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Chris Lattner via llvm-dev

2017-Oct-01 23:01 UTC

[llvm-dev] Is ArrayRef supposed to be immutable?

+1, totally a bug.  That’s the domain of MutableArrayRef.

-Chris
> On Oct 1, 2017, at 6:52 AM, David Blaikie via llvm-dev <llvm-dev at
lists.llvm.org> wrote:
> 
> +1 seems like a bug
> 
> On Sun, Oct 1, 2017 at 12:35 AM Reid Kleckner via llvm-dev <llvm-dev at
lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote:
> It wraps a constant T* and a size_t, so I'm surprised std::sort works.
It shouldn't.
> 
> On Sep 30, 2017 5:22 PM, "Daniel Berlin via llvm-dev"
<llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>>
wrote:
> It seems like ArrayRefs are supposed to be immutable (
> However, as far as i can tell, the iterators are defined wrong to make this
true.
> 
> While 
> ArrayRef<int> Foo(Something);
> Foo[0] = 5;
> 
> will give a compile time error.
> 
> something like:
> 
> ArrayRef<int> Foo(Something);
> std::sort(Foo.begin(), Foo.end());
> 
> Will work fine.
> 
> Is this expected?
> 
> (FWIW: I expected this to only work with a MutableArrayRef)
> 
> 
> 
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
<http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
> 
> 
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
<http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
> _______________________________________________
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> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
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Zachary Turner via llvm-dev

2017-Oct-02 16:37 UTC

head link

[llvm-dev] Is ArrayRef supposed to be immutable?

It's possible I'm missing something, but I can't reproduce this:

  std::vector<int> A = { 4, 15, 42 , 16, 8, 23};
  ArrayRef<int> B(A);
  std::sort(B.begin(), B.end());

fails to compile for me.

ArrayRef<T>::iterator is specified as `const T *`, so I'm not seeing
how
this could happen?

On Sun, Oct 1, 2017 at 4:01 PM Chris Lattner via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> +1, totally a bug.  That’s the domain of MutableArrayRef.
>
> -Chris
>
> On Oct 1, 2017, at 6:52 AM, David Blaikie via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
> +1 seems like a bug
>
> On Sun, Oct 1, 2017 at 12:35 AM Reid Kleckner via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> It wraps a constant T* and a size_t, so I'm surprised std::sort
works. It
>> shouldn't.
>>
>> On Sep 30, 2017 5:22 PM, "Daniel Berlin via llvm-dev" <
>> llvm-dev at lists.llvm.org> wrote:
>>
>> It seems like ArrayRefs are supposed to be immutable (
>> However, as far as i can tell, the iterators are defined wrong to make
>> this true.
>>
>> While
>> ArrayRef<int> Foo(Something);
>> Foo[0] = 5;
>>
>> will give a compile time error.
>>
>> something like:
>>
>> ArrayRef<int> Foo(Something);
>> std::sort(Foo.begin(), Foo.end());
>>
>> Will work fine.
>>
>> Is this expected?
>>
>> (FWIW: I expected this to only work with a MutableArrayRef)
>>
>>
>>
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>>
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
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Daniel Berlin via llvm-dev

2017-Oct-02 17:31 UTC

head link

[llvm-dev] Is ArrayRef supposed to be immutable?

On Mon, Oct 2, 2017 at 9:37 AM, Zachary Turner via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> It's possible I'm missing something, but I can't reproduce
this:
>
>   std::vector<int> A = { 4, 15, 42 , 16, 8, 23};
>   ArrayRef<int> B(A);
>   std::sort(B.begin(), B.end());
>
> fails to compile for me.
>
>As later mentioned, it was transient and appears to have only affected some
version  :)
Because of that, i stopped looking into it after tracking it down to what
appears to be a hilarious miscompile of clang.

> ArrayRef<T>::iterator is specified as `const T *`, so I'm not
seeing how
> this could happen?
>
> On Sun, Oct 1, 2017 at 4:01 PM Chris Lattner via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> +1, totally a bug.  That’s the domain of MutableArrayRef.
>>
>> -Chris
>>
>> On Oct 1, 2017, at 6:52 AM, David Blaikie via llvm-dev <
>> llvm-dev at lists.llvm.org> wrote:
>>
>> +1 seems like a bug
>>
>> On Sun, Oct 1, 2017 at 12:35 AM Reid Kleckner via llvm-dev <
>> llvm-dev at lists.llvm.org> wrote:
>>
>>> It wraps a constant T* and a size_t, so I'm surprised std::sort
works.
>>> It shouldn't.
>>>
>>> On Sep 30, 2017 5:22 PM, "Daniel Berlin via llvm-dev"
<
>>> llvm-dev at lists.llvm.org> wrote:
>>>
>>> It seems like ArrayRefs are supposed to be immutable (
>>> However, as far as i can tell, the iterators are defined wrong to
make
>>> this true.
>>>
>>> While
>>> ArrayRef<int> Foo(Something);
>>> Foo[0] = 5;
>>>
>>> will give a compile time error.
>>>
>>> something like:
>>>
>>> ArrayRef<int> Foo(Something);
>>> std::sort(Foo.begin(), Foo.end());
>>>
>>> Will work fine.
>>>
>>> Is this expected?
>>>
>>> (FWIW: I expected this to only work with a MutableArrayRef)
>>>
>>>
>>>
>>> _______________________________________________
>>> LLVM Developers mailing list
>>> llvm-dev at lists.llvm.org
>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>
>>>
>>> _______________________________________________
>>> LLVM Developers mailing list
>>> llvm-dev at lists.llvm.org
>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>>
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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llvm dev - Oct 2017 - Is ArrayRef supposed to be immutable?

[llvm-dev] Is ArrayRef supposed to be immutable?

[llvm-dev] Is ArrayRef supposed to be immutable?

[llvm-dev] Is ArrayRef supposed to be immutable?