[Bug c++/36744] New: function modifying argument received by-value affects caller's variable when passed as rvalue

[gcc-bugzilla at contacts dot eelis dot net]

Consider:

  #include <iostream>

  struct S
  {
    S(): i(2) {}
    S(S const&) {}
    int i;
  };

  void f(S x) { x.i = 0; }

  int main()
  {
    S y;
    f(static_cast<S&&>(y));
    std::cout << y.i << '\n';
  }

Expected output: 2
Actual output: 0

Thus, the assignment to the independent local variable x in f somehow modifies
y. That can't be right, not even with that static_cast to S&&, can it?


-- 
           Summary: function modifying argument received by-value affects
                    caller's variable when passed as rvalue
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gcc-bugzilla at contacts dot eelis dot net


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36744