http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53831
--- Comment #23 from Yuri Gribov <tetra2005 at gmail dot com> 2012-07-10 15:34:02 UTC --- The C++ Standard says that "an inline function shall be defined in every translation unit in which it is used" (n1905, 7.1.2). The test in question violates this rule: definition for C::f() is present only in impl.cpp. Should we consider the test invalid?