On 8/6/22 19:08, Dmitry A. Kazakov wrote:
> On 2022-06-08 09:31, Jerry wrote:
>
>> But has no effect on this program;
>>
>> procedure CE_2 is
>>      i : Positive;
>>      j : Integer := 1;
>> begin
>>      i := -j;
>> end CE_2;
>
> I noticed that it requires a user-defined [sub]type AND nested subprogram:
>
>    procedure Test (A : Integer) is
>       subtype T is Integer range 0 .. 42;
>       i : T;
>    begin
>       i := A; -- This will work
>    end;
> begin
>    Test (-1);
>

Are you sure about this ?

I tried ...

procedure Example
is
X : Positive := 5;
begin
loop
X := X - 1;
end loop;
end Example;

.... with the -gnateE and saw this result ...

[rod@orth example]$ ./example

raised CONSTRAINT_ERROR : example.adb:6:14 range check failed
value 0 not in 1..2147483647
[./example]
0x55916975377f Example at example.adb:6
0x559169753b74 Main at b__example.adb:193
[/usr/lib/libc.so.6]
0x7f9230be728e
0x7f9230be7348
[./example]
0x559169753623 _start at start.S:115
0xfffffffffffffffe

On Thursday, October 27, 2022 at 4:57:08 AM UTC-7, roda...@gmail.com wrote:
> On 8/6/22 19:08, Dmitry A. Kazakov wrote:
> > On 2022-06-08 09:31, Jerry wrote:
> >
> >> But has no effect on this program;
> >>
> >> procedure CE_2 is
> >> i : Positive;
> >> j : Integer := 1;
> >> begin
> >> i := -j;
> >> end CE_2;
> >
> > I noticed that it requires a user-defined [sub]type AND nested subprogram:
> >
> > procedure Test (A : Integer) is
> > subtype T is Integer range 0 .. 42;
> > i : T;
> > begin
> > i := A; -- This will work
> > end;
> > begin
> > Test (-1);
> >
> Are you sure about this ?
>
> I tried ...
>
>
> procedure Example
> is
> X : Positive := 5;
> begin
> loop
> X := X - 1;
> end loop;
> end Example;
>
>
> ... with the -gnateE and saw this result ...
>
>
> [rod@orth example]$ ./example
>
> raised CONSTRAINT_ERROR : example.adb:6:14 range check failed
> value 0 not in 1..2147483647
> [./example]
> 0x55916975377f Example at example.adb:6
> 0x559169753b74 Main at b__example.adb:193
> [/usr/lib/libc.so.6]
> 0x7f9230be728e
> 0x7f9230be7348
> [./example]
> 0x559169753623 _start at start.S:115
> 0xfffffffffffffffe

So -gnateE works part of the time?
Jerry

On 29/10/22 11:35, Jerry wrote:
> On Thursday, October 27, 2022 at 4:57:08 AM UTC-7, roda...@gmail.com
wrote:
>> On 8/6/22 19:08, Dmitry A. Kazakov wrote:
>>>
>>> I noticed that it requires a user-defined [sub]type AND nested
subprogram:
>>>
>>> procedure Test (A : Integer) is
>>> subtype T is Integer range 0 .. 42;
>>> i : T;
>>> begin
>>> i := A; -- This will work
>>> end;
>>> begin
>>> Test (-1);
>>>
>> Are you sure about this ?
>>
>> I tried ...
>>
>>
>> procedure Example
>> is
>> X : Positive := 5;
>> begin
>> loop
>> X := X - 1;
>> end loop;
>> end Example;
>>
>>
>> ... with the -gnateE and saw this result ...
>>
>>
>> [rod@orth example]$ ./example
>>
>> raised CONSTRAINT_ERROR : example.adb:6:14 range check failed
>> value 0 not in 1..2147483647
>> [./example]
>> 0x55916975377f Example at example.adb:6
>> 0x559169753b74 Main at b__example.adb:193
>> [/usr/lib/libc.so.6]
>> 0x7f9230be728e
>> 0x7f9230be7348
>> [./example]
>> 0x559169753623 _start at start.S:115
>> 0xfffffffffffffffe
>
> So -gnateE works part of the time?
> Jerry

I've not tested this extensively but assume the extra info would be
shown in most cases.

One exception is the following ...

procedure Example
is
X : Positive := 0 with Unreferenced;
begin
null;
end Example;

.... which shows a compile time warning ...

gprbuild -d -P/home/rod/Desktop/sandbox/ada/example/example.gpr
-XLace_Build_Mode=debug -XLace_Restrictions=xgc -XLace_OS=Linux
-Xrestrictions=xgc
Compile
[Ada] example.adb
example.adb:3:20: warning: value not in range of type
"Standard.Positive" [enabled by default]
example.adb:3:20: warning: Constraint_Error will be raised at run time
[enabled by default]
Bind
[gprbind] example.bexch
[Ada] example.ali
Link
[link] example.adb
[2022-10-29 13:56:36] process terminated successfully, elapsed time: 00.60s

.... and when run ...

[rod@orth example]$ ./example

raised CONSTRAINT_ERROR : example.adb:3 range check failed
[./example]
0x560439f23710 Example at example.adb:3
0x560439f23b00 Main at b__example.adb:193
[/usr/lib/libc.so.6]
0x7f746d52928e
0x7f746d529348
[./example]
0x560439f23623 _start at start.S:115
0xfffffffffffffffe

I'm a little surprised that the compiler shows a warning rather than
an error but I suppose there must be some reason for that.

> One exception is the following ...
>
> procedure Example
> is
> X : Positive := 0 with Unreferenced;
> begin
> null;
> end Example;
>
> ... which shows a compile time warning ...
> [...]
> I'm a little surprised that the compiler shows a warning rather than
> an error but I suppose there must be some reason for that.

HAC (and perhaps other compilers) is stricter on that point:
procedure Example is
X : Positive := 0;
begin
null;
end Example;

example.adb: 2:20-21: error in range constraint: value of expression (0) is out the destination's range, 1 .. 9223372036854775807
E

On 29.10.22 05:10, Rod Kay wrote:

>    I'm a little surprised that the compiler shows a warning rather than an error but I suppose there must be some reason for that.

Formal language reasons aside, a program's author may have wanted
the program to raise an exception. (For example: "There is
a TODO here, so make sure the program never runs past this point.
Assign out of range.")

GNAT just emits a warning for the following program, albeit not the
same warning.
BTW, what would SPARK do here?

procedure Excpt
is
Works_As_Expected: exception;

procedure Test is
begin
if 1 = 1 then
raise Works_As_Expected;
else
raise Program_Error;
end if;
end Test;
begin
Test;
end Excpt;

On Friday, October 28, 2022 at 5:35:20 PM UTC-7, Jerry wrote:
> On Thursday, October 27, 2022 at 4:57:08 AM UTC-7, roda...@gmail.com wrote:
> > On 8/6/22 19:08, Dmitry A. Kazakov wrote:
> > > On 2022-06-08 09:31, Jerry wrote:
> > >
> > >> But has no effect on this program;
> > >>
> > >> procedure CE_2 is
> > >> i : Positive;
> > >> j : Integer := 1;
> > >> begin
> > >> i := -j;
> > >> end CE_2;
> > >
> > > I noticed that it requires a user-defined [sub]type AND nested subprogram:
> > >
> > > procedure Test (A : Integer) is
> > > subtype T is Integer range 0 .. 42;
> > > i : T;
> > > begin
> > > i := A; -- This will work
> > > end;
> > > begin
> > > Test (-1);
> > >
> > Are you sure about this ?
> >
> > I tried ...
> >
> >
> > procedure Example
> > is
> > X : Positive := 5;
> > begin
> > loop
> > X := X - 1;
> > end loop;
> > end Example;
> >
> >
> > ... with the -gnateE and saw this result ...
> >
> >
> > [rod@orth example]$ ./example
> >
> > raised CONSTRAINT_ERROR : example.adb:6:14 range check failed
> > value 0 not in 1..2147483647
> > [./example]
> > 0x55916975377f Example at example.adb:6
> > 0x559169753b74 Main at b__example.adb:193
> > [/usr/lib/libc.so.6]
> > 0x7f9230be728e
> > 0x7f9230be7348
> > [./example]
> > 0x559169753623 _start at start.S:115
> > 0xfffffffffffffffe
> So -gnateE works part of the time?
> Jerry
I simply do not get the robust results others are reporting, and as I noted earlier in this thread, some of the suggested switches are flagged as illegal on macOS

From the docs at https://gcc.gnu.org/onlinedocs/gcc-4.9.4/gnat_ugn_unw/Symbolic-Traceback.html#Symbolic-Traceback:
"Note that this feature is not supported on all platforms. See GNAT.Traceback.Symbolic spec in g-trasym.ads for a complete list of currently supported platforms."

I'm using an older version of GNAT (2017) on Mac and the list of supported platforms is actually in s-trasym.ads and reads as such:
-- The full capability is currently supported on the following targets:

-- HP-UX ia64
-- GNU/Linux x86, x86_64, ia64
-- FreeBSD x86, x86_64
-- Solaris sparc and x86
-- Windows

Maybe newer versions of GNAT are more Mac-friendly. So in order to get both extra information and symbolic tracebacks I've had to write my own garbage-y handler that redirects text output to a file, calls system stuff such as tail and atos, bla bla bla. I hope atos is still supported when I eventually move to ARM. atos I think is Apple's thing that works like addr2line.

BTW, for others attempting this on macOS, turn of address randomization with -no_pie. That is, in my gpr, I have this:
package Linker is
for Default_Switches ("Ada") use ("-Wl,-no_pie");
end Linker;