[Ada] Implement -gnat-p switch (cancel previous -gnatp)
Arnaud Charlet
charlet@adacore.com
Wed Jun 16 16:41:00 GMT 2010
This patch implements a new switch -gnat-p which cancels the effect of
a previous -gnatp switch. The following test program:
procedure GnatMP is
N : Natural := 0;
function Zero return Natural is
begin
return N;
end Zero;
begin
N := Zero;
N := N - 1;
end GnatMP;
compiled with switches -gnatp -gnat-p and run generates the
following output:
raised CONSTRAINT_ERROR : gnatmp.adb:11 range check failed
Tested on x86_64-pc-linux-gnu, committed on trunk
2010-06-16 Robert Dewar <dewar@adacore.com>
* back_end.adb (Switch_Subsequently_Cancelled): New function
Move declarations to package body level to support this change
* back_end.ads (Switch_Subsequently_Cancelled): New function
* gnat_ugn.texi: Document -gnat-p switch
* switch-c.adb (Scan_Front_End_Switches): Implement -gnat-p switch
* ug_words: Add entry for -gnat-p (UNSUPPRESS_ALL)
* usage.adb: Add line for -gnat-p switch
* vms_data.ads: Add entry for UNSUPPRESS_ALL (-gnat-p)
-------------- next part --------------
Index: switch-c.adb
===================================================================
--- switch-c.adb (revision 160834)
+++ switch-c.adb (working copy)
@@ -23,6 +23,7 @@
-- --
------------------------------------------------------------------------------
+with Back_End; use Back_End;
with Debug; use Debug;
with Lib; use Lib;
with Osint; use Osint;
@@ -662,20 +663,27 @@ package body Switch.C is
when 'p' =>
Ptr := Ptr + 1;
- -- Set all specific options as well as All_Checks in the
- -- Suppress_Options array, excluding Elaboration_Check, since
- -- this is treated specially because we do not want -gnatp to
- -- disable static elaboration processing.
-
- for J in Suppress_Options'Range loop
- if J /= Elaboration_Check then
- Suppress_Options (J) := True;
- end if;
- end loop;
+ -- Skip processing if cancelled by subsequent -gnat-p
+
+ if Switch_Subsequently_Cancelled ("p") then
+ Store_Switch := False;
- Validity_Checks_On := False;
- Opt.Suppress_Checks := True;
- Opt.Enable_Overflow_Checks := False;
+ else
+ -- Set all specific options as well as All_Checks in the
+ -- Suppress_Options array, excluding Elaboration_Check,
+ -- since this is treated specially because we do not want
+ -- -gnatp to disable static elaboration processing.
+
+ for J in Suppress_Options'Range loop
+ if J /= Elaboration_Check then
+ Suppress_Options (J) := True;
+ end if;
+ end loop;
+
+ Validity_Checks_On := False;
+ Opt.Suppress_Checks := True;
+ Opt.Enable_Overflow_Checks := False;
+ end if;
-- Processing for P switch
@@ -933,6 +941,7 @@ package body Switch.C is
-- Processing for z switch
when 'z' =>
+
-- -gnatz must be the first and only switch in Switch_Chars,
-- and is a two-letter switch.
@@ -1027,10 +1036,31 @@ package body Switch.C is
Ada_Version_Explicit := Ada_Version;
end if;
- -- Ignore extra switch character
+ -- Switch cancellation, currently only -gnat-p is allowed.
+ -- All we do here is the error checking, since the actual
+ -- processing for switch cancellation is done by calls to
+ -- Switch_Subsequently_Cancelled at the appropriate point.
- when '/' | '-' =>
- Ptr := Ptr + 1;
+ when '-' =>
+
+ -- Simple ignore -gnat-p
+
+ if Switch_Chars = "-gnat-p" then
+ return;
+
+ -- Any other occurrence of minus is ignored. This is for
+ -- maximum compatibility with previous version which ignored
+ -- all occurrences of minus.
+
+ else
+ Store_Switch := False;
+ Ptr := Ptr + 1;
+ end if;
+
+ -- We ignore '/' in switches, this is historical, still needed???
+
+ when '/' =>
+ Store_Switch := False;
-- Anything else is an error (illegal switch character)
Index: usage.adb
===================================================================
--- usage.adb (revision 160834)
+++ usage.adb (working copy)
@@ -598,4 +598,9 @@ begin
Write_Line ("Allow Ada 2005 extensions");
end if;
+ -- Line for -gnat-p switch
+
+ Write_Switch_Char ("-p");
+ Write_Line ("Cancel effect of previous -gnatp switch");
+
end Usage;
Index: ug_words
===================================================================
--- ug_words (revision 160834)
+++ ug_words (working copy)
@@ -85,6 +85,7 @@ gcc -c ^ GNAT COMPILE
-gnatN ^ /INLINE=FULL
-gnato ^ /CHECKS=OVERFLOW
-gnatp ^ /CHECKS=SUPPRESS_ALL
+-gnat-p ^ /CHECKS=UNSUPPRESS_ALL
-gnatP ^ /POLLING
-gnatR ^ /REPRESENTATION_INFO
-gnatR0 ^ /REPRESENTATION_INFO=NONE
Index: gnat_ugn.texi
===================================================================
--- gnat_ugn.texi (revision 160834)
+++ gnat_ugn.texi (working copy)
@@ -4294,7 +4294,12 @@ controlled by this switch (division by z
@item -gnatp
@cindex @option{-gnatp} (@command{gcc})
-Suppress all checks. See @ref{Run-Time Checks} for details.
+Suppress all checks. See @ref{Run-Time Checks} for details. This switch
+has no effect if cancelled by a subsequent @option{-gnat-p} switch.
+
+@item -gnat-p
+@cindex @option{-gnat-p} (@command{gcc})
+Cancel effect of previous @option{-gnatp} switch.
@item -gnatP
@cindex @option{-gnatP} (@command{gcc})
@@ -4591,6 +4596,9 @@ The switches
@option{-gnatzc} and @option{-gnatzr} may not be combined with any other
switches, and only one of them may appear in the command line.
+@item
+The switch @option{-gnat-p} may not be combined with any other switch.
+
@ifclear vms
@item
Once a ``y'' appears in the string (that is a use of the @option{-gnaty}
@@ -6622,6 +6630,16 @@ year). The compiler will generate code b
the condition being checked is true, which can result in disaster if
that assumption is wrong.
+The @option{-gnatp} switch has no effect if a subsequent
+@option{-gnat-p} switch appears.
+
+@item -gnat-p
+@cindex @option{-gnat-p} (@command{gcc})
+@cindex Suppressing checks
+@cindex Checks, suppressing
+@findex Suppress
+This switch cancels the effect of a previous @option{gnatp} switch.
+
@item -gnato
@cindex @option{-gnato} (@command{gcc})
@cindex Overflow checks
Index: back_end.adb
===================================================================
--- back_end.adb (revision 160834)
+++ back_end.adb (working copy)
@@ -42,6 +42,29 @@ with Types; use Types;
package body Back_End is
+ type Arg_Array is array (Nat) of Big_String_Ptr;
+ type Arg_Array_Ptr is access Arg_Array;
+ -- Types to access compiler arguments
+
+ Next_Arg : Pos := 1;
+ -- Next argument to be scanned by Scan_Compiler_Arguments. We make this
+ -- global so that it can be accessed by Switch_Subsequently_Cancelled.
+
+ flag_stack_check : Int;
+ pragma Import (C, flag_stack_check);
+ -- Indicates if stack checking is enabled, imported from toplev.c
+
+ save_argc : Nat;
+ pragma Import (C, save_argc);
+ -- Saved value of argc (number of arguments), imported from toplev.c
+
+ save_argv : Arg_Array_Ptr;
+ pragma Import (C, save_argv);
+ -- Saved value of argv (argument pointers), imported from toplev.c
+
+ function Len_Arg (Arg : Pos) return Nat;
+ -- Determine length of argument number Arg on original gnat1 command line
+
-------------------
-- Call_Back_End --
-------------------
@@ -122,37 +145,30 @@ package body Back_End is
gigi_operating_mode => Mode);
end Call_Back_End;
+ -------------
+ -- Len_Arg --
+ -------------
+
+ function Len_Arg (Arg : Pos) return Nat is
+ begin
+ for J in 1 .. Nat'Last loop
+ if save_argv (Arg).all (Natural (J)) = ASCII.NUL then
+ return J - 1;
+ end if;
+ end loop;
+
+ raise Program_Error;
+ end Len_Arg;
+
-----------------------------
-- Scan_Compiler_Arguments --
-----------------------------
procedure Scan_Compiler_Arguments is
- Next_Arg : Pos := 1;
-
- type Arg_Array is array (Nat) of Big_String_Ptr;
- type Arg_Array_Ptr is access Arg_Array;
-
- flag_stack_check : Int;
- pragma Import (C, flag_stack_check);
- -- Import from toplev.c
-
- save_argc : Nat;
- pragma Import (C, save_argc);
- -- Import from toplev.c
-
- save_argv : Arg_Array_Ptr;
- pragma Import (C, save_argv);
- -- Import from toplev.c
Output_File_Name_Seen : Boolean := False;
-- Set to True after having scanned file_name for switch "-gnatO file"
- -- Local functions
-
- function Len_Arg (Arg : Pos) return Nat;
- -- Determine length of argument number Arg on the original command line
- -- from gnat1.
-
procedure Scan_Back_End_Switches (Switch_Chars : String);
-- Procedure to scan out switches stored in Switch_Chars. The first
-- character is known to be a valid switch character, and there are no
@@ -165,21 +181,6 @@ package body Back_End is
-- switches must still be scanned to skip "-o" or internal GCC switches
-- with their argument.
- -------------
- -- Len_Arg --
- -------------
-
- function Len_Arg (Arg : Pos) return Nat is
- begin
- for J in 1 .. Nat'Last loop
- if save_argv (Arg).all (Natural (J)) = ASCII.NUL then
- return J - 1;
- end if;
- end loop;
-
- raise Program_Error;
- end Len_Arg;
-
----------------------------
-- Scan_Back_End_Switches --
----------------------------
@@ -296,4 +297,31 @@ package body Back_End is
end loop;
end Scan_Compiler_Arguments;
+ -----------------------------------
+ -- Switch_Subsequently_Cancelled --
+ -----------------------------------
+
+ function Switch_Subsequently_Cancelled (C : String) return Boolean is
+ Arg : Pos;
+
+ begin
+ Arg := Next_Arg + 1;
+ while Arg < save_argc loop
+ declare
+ Argv_Ptr : constant Big_String_Ptr := save_argv (Arg);
+ Argv_Len : constant Nat := Len_Arg (Arg);
+ Argv : constant String :=
+ Argv_Ptr (1 .. Natural (Argv_Len));
+ begin
+ if Argv = "-gnat-" & C then
+ return True;
+ end if;
+ end;
+
+ Arg := Arg + 1;
+ end loop;
+
+ return False;
+ end Switch_Subsequently_Cancelled;
+
end Back_End;
Index: back_end.ads
===================================================================
--- back_end.ads (revision 160834)
+++ back_end.ads (working copy)
@@ -6,7 +6,7 @@
-- --
-- S p e c --
-- --
--- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2010, 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- --
@@ -61,4 +61,11 @@ package Back_End is
-- Any processed switches that influence the result of a compilation must
-- be added to the Compilation_Arguments table.
+ function Switch_Subsequently_Cancelled (C : String) return Boolean;
+ -- This function is called from Scan_Front_End_Switches. It determines if
+ -- the switch currently being scanned is followed by a switch of the form
+ -- "-gnat-" & C, where C is the argument. If so, then True is returned,
+ -- and Scan_Front_End_Switches will cancel the effect of the switch. If
+ -- no such switch is found, False is returned.
+
end Back_End;
Index: vms_data.ads
===================================================================
--- vms_data.ads (revision 160834)
+++ vms_data.ads (working copy)
@@ -1253,7 +1253,9 @@ package VMS_Data is
"STACK " &
"-fstack-check " &
"SUPPRESS_ALL " &
- "-gnatp";
+ "-gnatp " &
+ "UNSUPPRESS_ALL " &
+ "-gnat-p";
-- /NOCHECKS
-- /CHECKS[=(keyword[,...])]
--
@@ -1267,47 +1269,50 @@ package VMS_Data is
-- You may specify one or more of the following keywords to the /CHECKS
-- qualifier to modify this behavior:
--
- -- DEFAULT The behavior described above. This is the default
- -- if the /CHECKS qualifier is not present on the
- -- command line. Same as /NOCHECKS.
- --
- -- OVERFLOW Enables overflow checking for integer operations and
- -- checks for access before elaboration on subprogram
- -- calls. This causes GNAT to generate slower and larger
- -- executable programs by adding code to check for both
- -- overflow and division by zero (resulting in raising
- -- "Constraint_Error" as required by Ada semantics).
- -- Similarly, GNAT does not generate elaboration check
- -- by default, and you must specify this keyword to
- -- enable them.
- --
- -- Note that this keyword does not affect the code
- -- generated for any floating-point operations; it
- -- applies only to integer operations. For floating-point,
- -- GNAT has the "Machine_Overflows" attribute set to
- -- "False" and the normal mode of operation is to generate
- -- IEEE NaN and infinite values on overflow or invalid
- -- operations (such as dividing 0.0 by 0.0).
- --
- -- ELABORATION Enables dynamic checks for access-before-elaboration
- -- on subprogram calls and generic instantiations.
- --
- -- ASSERTIONS The pragmas "Assert" and "Debug" normally have no
- -- effect and are ignored. This keyword causes "Assert"
- -- and "Debug" pragmas to be activated, as well as
- -- "Check", "Precondition" and "Postcondition" pragmas.
- --
- -- SUPPRESS_ALL Suppress all runtime checks as though you have "pragma
- -- Suppress (all_checks)" in your source. Use this switch
- -- to improve the performance of the code at the expense
- -- of safety in the presence of invalid data or program
- -- bugs.
+ -- DEFAULT The behavior described above. This is the default
+ -- if the /CHECKS qualifier is not present on the
+ -- command line. Same as /NOCHECKS.
+ --
+ -- OVERFLOW Enables overflow checking for integer operations and
+ -- checks for access before elaboration on subprogram
+ -- calls. This causes GNAT to generate slower and larger
+ -- executable programs by adding code to check for both
+ -- overflow and division by zero (resulting in raising
+ -- "Constraint_Error" as required by Ada semantics).
+ -- Similarly, GNAT does not generate elaboration check
+ -- by default, and you must specify this keyword to
+ -- enable them.
+ --
+ -- Note that this keyword does not affect the code
+ -- generated for any floating-point operations; it
+ -- applies only to integer operations. For the case of
+ -- floating-point, GNAT has the "Machine_Overflows"
+ -- attribute set to "False" and the normal mode of
+ -- operation is to generate IEEE NaN and infinite values
+ -- on overflow or invalid operations (such as dividing
+ -- 0.0 by 0.0).
+ --
+ -- ELABORATION Enables dynamic checks for access-before-elaboration
+ -- on subprogram calls and generic instantiations.
+ --
+ -- ASSERTIONS The pragmas "Assert" and "Debug" normally have no
+ -- effect and are ignored. This keyword causes "Assert"
+ -- and "Debug" pragmas to be activated, as well as
+ -- "Check", "Precondition" and "Postcondition" pragmas.
+ --
+ -- SUPPRESS_ALL Suppress all runtime checks as though you have
+ -- "pragma Suppress (all_checks)" in your source. Use
+ -- this switch to improve the performance of the code at
+ -- the expense of safety in the presence of invalid data
+ -- or program bugs.
--
- -- DEFAULT Suppress the effect of any option OVERFLOW or
- -- ASSERTIONS.
+ -- UNSUPPRESS_ALL Cancels effect of previous SUPPRESS_ALL.
--
- -- FULL (D) Similar to OVERFLOW, but suppress the effect of any
- -- option ELABORATION or SUPPRESS_ALL.
+ -- DEFAULT Suppress the effect of any option OVERFLOW or
+ -- ASSERTIONS.
+ --
+ -- FULL (D) Similar to OVERFLOW, but suppress the effect of any
+ -- option ELABORATION or SUPPRESS_ALL.
--
-- These keywords only control the default setting of the checks. You
-- may modify them using either "Suppress" (to remove checks) or
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