Re: [gentoo-dev] Changing policy about -Werror

[Richard Yao]

On 09/13/2018 07:36 AM, Richard Yao wrote:
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>> On Sep 12, 2018, at 6:55 PM, Thomas Deutschmann <whissi@g.o> wrote:
>>
>>> On 2018-09-12 16:50, Rich Freeman wrote:
>>> There is also the case where we want these warnings to block
>>> installation, because the risk of there being a problem is too great.
>>
>> I really disagree with that. So many devs have already said multiple
>> times in this thread that "-Werror" is only turning existing warnings
>> into fatal errors but "-Werror" itself doesn't add any new checks and
>> more often requires "-O3" to be useful.
> The way that compilers work is that the warnings are generated in the front end while the optimization level affects the backend. That means that -O3 has no effect on the code that does error generation. This remark about -O3 being needed to make -Werror useful is just plain wrong.
I had a discussion off list about this. My remarks on this were
incorrect. However, I strongly disagree that -O3 is necessary for
diagnostics to be useful.
>> So let's turn this around: Please show us a *real* case within Gentoo
>> where "-Werror" prevented a real problem which wouldn't otherwise being
>> noticed. E.g. show us a package which was merged on user's system,
>> replacing a working previous version of that package causing *real*
>> problems which could have been prevented if package would have set
>> "-Werror".
>>
>> Unless you can do that we don't really need to discuss this. Simply
>> because everyone interested in "-Werror" *can* set that flag via CFLAGS,
>> even just per package, whereas the majority, not interested in this,
>> cannot do the same to filter "-Werror". Nobody advocating for "-Werror"
>> replied to that fact yet.
>>
>>
>> --
>> Regards,
>> Thomas Deutschmann / Gentoo Linux Developer
>> C4DD 695F A713 8F24 2AA1 5638 5849 7EE5 1D5D 74A5
>>
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