[Bug c++/21917] New: Missing warning? (or error?)

["igodard at pacbell dot net" <gcc-bugzilla at gcc dot gnu dot org>]

struct  virt { virt() : i(2) {} virt(int i) : i(i){} int i;  };
struct der1 : public virtual virt { der1(int i) : virt(i) {} };
struct der2 : public virtual virt { der2(int i) : virt(i) {} };
struct top : public der1, public der2 {
    top () : der1(0), der2(1) {} };
int main() { top t; }


Compiles without comment. However, the null constructor for "virt" is called
rather than the explicit constructor that is indicated by the constructor chain
from top. In fact, the der* constructors say " : virt(i)" but that
sub-constructor will never be called because virt is a virtual base class.

I don't know if it is actually an error to try to explicitly construct a virtual
base, but is sure is misleading and I think deserves at least a warning.

-- 
           Summary: Missing warning? (or error?)
           Product: gcc
           Version: 3.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: igodard at pacbell dot net
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21917