disruptive libffi upgrade

[Anthony Green]

Hello,

  I recently release libffi 3.0.11, and ABI changes are mandating a .so
  number change.  Despite the ABI change, I suspect that simple rebuilds
  are all that will be required for dependent packages.
 
  The ABI changes are simply:

1. Some internal debugging functions that should never have been
exported have been removed:

         void ffi_stop_here(void)
         void ffi_assert(char *expr, char *file, int line)
         void ffi_type_test(ffi_type *a, char *file, int line)

2. A new function has been introduced to support
   variadic functions (ffi_prep_cif_var).

  Libtool's guidelines for .so versioning mandate that I move from
  libffi.so.5.0.11 to libffi.so.6.0.0 (because functions have been
  removed).

  There are more than a handful of packages that depend on libffi, so
  I'm looking for advice on when to make this change.  Also, is there a
  convenient way to determine which packages in all of Fedora depend on
  libffi?  I would like to notify the maintainers that rebuilds will be
  required.  Or is there some other way to do this?

Thanks!

AG