int,
+ Table_Low_Bound => 0,
+ Table_Initial => Alloc.Warnings_Off_Pragmas_Initial,
+ Table_Increment => Alloc.Warnings_Off_Pragmas_Increment,
+ Table_Name => "Name_Warnings_Off_Pragmas");
+
+ --------------------
+ -- Initialization --
+ --------------------
+
+ procedure Initialize;
+ -- Initialize this package for new compilation
+
+ function Set_Warning_Switch (C : Character) return Boolean;
+ -- This function sets the warning switch or switches corresponding to the
+ -- given character. It is used to process a -gnatw switch on the command
+ -- line, or a character in a string literal in pragma Warnings. Returns
+ -- True for valid warning character C, False for invalid character.
+
+ function Set_Dot_Warning_Switch (C : Character) return Boolean;
+ -- This function sets the warning switch or switches corresponding to the
+ -- given character preceded by a dot. Used to process a -gnatw. switch on
+ -- the command line or .C in a string literal in pragma Warnings. Returns
+ -- True for valid warning character C, False for invalid character.
+
+ procedure Set_GNAT_Mode_Warnings;
+ -- This is called in -gnatg mode to set the warnings for gnat mode. It is
+ -- also used to set the proper warning statuses for -gnatw.g.
+
------------------------------------------
-- Routines to Handle Unused References --
------------------------------------------
-- using the flags set by the initial call where appropriate to specialize
-- the text of the warning messages.
- ----------------------------------------
- -- Routines to Deal with Conditionals --
- ----------------------------------------
-
- -- These routines provide the necessary interfacing information to
- -- correctly handle references in conditional structures (if/then/end-if,
- -- or case/when/end-case). The issue here is that if a variable is only
- -- set in some but not all branches of a conditional, then it is not
- -- considered as being set by the conditional as a whole.
-
- procedure Start_Unit;
- -- Mark start of new unit to be analyzed, deals with fact that a call to
- -- Rtsfind may cause new unit to be analyzed in middle of conditional.
-
- procedure End_Unit;
- -- Mark end of unit corresponding to previous call to Start_Unit
-
- procedure Start_Conditional (If_Stmt : Boolean);
- -- Mark start of a new conditional structure (an if-elsif-else-endif
- -- or a case-when-end-case structure). If_Stmt is True for the IF
- -- statement case, and False for the CASE statement case.
-
- procedure Start_Branch (Loc : Source_Ptr);
- -- Start processing of one branch of conditional previously marked by
- -- a call to Start_Conditional (i.e. start of then/elsif/else statements
- -- or set of statements after a when condition). The Loc value is the
- -- source pointer to be used in warning messages concerning variables
- -- not properly initialized in this branch. A branch is terminated by
- -- either another Start_Branch or End_Conditional call.
-
- procedure End_Conditional;
- -- Terminate conditional started by previous Start_Conditional statement.
-
---------------------
-- Output Routines --
---------------------
+ procedure Output_Non_Modified_In_Out_Warnings;
+ -- Warnings about IN OUT parameters that could be IN are collected till
+ -- the end of the compilation process (see body of this routine for a
+ -- discussion of why this is done). This procedure outputs the warnings.
+ -- Note: this should be called before Output_Unreferenced_Messages, since
+ -- if we have an IN OUT warning, that's the one we want to see!
+
+ procedure Output_Obsolescent_Entity_Warnings (N : Node_Id; E : Entity_Id);
+ -- N is a reference to obsolescent entity E, for which appropriate warning
+ -- messages are to be generated (caller has already checked that warnings
+ -- are active and appropriate for this entity).
+
procedure Output_Unreferenced_Messages;
-- Warnings about unreferenced entities are collected till the end of
-- the compilation process (see Check_Unset_Reference for further
-- details). This procedure outputs waiting warnings, if any.
+ procedure Output_Unused_Warnings_Off_Warnings;
+ -- Warnings about pragma Warnings (Off, ent) statements that are unused,
+ -- or could be replaced by Unmodified/Unreferenced pragmas, are collected
+ -- till the end of the compilation process. This procedure outputs waiting
+ -- warnings if any.
+
----------------------------
-- Other Warning Routines --
----------------------------
+ procedure Check_Code_Statement (N : Node_Id);
+ -- Perform warning checks on a code statement node
+
+ procedure Check_Infinite_Loop_Warning (Loop_Statement : Node_Id);
+ -- N is the node for a loop statement. This procedure checks if a warning
+ -- should be given for a possible infinite loop, and if so issues it.
+
+ procedure Check_Low_Bound_Tested (Expr : Node_Id);
+ -- Expr is the node for a comparison operation. This procedure checks if
+ -- the comparison is a source comparison of P'First with some other value
+ -- and if so, sets the Low_Bound_Tested flag on entity P to suppress
+ -- warnings about improper low bound assumptions (we assume that if the
+ -- code has a test that explicitly checks P'First, then it is not operating
+ -- in blind assumption mode).
+
procedure Warn_On_Known_Condition (C : Node_Id);
- -- C is a node for a boolean expression resluting from a relational
+ -- C is a node for a boolean expression resulting from a relational
-- or membership operation. If the expression has a compile time known
-- value, then a warning is output if all the following conditions hold:
--
-- If all these conditions are met, the warning is issued noting that
-- the result of the test is always false or always true as appropriate.
+ function Warn_On_Modified_As_Out_Parameter (E : Entity_Id) return Boolean;
+ -- Returns True if we should activate warnings for entity E being modified
+ -- as an out parameter. True if either Warn_On_Modified_Unread is set for
+ -- an only OUT parameter, or if Warn_On_All_Unread_Out_Parameters is set.
+
+ procedure Warn_On_Suspicious_Index (Name : Entity_Id; X : Node_Id);
+ -- This is called after resolving an indexed component or a slice. Name
+ -- is the entity for the name of the indexed array, and X is the subscript
+ -- for the indexed component case, or one of the bounds in the slice case.
+ -- If Name is an unconstrained parameter of a standard string type, and
+ -- the index is of the form of a literal or Name'Length [- literal], then
+ -- a warning is generated that the subscripting operation is possibly
+ -- incorrectly assuming a lower bound of 1.
+
+ procedure Warn_On_Unassigned_Out_Parameter
+ (Return_Node : Node_Id;
+ Scope_Id : Entity_Id);
+ -- Called when processing a return statement given by Return_Node. Scope_Id
+ -- is the Entity_Id for the procedure in which the return statement lives.
+ -- A check is made for the case of a procedure with out parameters that
+ -- have not yet been assigned, and appropriate warnings are given.
+
+ procedure Warn_On_Useless_Assignment
+ (Ent : Entity_Id;
+ N : Node_Id := Empty);
+ -- Called to check if we have a case of a useless assignment to the given
+ -- entity Ent, as indicated by a non-empty Last_Assignment field. This call
+ -- should only be made if at least one of the flags Warn_On_Modified_Unread
+ -- or Warn_On_All_Unread_Out_Parameters is True, and if Ent is in the
+ -- extended main source unit. N is Empty for the end of block call
+ -- (warning message says value unreferenced), or the it is the node for
+ -- an overwriting assignment (warning message points to this assignment).
+
+ procedure Warn_On_Useless_Assignments (E : Entity_Id);
+ pragma Inline (Warn_On_Useless_Assignments);
+ -- Called at the end of a block or subprogram. Scans the entities of the
+ -- block or subprogram to see if there are any variables for which useless
+ -- assignments were made (assignments whose values were never read).
+
end Sem_Warn;
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