[Bug c++/85460] New: g++ does not check incompatible type

[zhonghao at pku dot org.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85460

            Bug ID: 85460
           Summary: g++ does not check incompatible type
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhonghao at pku dot org.cn
  Target Milestone: ---

This is my test case:

enum _Ios_Iostate
{
};

template<typename>
struct basic_istream
{
  struct sentry
  {
    sentry(basic_istream& )
    {
      _Ios_Iostate __err ;
      __err |=1;
    }
  };
};

g++ does not produce any errors, when 1 is assigned to __err. However, when
clang compiles this code, it produces the following message:
error: assigning to '_Ios_Iostate' from incompatible type 'int'
          __err |=1;
                ^ ~
    1 error generated.