[PATCH] Ensure std::getline always 0-terminates string.

[Reimar Döffinger via cfe-commits]

On 20 November 2017 22:19:04 CET, Volodymyr Sapsai <vsapsai at apple.com> wrote:
>On Nov 20, 2017, at 11:32, Reimar Döffinger <Reimar.Doeffinger at gmx.de>
>wrote:
>> 
>> On Mon, Nov 20, 2017 at 11:02:13AM -0800, Volodymyr Sapsai wrote:
>>>>     catch (...)
>>>>     {
>>>> +        if (__n > 0)
>>>> +            *__s = char_type();
>>>>         this->__set_badbit_and_consider_rethrow();
>>>>     }
>>> 
>>> or maybe something else?
>> 
>> That one (note that the __set_badbit_and_consider_rethrow
>> will never re-throw in this case).
>
>But by #define _LIBCPP_NO_EXCEPTIONS 1 you exclude this block at
>preprocessing step
>
>>  #ifndef _LIBCPP_NO_EXCEPTIONS
>>      }
>>      catch (...)
>>      {
>> +        if (__n > 0)
>> +            *__s = char_type();
>>          this->__set_badbit_and_consider_rethrow();
>>      }
>>  #endif  // _LIBCPP_NO_EXCEPTIONS
>
>And looks like getline_pointer_size_exception.pass.cpp doesn’t execute
>this code.

Yes, that was complete nonsense, I somehow always read #ifdef where there was an #ifndef...
Not sure then if that 0 termination should be there (and be tested) or better to not have it in the exception case at all (I haven't checked if the exception is always re-thrown or not, which might be relevant).
I am a bit unclear about that whole code there that catches exceptions and sets the bad bit and how it maps to the specification.