http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50982
--- Comment #38 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-11-05 16:31:36 UTC --- Well that's *really* strange. The declaration is a C++ function in C++ code, the extern "C" doesn't alter that, and void f() is identical to void f(void) in C++ (except that the latter has rightly been described as "an abomination" by Doug McIlroy and Dennis Ritchie) Does AIX have special rules in the C++ front end that cause an empty function parameter list to be considered a varargs function?!