------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- W A R N S W --
-- --
-- S p e c --
-- --
-- Copyright (C) 1999-2023, 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 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 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. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This unit contains the routines used to handle setting of warning options
-- in the GNAT compiler.
package Warnsw is
-------------------
-- Warning Flags --
-------------------
-- These flags are activated or deactivated by -gnatw switches and control
-- whether warnings of a given class will be generated or not.
package Warnings_Package is
type Opt_Warnings_Enum is
-- List of all warnings that can be enabled, plus the two null-ish
-- values.
(No_Such_Warning, Special_Case, -- see body
Address_Clause_Overlay_Warnings,
Check_Unreferenced,
Check_Unreferenced_Formals,
Check_Withs,
Constant_Condition_Warnings,
Elab_Info_Messages,
Elab_Warnings,
Implementation_Unit_Warnings,
Ineffective_Inline_Warnings,
List_Body_Required_Info,
List_Inherited_Aspects,
Warning_Doc_Switch,
Warn_On_Ada_2005_Compatibility,
Warn_On_Ada_2012_Compatibility,
Warn_On_Ada_2022_Compatibility,
Warn_On_All_Unread_Out_Parameters,
Warn_On_Anonymous_Allocators,
Warn_On_Assertion_Failure,
Warn_On_Assumed_Low_Bound,
Warn_On_Atomic_Synchronization,
Warn_On_Bad_Fixed_Value,
Warn_On_Biased_Representation,
Warn_On_Component_Order,
Warn_On_Constant,
Warn_On_Deleted_Code,
Warn_On_Dereference,
Warn_On_Elab_Access,
Warn_On_Export_Import,
Warn_On_Hiding,
Warn_On_Ignored_Equality,
Warn_On_Late_Primitives,
Warn_On_Modified_Unread,
Warn_On_No_Value_Assigned,
Warn_On_Non_Local_Exception,
No_Warn_On_Non_Local_Exception,
Warn_On_Object_Renames_Function,
Warn_On_Obsolescent_Feature,
Warn_On_Overlap,
Warn_On_Overridden_Size,
Warn_On_Parameter_Order,
Warn_On_Pedantic_Checks,
Warn_On_Questionable_Layout,
Warn_On_Questionable_Missing_Parens,
Warn_On_Record_Holes,
Warn_On_Redundant_Constructs,
Warn_On_Reverse_Bit_Order,
Warn_On_Size_Alignment,
Warn_On_Standard_Redefinition,
Warn_On_Suspicious_Contract,
Warn_On_Suspicious_Modulus_Value,
Warn_On_Unchecked_Conversion,
Warn_On_Unknown_Compile_Time_Warning,
Warn_On_Unordered_Enumeration_Type,
Warn_On_Unrecognized_Pragma,
Warn_On_Unrepped_Components,
Warn_On_Warnings_Off); -- Opt_Warnings_Enum
subtype Warnings_Enum is Opt_Warnings_Enum
range Opt_Warnings_Enum'Succ (Special_Case) .. Opt_Warnings_Enum'Last;
-- Just the warning switches, without the null-ish values
end Warnings_Package;
use Warnings_Package;
type Warnings_State is array (Warnings_Enum) of Boolean;
pragma Pack (Warnings_State);
-- Without Pack, we can have bootstrapping failures, because the compiler
-- generates calls to System.Boolean_Array_Operations, which is not
-- currently part of the compiler.
Warning_Flags : Warnings_State :=
-- Current state of warnings -- True/False means enabled/disabled.
-- The following initializes the flags to their default values,
-- and warning switches modify them.
(Address_Clause_Overlay_Warnings |
Elab_Warnings |
Implementation_Unit_Warnings |
Warning_Doc_Switch |
Warn_On_Ada_2005_Compatibility |
Warn_On_Ada_2012_Compatibility |
Warn_On_Ada_2022_Compatibility |
Warn_On_Assertion_Failure |
Warn_On_Assumed_Low_Bound |
Warn_On_Biased_Representation |
Warn_On_Export_Import |
Warn_On_No_Value_Assigned |
Warn_On_Questionable_Missing_Parens |
Warn_On_Reverse_Bit_Order |
Warn_On_Size_Alignment |
Warn_On_Suspicious_Contract |
Warn_On_Suspicious_Modulus_Value |
Warn_On_Unchecked_Conversion |
Warn_On_Unknown_Compile_Time_Warning |
Warn_On_Unrecognized_Pragma =>
True,
Check_Unreferenced |
Check_Unreferenced_Formals |
Check_Withs |
Constant_Condition_Warnings |
Elab_Info_Messages |
Ineffective_Inline_Warnings |
List_Body_Required_Info |
List_Inherited_Aspects |
Warn_On_All_Unread_Out_Parameters |
Warn_On_Anonymous_Allocators |
Warn_On_Atomic_Synchronization |
Warn_On_Bad_Fixed_Value |
Warn_On_Component_Order |
Warn_On_Constant |
Warn_On_Deleted_Code |
Warn_On_Dereference |
Warn_On_Elab_Access |
Warn_On_Hiding |
Warn_On_Ignored_Equality |
Warn_On_Late_Primitives |
Warn_On_Modified_Unread |
Warn_On_Non_Local_Exception |
No_Warn_On_Non_Local_Exception |
Warn_On_Object_Renames_Function |
Warn_On_Obsolescent_Feature |
Warn_On_Overlap |
Warn_On_Overridden_Size |
Warn_On_Parameter_Order |
Warn_On_Pedantic_Checks |
Warn_On_Questionable_Layout |
Warn_On_Record_Holes |
Warn_On_Redundant_Constructs |
Warn_On_Standard_Redefinition |
Warn_On_Unordered_Enumeration_Type |
Warn_On_Unrepped_Components |
Warn_On_Warnings_Off =>
False);
package X renames Warnings_Package;
F : Warnings_State renames Warning_Flags;
-- Short-hand names used only locally to this package
-- The following rename all the components of Warning_Flags for convenient
-- access throughout the compiler.
pragma Style_Checks ("M120");
Address_Clause_Overlay_Warnings : Boolean renames F (X.Address_Clause_Overlay_Warnings);
-- Set False to disable address clause warnings. Modified by use of
-- -gnatwo/O.
Check_Unreferenced : Boolean renames F (X.Check_Unreferenced);
-- Set to True to enable checking for unreferenced entities other
-- than formal parameters (for which see Check_Unreferenced_Formals)
-- Modified by use of -gnatwu/U.
Check_Unreferenced_Formals : Boolean renames F (X.Check_Unreferenced_Formals);
-- Set to True to check for unreferenced formals. This is turned on by
-- -gnatwa/wf/wu and turned off by -gnatwA/wF/wU.
Check_Withs : Boolean renames F (X.Check_Withs);
-- Set to True to enable checking for unused withs, and also the case
-- of withing a package and using none of the entities in the package.
-- Modified by use of -gnatwu/U.
Constant_Condition_Warnings : Boolean renames F (X.Constant_Condition_Warnings);
-- Set to True to activate warnings on constant conditions. Modified by
-- use of -gnatwc/C.
Elab_Info_Messages : Boolean renames F (X.Elab_Info_Messages);
-- Set to True to output info messages for static elabmodel (-gnatel)
Elab_Warnings : Boolean renames F (X.Elab_Warnings);
-- Set to True to generate elaboration warnings (-gnatwl). The warnings are
-- enabled by default because they carry the same importance as errors. The
-- compiler cannot emit actual errors because elaboration diagnostics need
-- dataflow analysis, which is not available. This behavior parallels that
-- of the old ABE mechanism.
Implementation_Unit_Warnings : Boolean renames F (X.Implementation_Unit_Warnings);
-- Set True to active warnings for use of implementation internal units.
-- Modified by use of -gnatwi/-gnatwI.
Ineffective_Inline_Warnings : Boolean renames F (X.Ineffective_Inline_Warnings);
-- Set True to activate warnings if front-end inlining (-gnatN) is not able
-- to actually inline a particular call (or all calls). Can be controlled
-- by use of -gnatwp/-gnatwP. Also set True to activate warnings if
-- frontend inlining is not able to inline a subprogram expected to
-- be inlined in GNATprove mode.
List_Body_Required_Info : Boolean renames F (X.List_Body_Required_Info);
-- List info messages about why a package requires a body. Modified by use
-- of -gnatw.y/.Y.
List_Inherited_Aspects : Boolean renames F (X.List_Inherited_Aspects);
-- List inherited invariants, preconditions, and postconditions from
-- Invariant'Class, Pre'Class, and Post'Class aspects. Also list inherited
-- subtype predicates. Modified by use of -gnatw.l/.L.
Warning_Doc_Switch : Boolean renames F (X.Warning_Doc_Switch);
-- If this is set True, then the ??/?*?/?$?/?x?/?.x?/?_x? insertion
-- sequences in error messages generate appropriate tags for the output
-- error messages. If this switch is False, then these sequences are still
-- recognized (for the purposes of implementing the pattern matching in
-- pragmas Warnings (Off,..) and Warning_As_Error(...) but do not result
-- in adding the error message tag. The -gnatw.d switch sets this flag
-- True, -gnatw.D sets this flag False.
Warn_On_Ada_2005_Compatibility : Boolean renames F (X.Warn_On_Ada_2005_Compatibility);
-- Set to True to generate all warnings on Ada 2005 compatibility issues,
-- including warnings on Ada 2005 obsolescent features used in Ada 2005
-- mode. Set by default, modified by use of -gnatwy/Y.
Warn_On_Ada_2012_Compatibility : Boolean renames F (X.Warn_On_Ada_2012_Compatibility);
-- Set to True to generate all warnings on Ada 2012 compatibility issues,
-- including warnings on Ada 2012 obsolescent features used in Ada 2012
-- mode. Modified by use of -gnatwy/Y.
Warn_On_Ada_2022_Compatibility : Boolean renames F (X.Warn_On_Ada_2022_Compatibility);
-- Set to True to generate all warnings on Ada 2022 compatibility issues,
-- including warnings on Ada 2022 obsolescent features used in Ada 2022
-- mode. There is no switch controlling this option.
Warn_On_All_Unread_Out_Parameters : Boolean renames F (X.Warn_On_All_Unread_Out_Parameters);
-- Set to True to generate warnings in all cases where a variable is
-- modified by being passed as to an OUT formal, but the resulting value is
-- never read. The default is that this warning is suppressed. Modified
-- by use of gnatw.o/.O.
Warn_On_Anonymous_Allocators : Boolean renames F (X.Warn_On_Anonymous_Allocators);
-- Warn when allocators for anonymous access types are present, which,
-- although not illegal in Ada, may be confusing to users due to how
-- accessibility checks get generated. Off by default, modified by use
-- of -gnatw_a/_A and set as part of -gnatwa.
Warn_On_Assertion_Failure : Boolean renames F (X.Warn_On_Assertion_Failure);
-- Set to True to activate warnings on assertions that can be determined
-- at compile time will always fail. Modified by use of -gnatw.a/.A.
Warn_On_Assumed_Low_Bound : Boolean renames F (X.Warn_On_Assumed_Low_Bound);
-- Set to True to activate warnings for string parameters that are indexed
-- with literals or S'Length, presumably assuming a lower bound of one.
-- Modified by use of -gnatww/W.
Warn_On_Atomic_Synchronization : Boolean renames F (X.Warn_On_Atomic_Synchronization);
-- Set to True to generate information messages for atomic synchronization.
-- Modified by use of -gnatw.n/.N.
Warn_On_Bad_Fixed_Value : Boolean renames F (X.Warn_On_Bad_Fixed_Value);
-- Set to True to generate warnings for static fixed-point expression
-- values that are not an exact multiple of the small value of the type.
-- Odd by default, modified by use of -gnatwb/B.
Warn_On_Biased_Representation : Boolean renames F (X.Warn_On_Biased_Representation);
-- Set to True to generate warnings for size clauses, component clauses
-- and component_size clauses that force biased representation. Modified
-- by use of -gnatw.b/.B.
Warn_On_Component_Order : Boolean renames F (X.Warn_On_Component_Order);
-- Warn when record component clauses are out of order with respect to the
-- component declarations, or if the memory layout is out of order with
-- respect to component declarations and clauses. Off by default, set by
-- -gnatw_r (but not -gnatwa).
Warn_On_Constant : Boolean renames F (X.Warn_On_Constant);
-- Set to True to generate warnings for variables that could be declared
-- as constants. Modified by use of -gnatwk/K.
Warn_On_Deleted_Code : Boolean renames F (X.Warn_On_Deleted_Code);
-- Set to True to generate warnings for code deleted by the front end
-- for conditional statements whose outcome is known at compile time.
-- Modified by use of -gnatwt/T.
Warn_On_Dereference : Boolean renames F (X.Warn_On_Dereference);
-- Set to True to generate warnings for implicit dereferences for array
-- indexing and record component access. Modified by use of -gnatwd/D.
Warn_On_Elab_Access : Boolean renames F (X.Warn_On_Elab_Access);
-- Set to True to generate warnings for P'Access in the case where
-- subprogram P is in the same package as the P'Access, and the P'Access is
-- evaluated at package elaboration time, and occurs before the body of P
-- has been elaborated. Modified by use of -gnatw.f/.F.
Warn_On_Export_Import : Boolean renames F (X.Warn_On_Export_Import);
-- Set to True to generate warnings for suspicious use of export or
-- import pragmas. Modified by use of -gnatwx/X.
Warn_On_Hiding : Boolean renames F (X.Warn_On_Hiding);
-- Set to True to generate warnings if a declared entity hides another
-- entity. The default is that this warning is suppressed. Modified by
-- use of -gnatwh/H.
Warn_On_Ignored_Equality : Boolean renames F (X.Warn_On_Ignored_Equality);
-- Warn when a user-defined "=" function does not compose (i.e. is ignored
-- for a predefined "=" for a composite type containing a component of
-- whose type has the user-defined "=" as primitive). Off by default, and
-- set by -gnatw_q (but not -gnatwa).
Warn_On_Late_Primitives : Boolean renames F (X.Warn_On_Late_Primitives);
-- Warn when tagged type public primitives are defined after its private
-- extensions.
Warn_On_Modified_Unread : Boolean renames F (X.Warn_On_Modified_Unread);
-- Set to True to generate warnings if a variable is assigned but is never
-- read. Also controls warnings for similar cases involving out parameters,
-- but only if there is only one out parameter for the procedure involved.
-- The default is that this warning is suppressed, modified by use of
-- -gnatwm/M.
Warn_On_No_Value_Assigned : Boolean renames F (X.Warn_On_No_Value_Assigned);
-- Set to True to generate warnings if no value is ever assigned to a
-- variable that is at least partially uninitialized. Set to false to
-- suppress such warnings. The default is that such warnings are enabled.
-- Modified by use of -gnatwv/V.
Warn_On_Non_Local_Exception : Boolean renames F (X.Warn_On_Non_Local_Exception);
-- Set to True to generate warnings for non-local exception raises and also
-- handlers that can never handle a local raise. This warning is only ever
-- generated if pragma Restrictions (No_Exception_Propagation) is set. The
-- default is not to generate the warnings except that if the source has
-- at least one exception handler, and this restriction is set, and the
-- warning was not explicitly turned off, then it is turned on by default.
-- Modified by use of -gnatw.x/.X.
No_Warn_On_Non_Local_Exception : Boolean renames F (X.No_Warn_On_Non_Local_Exception);
-- This is set to True if the above warning is explicitly suppressed. We
-- use this to avoid turning it on by default when No_Exception_Propagation
-- restriction is set and an exception handler is present.
Warn_On_Object_Renames_Function : Boolean renames F (X.Warn_On_Object_Renames_Function);
-- Set to True to generate warnings when a function result is renamed as
-- an object. The default is that this warning is disabled. Modified by
-- use of -gnatw.r/.R.
Warn_On_Obsolescent_Feature : Boolean renames F (X.Warn_On_Obsolescent_Feature);
-- Set to True to generate warnings on use of any feature in Annex or if a
-- subprogram is called for which a pragma Obsolescent applies. Modified
-- by use of -gnatwj/J.
Warn_On_Overlap : Boolean renames F (X.Warn_On_Overlap);
-- Set to True to generate warnings when a writable actual overlaps with
-- another actual in a subprogram call. This applies only in modes before
-- Ada 2012. Starting with Ada 2012, such overlaps are illegal.
-- Modified by use of -gnatw.i/.I.
Warn_On_Overridden_Size : Boolean renames F (X.Warn_On_Overridden_Size);
-- Warn when explicit record component clause or array component_size
-- clause specifies a size that overrides a size for the type which was
-- set with an explicit size clause. Off by default, modified by use of
-- -gnatw.s/.S (but not -gnatwa).
Warn_On_Parameter_Order : Boolean renames F (X.Warn_On_Parameter_Order);
-- Set to True to generate warnings for cases where the argument list for
-- a call is a sequence of identifiers that match the formal identifiers,
-- but are in the wrong order.
Warn_On_Pedantic_Checks : Boolean renames F (X.Warn_On_Pedantic_Checks);
-- Warn for violation of miscellaneous pedantic rules (such as when the
-- subtype of a formal parameter given in a subprogram body's specification
-- comes from a different subtype declaration that the subtype of the
-- formal in the subprogram declaration). Off by default, and set by
-- -gnatw_p (but not -gnatwa).
Warn_On_Questionable_Layout : Boolean renames F (X.Warn_On_Questionable_Layout);
-- Warn when default layout of a record type is questionable for run-time
-- efficiency reasons and would be improved by reordering the components.
-- Off by default, modified by use of -gnatw.q/.Q (but not -gnatwa).
function Get_Warn_On_Questionable_Layout return Boolean is
(Warn_On_Questionable_Layout);
-- WARNING: There is a matching C declaration of this function in fe.h
Warn_On_Questionable_Missing_Parens : Boolean renames F (X.Warn_On_Questionable_Missing_Parens);
-- Set to True to generate warnings for cases where parentheses are missing
-- and the usage is questionable, because the intent is unclear. On by
-- default, modified by use of -gnatwq/Q.
Warn_On_Record_Holes : Boolean renames F (X.Warn_On_Record_Holes);
-- Warn when explicit record component clauses leave uncovered holes (gaps)
-- in a record layout. Off by default, set by -gnatw.h (but not -gnatwa).
Warn_On_Redundant_Constructs : Boolean renames F (X.Warn_On_Redundant_Constructs);
-- Set to True to generate warnings for redundant constructs (e.g. useless
-- assignments/conversions). The default is that this warning is disabled.
-- Modified by use of -gnatwr/R.
Warn_On_Reverse_Bit_Order : Boolean renames F (X.Warn_On_Reverse_Bit_Order);
-- Set to True to generate warning (informational) messages for component
-- clauses that are affected by non-standard bit-order. The default is
-- that this warning is enabled. Modified by -gnatw.v/.V.
Warn_On_Size_Alignment : Boolean renames F (X.Warn_On_Size_Alignment);
-- Warn when explicit Size and Alignment clauses are given for a type, and
-- the size is not a multiple of the alignment. Off by default, modified
-- by use of -gnatw.z/.Z and set as part of -gnatwa.
Warn_On_Standard_Redefinition : Boolean renames F (X.Warn_On_Standard_Redefinition);
-- Warn when a program defines an identifier that matches a name in
-- Standard. Off by default, modified by use of -gnatw.k/.K (but not
-- by -gnatwa).
Warn_On_Suspicious_Contract : Boolean renames F (X.Warn_On_Suspicious_Contract);
-- Set to True to generate warnings for suspicious contracts expressed as
-- pragmas or aspects precondition and postcondition, as well as other
-- suspicious cases of expressions typically found in contracts like
-- quantified expressions and uses of Update attribute. The default is that
-- this warning is enabled. Modified by use of -gnatw.t/.T.
Warn_On_Suspicious_Modulus_Value : Boolean renames F (X.Warn_On_Suspicious_Modulus_Value);
-- Set to True to generate warnings for suspicious modulus values, as well
-- as negative literals of a modular type. The default is that this warning
-- is enabled. Modified by -gnatw.m/.M.
Warn_On_Unchecked_Conversion : Boolean renames F (X.Warn_On_Unchecked_Conversion);
-- Set to True to generate warnings for unchecked conversions that may have
-- non-portable semantics (e.g. because sizes of types differ). Modified
-- by use of -gnatwz/Z.
Warn_On_Unknown_Compile_Time_Warning : Boolean renames F (X.Warn_On_Unknown_Compile_Time_Warning);
-- Warn on a pragma Compile_Time_Warning whose condition has a value that
-- is not known at compile time. On by default, modified by use
-- of -gnatw_c/_C and set as part of -gnatwa.
Warn_On_Unordered_Enumeration_Type : Boolean renames F (X.Warn_On_Unordered_Enumeration_Type);
-- Set to True to generate warnings for inappropriate uses (comparisons
-- and explicit ranges) on unordered enumeration types (which includes
-- all enumeration types for which pragma Ordered is not given). The
-- default is that this warning is disabled. Modified by -gnat.u/.U.
Warn_On_Unrecognized_Pragma : Boolean renames F (X.Warn_On_Unrecognized_Pragma);
-- Set to True to generate warnings for unrecognized pragmas. The default
-- is that this warning is enabled. Modified by use of -gnatwg/G.
Warn_On_Unrepped_Components : Boolean renames F (X.Warn_On_Unrepped_Components);
-- Set to True to generate warnings for the case of components of record
-- which have a record representation clause but this component does not
-- have a component clause. Modified by use of -gnatw.c/.C.
Warn_On_Warnings_Off : Boolean renames F (X.Warn_On_Warnings_Off);
-- Set to True to generate warnings for use of Pragma Warnings (Off, ent),
-- where either the pragma is never used, or it could be replaced by a
-- pragma Unmodified or Unreferenced. Also generates warnings for pragma
-- Warning (Off, string) which either has no matching pragma Warning On,
-- or where no warning has been suppressed by the use of the pragma.
-- Modified by use of -gnatw.w/.W.
pragma Style_Checks ("M79");
-----------------------------------
-- Saving and Restoring Warnings --
-----------------------------------
function Save_Warnings return Warnings_State;
-- Returns current settings of warnings
procedure Restore_Warnings (W : Warnings_State);
-- Restores current settings of warning flags from W
-----------------
-- Subprograms --
-----------------
type Warning_Family is
-- The "family" indicates the form of warning switch:
(Plain, -- form "-gnatwx"
'.', -- form "-gnatw.x"
'_'); -- form "-gnatw_x"
-- where "x" is a lowercase letter that enables a particular warning.
-- Typically, uppercase of "x" disables the warning, but there are some
-- switches that do not follow that pattern.
function Set_Warning_Switch
(Family : Warning_Family; C : Character) return Boolean;
-- Set the warning switch or switches corresponding to the given family and
-- character. Returns True for valid warning switch, False for invalid.
-- Called for -gnatw... switches, and for pragma Warnings.
procedure Set_GNAT_Mode_Warnings;
-- Called for -gnatg and -gnatw.g to set GNAT mode warnings. This set of
-- warnings is neither a subset nor a superset of -gnatwa.
end Warnsw;