[PATCH 1/4] Revert "2017-10-04 Petr Ovtchenkov <ptr@void-ptr.info>"

[Jonathan Wakely]

On 16/11/17 11:39 +0000, Jonathan Wakely wrote:
>On 16/11/17 14:35 +0300, Petr Ovtchenkov wrote:
>>On Thu, 16 Nov 2017 10:56:29 +0000
>>Jonathan Wakely <jwakely@redhat.com> wrote:
>>
>>>On 10/10/17 22:55 +0300, Petr Ovtchenkov wrote:
>>>>This reverts commit 0dfbafdf338cc6899d146add5161e52efb02c067
>>>>(svn r253417).
>>>
>>>I'm not even going to bother to review patches sent without any
>>>explanation or rationale for the change.
>>
>>https://gcc.gnu.org/ml/libstdc++/2017-11/msg00044.html
>>
>>Along with "violate principles of C++ objects life cycle",
>>the side-effect is
>>
>> - Make istreambuf_iterator::_M_sbuf immutable
>> - streambuf_iterator: avoid debug-dependent behaviour
>>
>>I should underline, that "_M_sbuf = 0" when istreambuf_iterator
>>see eof, lead to cripple lifecycle of istreambuf_iterator
>>object and [almost] block usage of istreambuf_iterator
>>for entities other then immutable files.
>>
>>All tests from 24_iterators and 25_algorithms passed,
>>so I expect it conform to Standard.
>>
>>This is series of patches, not single patch because
>>I keep in mind technology aspect---easy transfer
>>to branches other then trunk.
>>
>>>
>>>I will repeat what Paolo said: changing the ABI is not acceptable.
>>
>>I will repeat special for you:
>>
>><snip>
>>Is we really worry about frozen sizeof of instantiated template?
>>(Removed private template member).
>>
>>If yes, than
>>
>>  int_type __dummy;
>>
>>is our all.
>></snip>
>>
>>I.e. problem can be easy resolved---i.e. ABI will not suffer, if we will
>
>What about other translation units which have inlined the old
>definition of the template, and expect to find a buffered character in
>that member?

In other words, the ABI is not just the "frozen sizeof".

>>reach some consensus on the main issue.
>
>We don't have any consensus, in fact I don't see anybody agreeing with
>you, and I've previously stated I don't want to support your use case:
>https://gcc.gnu.org/ml/libstdc++/2017-09/msg00100.html
>