[v3, patch, variant] user-defined operator& and std::variant

2016-09-03 Thread Mikhail Strelnikov
Hello,

Following code does not compile,

#include 

namespace n
{
template
void operator&(T) {}
struct s{};
}

int main()
{
std::variant v;
std::get(v);
}

error: include/c++/7.0.0/variant:315:4: error: invalid static_cast

diff -r -u a/libstdc++-v3/include/std/variant b/libstdc++-v3/include/std/variant
--- a/libstdc++-v3/include/std/variant 2016-08-26 13:34:30.823029400 +0300
+++ b/libstdc++-v3/include/std/variant 2016-09-03 18:01:26.431299300 +0300
@@ -312,7 +312,7 @@
   _M_storage() const
   {
  return const_cast(
-  static_cast(&_M_first._M_storage));
+  static_cast(std::__addressof(_M_first._M_storage)));
   }

   union


Re: [v3, patch, variant] user-defined operator& and std::variant

2016-09-05 Thread Tim Shen
On Sat, Sep 3, 2016 at 12:46 PM, Mikhail Strelnikov wrote:
> Hello,
>
> Following code does not compile,
>
> #include 
>
> namespace n
> {
> template
> void operator&(T) {}
> struct s{};
> }
>
> int main()
> {
> std::variant v;
> std::get(v);
> }
>
> error: include/c++/7.0.0/variant:315:4: error: invalid static_cast
>
> diff -r -u a/libstdc++-v3/include/std/variant 
> b/libstdc++-v3/include/std/variant
> --- a/libstdc++-v3/include/std/variant 2016-08-26 13:34:30.823029400 +0300
> +++ b/libstdc++-v3/include/std/variant 2016-09-03 18:01:26.431299300 +0300
> @@ -312,7 +312,7 @@
>_M_storage() const
>{
>   return const_cast(
> -  static_cast(&_M_first._M_storage));
> +  static_cast(std::__addressof(_M_first._M_storage)));
>}
>
>union

Thanks for the patch! Tested on x86_64-linux-gnu and committed as r239996.

I changed std::__addressof to std::addressof since it's standardized
since C++11.


-- 
Regards,
Tim Shen