https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105061
--- Comment #1 from Will Wray <wjwray at gmail dot com> ---
Hmm, the accepted simplified version ^^^ with typename parameter removed
is then rejected if 'unsigned' is replaced with 'uint32_t' from <cstdint>
#include <cstdint>
template <int width, int offset>
struct uint_offset_bitfield { uint32_t : offset, field : width; };
| ^
| error: found ':' in nested-name-specifier, expected '::'
| ::
| error: invalid use of '::'
(and "error: invalid use of '::'" is just wrong - no use of '::' at all)
