1.2.8 fails to build with gcc-13: 'uint32_t' does not name a type

I just tried to update to 1.2.8 on Gentoo and am getting a compile error with gcc-13 (only the first one shown here):

gtk.cc:38:18: error: 'uint32_t' does not name a type
   38 |     static const uint32_t MAGIC = 0x1A2AB40F;
      |                  ^~~~~~~~
gtk.cc:22:1: note: 'uint32_t' is defined in header '<cstdint>'; did you forget to '#include <cstdint>'?
   21 | #include "gtk.h"
  +++ |+#include <cstdint>
   22 | 

Indeed adding the explicit <cstdint> include fixes it. See https://gcc.gnu.org/gcc-13/porting_to.html for more info.