[PATCH] Decorate string_view members with nonnull attribute

[Jonathan Wakely]

On 14/06/18 10:46 -0600, Martin Sebor wrote:
>On 06/13/2018 10:30 AM, Jonathan Wakely wrote:
>>The C++ committee has confirmed that passing a null pointer to the
>>unary basic_string_view constructor is undefined. This removes the check
>>from our implementation, and adds the nonnull attribute to warn when the
>>compiler can detect undefined input.
>>
>>Any objections to this change?
>
>I have a general question about using the new C++ attributes in
>libstdc++ (standard or otherwise): what does C++ have to say about
>programs that define macros with the same names?  E.g., is this
>a valid program?
>
>  #define nonnull "..."
>  ...
>  #include <string_view>
>
>How about:
>
>  #define noreturn "..."
>  ...
>  #include <string_view>
>
>The view in WG14 is that the corresponding C programs (if C2X
>were to adopt the proposed C++ attributes) would be valid and
>that it's up to implementations to make it work.

Good point, I suppose I have to use __attribute__((__nonnull__))
instead. The reason I didn't is that I find the grammar for the
position of C++11 attributes much easier to understand. But in this
instance the same location works for either.