Comparison of integer expressions of different signedness in dispatch.c on illumos

Compilation on OpenIndiana (illumos c5ef4e1ed4) produces the following warning:

In file included from ../../lib/isc/include/isc/list.h:14,
                 from ../../lib/isc/include/isc/types.h:30,
                 from ../../lib/isc/include/isc/mem.h:22,
                 from dispatch.c:21:
dispatch.c: In function 'dispatch_getnext':
dispatch.c:1432:18: warning: comparison of integer expressions of different signedness: 'int32_t' {aka 'int'} and 'unsigned int' [-Wsign-compare]
 1432 |  REQUIRE(timeout <= UINT16_MAX);
      |                  ^~
../../lib/isc/include/isc/assertions.h:44:11: note: in definition of macro 'ISC_REQUIRE'
   44 |  ((void)((cond) ||                                                  \
      |           ^~~~
dispatch.c:1432:2: note: in expansion of macro 'REQUIRE'
 1432 |  REQUIRE(timeout <= UINT16_MAX);
      |  ^~~~~~~

It seems to be related to the net manager dispatch branch, namely 8551ad02.