re PR tree-optimization/69162 (ICE in create_tmp_var, at gimple-expr.c:468)
PR tree-optimization/69162
* gimplify.c (gimplify_va_arg_expr): Encode original type of
valist argument in another argument.
(gimplify_modify_expr): Adjust for the above change. Cleanup.
* tree-stdarg.c (expand_ifn_va_arg_1): Use new 3rd argument
to determine the va_list type, build a MEM_REF instead of
build_fold_indirect_ref.