[LLVMdev] Addressing const reference in ArrayRef

[David Blaikie]

On Fri, Aug 22, 2014 at 11:22 AM, Duncan P. N. Exon Smith
<dexonsmith at apple.com> wrote:
>
>> On 2014-Aug-22, at 10:43, David Blaikie <dblaikie at gmail.com> wrote:
>>
>> Yep - the convenience of one-element->ArrayRef is "cute" at best, I
>> think. Having to wrap it doesn't seem detrimental. Would have to look
>> at some numbers, though (if we could easily gather the number of
>> instances of this - I'm not sure of the easiest way to do that, given
>> the build system likes to stop after it sees an error).
>
> diff --git a/include/llvm/ADT/ArrayRef.h b/include/llvm/ADT/ArrayRef.h
> index 0351cf5..79f14da 100644
> --- a/include/llvm/ADT/ArrayRef.h
> +++ b/include/llvm/ADT/ArrayRef.h
> @@ -68,7 +68,7 @@ namespace llvm {
>      /*implicit*/ ArrayRef(NoneType) : Data(nullptr), Length(0) {}
>
>      /// Construct an ArrayRef from a single element.
> -    /*implicit*/ ArrayRef(const T &OneElt)
> +    __attribute__((deprecated)) /*implicit*/ ArrayRef(const T &OneElt)
>        : Data(&OneElt), Length(1) {}
>
>      /// Construct an ArrayRef from a pointer and length.
>
> and rebuilding LLVM and Clang gives me:
>
> $ ninja 2>&1 | grep -e Wdeprecated-declarations | wc -l
>     6083

Uniqued? I imagine a few are in headers.

>
> This includes forwards from the `makeArrayRef()` helper.