https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111309
--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- Yes, we should have APIs for building type-generic _BitInt interfaces (also a width-of operation to give the width in bits of an integer type; also type-generic versions of operations such as clz, ctz, parity, popcount that work to the width in bits of any unsigned operand). Though I suspect any library implementations of printf _BitInt support would end up needing architecture-specific workarounds for a while to avoid depending on having GCC new enough to support _BitInt in order to build a library with that support.