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From: Thomas Huth <thuth@redhat.com>
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Date: Tue, 2 Feb 2016 22:47:35 +0100
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Subject: Re: [Qemu-devel] [PATCH v6 1/5] util: Introduce error reporting
 functions with fatal/abort
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To: Markus Armbruster <armbru@redhat.com>, =?UTF-8?Q?Llu=c3=ads_Vilanova?= <vilanova@ac.upc.edu>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, David Gibson <david@gibson.dropbear.id.au>, qemu-devel@nongnu.org, "Dr . David Alan Gilbert" <dgilbert@redhat.com>

On 02.02.2016 19:53, Markus Armbruster wrote:
> Llu=C3=ADs Vilanova <vilanova@ac.upc.edu> writes:
...

>> diff --git a/include/qemu/error-report.h b/include/qemu/error-report.h
>> index 7ab2355..6c2f142 100644
>> --- a/include/qemu/error-report.h
>> +++ b/include/qemu/error-report.h
>> @@ -43,4 +43,23 @@ void error_report(const char *fmt, ...) GCC_FMT_ATT=
R(1, 2);
>>  const char *error_get_progname(void);
>>  extern bool enable_timestamp_msg;
>> =20
>> +/* Report message and exit with error */
>> +void QEMU_NORETURN error_vreport_fatal(const char *fmt, va_list ap) G=
CC_FMT_ATTR(1, 0);
>> +void QEMU_NORETURN error_report_fatal(const char *fmt, ...) GCC_FMT_A=
TTR(1, 2);
>=20
> This lets people write things like
>=20
>     error_report_fatal("The sky is falling");
>=20
> instead of
>=20
>     error_report("The sky is falling");
>     exit(1);
>=20
> or
>=20
>     fprintf(stderr, "The sky is falling\n");
>     exit(1);
>=20
> I don't think that's an improvement in clarity.

The problem is not the existing code, but that in a couple of new
patches, I've now already seen that people are trying to use

     error_setg(&error_fatal, ... );

to do error reporting - which is IMHO the most ugliest way to do this,
because I'd really not expect error_setg() to (always) exit QEMU when I
quickly read through the sources.
We fortunately do not have that in the sources yet (only some few spots
with error_abort), but to prevent that people start using that, it would
be good to have a error_report_fatal() function instead, I think.

Alternatively, if you really want to see the exit(1) in the sources, I
think this should be mentioned in the coding guidelines ... or are you
fine with error_setg(&error_fatal, ...), Markus?

 Thomas