https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117387
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
But then later on it does:
/* Now possibly adjust the number of named args.
Normally, don't include the last named arg if anonymous args follow.
We do include the last named arg if
targetm.calls.strict_argument_naming() returns nonzero.
(If no anonymous args follow, the result of list_length is actually
one too large. This is harmless.)
If targetm.calls.pretend_outgoing_varargs_named() returns
nonzero, and targetm.calls.strict_argument_naming() returns zero,
this machine will be able to place unnamed args that were passed
in registers into the stack. So treat all args as named. This
allows the insns emitting for a specific argument list to be
independent of the function declaration.
If targetm.calls.pretend_outgoing_varargs_named() returns zero,
we do not have any reliable way to pass unnamed args in
registers, so we must force them into memory. */
if ((type_arg_types != 0 || TYPE_NO_NAMED_ARGS_STDARG_P (funtype))
&& targetm.calls.strict_argument_naming (args_so_far))
;
else if (type_arg_types != 0
&& ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
/* Don't include the last named arg. */
--n_named_args;
else if (TYPE_NO_NAMED_ARGS_STDARG_P (funtype)
&& ! targetm.calls.pretend_outgoing_varargs_named (args_so_far))
n_named_args = 0;
else
/* Treat all args as named. */
n_named_args = num_actuals;
/* Make a vector to hold all the information about each arg. */
args = XCNEWVEC (struct arg_data, num_actuals);
/* Build up entries in the ARGS array, compute the size of the
arguments into ARGS_SIZE, etc. */
initialize_argument_information (num_actuals, args, &args_size,
n_named_args, exp,
structure_value_addr_value, fndecl, fntype,
args_so_far, reg_parm_stack_space,
&old_stack_level, &old_pending_adj,
&must_preallocate, &flags,
&try_tail_call, CALL_FROM_THUNK_P (exp));