Re: [PATCH] Change the default for Mixed declarations.

[Markus Armbruster <armbru@redhat.com>]

Alex Bennée <alex.bennee@linaro.org> writes:

> Juan Quintela <quintela@redhat.com> writes:
>
>> Daniel P. Berrangé <berrange@redhat.com> wrote:
>>> On Tue, Feb 14, 2023 at 05:07:38PM +0100, Juan Quintela wrote:
>>>> Hi
>>>> 
>>>> I want to enter a discussion about changing the default of the style
>>>> guide.
>>>> 
>>>> There are several reasons for that:
>>>> - they exist since C99 (i.e. all supported compilers support them)
>>>> - they eliminate the posibility of an unitialized variable.
>>>
>>> Actually they don't do that reliably. In fact, when combined
>>> with usage of 'goto', they introduce uninitialized variables,
>>> despite the declaration having an initialization present, and
>>> thus actively mislead reviewers into thinking their code is
>>> safe.
>>
>> Wait a minute.
>> If you use goto, you are already in special rules.
>>
>> And don't get confused, I fully agree when using goto for two reasons:
>> - performance
>>   if you show that the code is x% faster when using goto, it is
>>   justified.  It is even better if you send a bug report to gcc/clang,
>>   but I will not opose that use.
>
> I await a clear example in the context of QEMU - there is almost always
> a better way to structure things.
>
>> - code clearity
>>   Some code (basically error paths) are clearer with goto that without
>>   them.
>
> Now we have g_auto* and lock guards we should encourage their use. goto
> error_path is a relic of a simpler time ;-)

Only 8004 places to "modernize" (not counting generated code and
documentation) before presence of goto ceases to be a concern.

[...]