extern void overflow_warning (tree);
extern void unsigned_conversion_warning (tree, tree);
extern bool c_determine_visibility (tree);
+extern bool same_scalar_type_ignoring_signedness (tree, tree);
#define c_sizeof(T) c_sizeof_or_alignof_type (T, true, 1)
#define c_alignof(T) c_sizeof_or_alignof_type (T, false, 1)