Extended Description

The following code does not get a vtable emitted when compiling with clang 5.0.0 (release_50@310398). Removing the 'using mozilla::B' line causes it to be emitted. The vtable is also emitted when not using '-g'

class FontInfoData;

class A {
void F(FontInfoData *aFontInfoData);
};

namespace mozilla {
struct B
{
A* mAttrs;
};
}

using mozilla::B;

using namespace mozilla;
class FontInfoData {
void Release() {
delete this;
}
virtual ~FontInfoData() {}
virtual void R();
};

void FontInfoData::R() {
}