[Bug libffi/60073] [4.9 regression] 64-bit libffi.call/cls_double_va.c FAILs after recent modification

["amodra at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60073

--- Comment #7 from Alan Modra <amodra at gmail dot com> ---
The variadic support in libfii is fairly recent.  And yes, it might have been
there earlier if the testcases actually tested what they were suppose to test!

Note that powerpc64-gcc passes fp arguments corresponding to the ellipsis part
of variadic functions in both the parameter save area and fp registers,
contrary to the ABI which says they just go in the parameter save area if the
function has a prototype.  I think this was in part to satisfy libffi, where
without variadic support you don't know whether a function call is normal or
variadic and thus the powerpc libffi support had to pull fp values from fp
registers.  So we broke gcc (a little) to satisfy libffi..