Confusing location of error in source code

Confusing location of error in source code

[Alejandro Colomar]

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Hi!

I've been confused for some time with a compilation error that
pointed to a slightly-off location.  I wasn't seeing that I used
a temporary variable in a constant expression.  The code could be
reduced to:

$ cat const.c 
int
main(void)
{
	int x = 42;

	_Static_assert(0 || 7 > x, "");
}
$ cc -Wall -Wextra const.c 
const.c: In function ‘main’:
const.c:6:26: error: expression in static assertion is not constant
    6 |         _Static_assert(0 || 7 > x, "");
      |                        ~~^~~~~~~~


I think the appropriate error report should point to this other point:


    6 |         _Static_assert(0 || 7 > x, "");
      |                        ~~~~~~~~~^

Cheers,
Alex

-- 
<http://www.alejandro-colomar.es/>
GPG key fingerprint: A9348594CE31283A826FBDD8D57633D441E25BB5

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Re: Confusing location of error in source code

[Jonathan Wakely]

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On Thu, 31 Aug 2023, 17:05 Alejandro Colomar via Gcc, <gcc@gcc.gnu.org>
wrote:

> Hi!
>
> I've been confused for some time with a compilation error that
> pointed to a slightly-off location.  I wasn't seeing that I used
> a temporary variable in a constant expression.  The code could be
> reduced to:
>
> $ cat const.c
> int
> main(void)
> {
>         int x = 42;
>
>         _Static_assert(0 || 7 > x, "");
> }
> $ cc -Wall -Wextra const.c
> const.c: In function ‘main’:
> const.c:6:26: error: expression in static assertion is not constant
>     6 |         _Static_assert(0 || 7 > x, "");
>       |                        ~~^~~~~~~~
>
>
> I think the appropriate error report should point to this other point:
>
>
>     6 |         _Static_assert(0 || 7 > x, "");
>       |                        ~~~~~~~~~^
>

Please use bugzilla for bug reports.

Re: Confusing location of error in source code

[Alejandro Colomar]

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Hi Jonathan,

On 2023-09-01 08:49, Jonathan Wakely wrote:
> On Thu, 31 Aug 2023, 17:05 Alejandro Colomar via Gcc, <gcc@gcc.gnu.org>
> wrote:
> 
>> Hi!
>>
>> I've been confused for some time with a compilation error that
>> pointed to a slightly-off location.  I wasn't seeing that I used
>> a temporary variable in a constant expression.  The code could be
>> reduced to:
>>
>> $ cat const.c
>> int
>> main(void)
>> {
>>         int x = 42;
>>
>>         _Static_assert(0 || 7 > x, "");
>> }
>> $ cc -Wall -Wextra const.c
>> const.c: In function ‘main’:
>> const.c:6:26: error: expression in static assertion is not constant
>>     6 |         _Static_assert(0 || 7 > x, "");
>>       |                        ~~^~~~~~~~
>>
>>
>> I think the appropriate error report should point to this other point:
>>
>>
>>     6 |         _Static_assert(0 || 7 > x, "");
>>       |                        ~~~~~~~~~^
>>
> 
> Please use bugzilla for bug reports.

Sure, will do.  Thanks!

Alex

> 

-- 
<http://www.alejandro-colomar.es/>
GPG key fingerprint: A9348594CE31283A826FBDD8D57633D441E25BB5


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