------- Comment #13 from aoliva at gcc dot gnu dot org 2006-02-25 03:53 ------- It was GNU/Linux, for sure. Earlier gthr-posix.h used #pragma weak, which did not require declarations for referenced symbols, whereas the new weakref machinery requires earlier declarations to obtain the type for the weakref declaration.
-- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26309
