Re: [boost] [config] [regression] Regression test failures due to compiler bugs -- your advice needed

Subject: Re: [boost] [config] [regression] Regression test failures due to compiler bugs -- your advice needed
From: Andrzej Krzemienski (akrzemi1_at_[hidden])
Date: 2015-01-21 16:10:18

2015-01-21 21:56 GMT+01:00 Peter Dimov <lists_at_[hidden]>:

> Andrzej Krzemienski wrote:
>
>> 2015-01-21 16:41 GMT+01:00 Peter Dimov <lists_at_[hidden]>:
>> > On the doc page, you state that these bugs are present in all MSVC >
>> versions, but on the tests page, I only see one failure, with msvc-10.0, >
>> everything else is green (or, in some cases, missing.)
>>
>> You are right. I need to check if I didn't loose some tests. But back to
>> my original request, did what I say makes sense?
>>
>
> I'd like to know more about what is failing where before I venture an
> opinion about your original request.
>
> An optional<T&> that fails silently for certain T's in a quite insidious
> way on a wide array of popular compilers, including all versions of MSVC,
> should perhaps be disabled for those T's outright, instead of the failures
> being marked. Users do not consult the markup when using optional<> and
> even if they did, optional<int const&> is most likely to occur in generic
> code, not on its own. This will result in some very hard to track bugs.
>

Are you saying that on a compiler where an operation on optional<T&> might
give wrong run-time result, the operation should be disabled (render a
compile-time error)? If so, I agree, and intend to do it at some point. But
even then I should indicate somehow in regression tests that I expect
different results in gcc and in msvc.

Regards,
&rzej