[Bug c++/67795] New: Wrong code generated for conditional expression with cast

[frankhb1989 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67795

            Bug ID: 67795
           Summary: Wrong code generated for conditional expression with
                    cast
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: frankhb1989 at gmail dot com
  Target Milestone: ---

Case:
// g++ -std=c++1y
#include <iostream>
#include <string>
#include <experimental/string_view>

using namespace std;
using namespace experimental;

string_view&
erase_left(size_t n, string_view& s)
{
        return static_cast<string_view&>(n != 0 ? (s.remove_prefix(n), s) : s);
//      return n != 0 ? (s.remove_prefix(n), s) : s;
}

int main()
{
        string_view sv("abcde");
        cout << erase_left(3, sv).to_string() << endl; // expected "de"
}

The output is garbage, using i686-w64-mingw32-g++ from MSYS2. However,
x86_64-w64-mingw32-clang++ is OK. So I suspect it is a frontend bug.