-/* A mechanism for delayed evaluation. (Not sure if this is really necessary, so
- no detailed documentation on the "why".)
-*/
-int * _PDCLIB_errno_func( void ) _PDCLIB_nothrow;
+_Static_assert( ( (char)-1 < 0 ) == _PDCLIB_CHAR_SIGNED, "Compiler disagrees on _PDCLIB_CHAR_SIGNED." );
+_Static_assert( sizeof( sizeof( int ) ) == sizeof( _PDCLIB_size ), "Compiler disagrees on _PDCLIB_size." );
+
+_Static_assert( sizeof( _PDCLIB_wchar ) == sizeof( L'x' ), "Compiler disagrees on _PDCLIB_wchar." );
+
+_Static_assert( sizeof( void * ) == sizeof( _PDCLIB_intptr ), "Compiler disagrees on _PDCLIB_intptr." );
+
+_Static_assert( sizeof( &_PDCLIB_digits[1] - &_PDCLIB_digits[0] ) == sizeof( _PDCLIB_ptrdiff ), "Compiler disagrees on _PDCLIB_ptrdiff." );
+#endif