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Re: [PATCH] Decorate string_view members with nonnull attribute


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.

Martin


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