When using templates, A<AI>::f should not be reachable from main() because it
is protected.
The correct behavior is observed in the template-less version: the compiler
detects an encapsulation error.
% cat foo.cpp
#if NO_TEMPLATES == 1
class A { protected: int f() { return 42; } };
class B : public A { using A::f; };
int main() { B b; return b.f(); }
#else
template<int AI> class A { protected: int f() { return AI; } };
template<int BI> class B : public A<BI> { using A<BI>::f; };
int main() { B<24> b; return b.f(); }
#endif
% g++ -DNO_TEMPLATES=1 -o foo foo.cpp
foo.cpp: In function int main():
foo.cpp:2: error: int A::f() is protected
foo.cpp:4: error: within this context
% g++ -DNO_TEMPLATES=0 -o foo foo.cpp
% ./foo ; echo $?
24
--
Summary: using with templates breaks encapsulation
Product: gcc
Version: 4.3.3
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: sebastien at soja dot org
GCC build triplet: x86_64-linux-gnu
GCC host triplet: x86_64-linux-gnu
GCC target triplet: x86_64-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44956
