check_c_source_compiles("
            #include <jemalloc/jemalloc.h>
            int main() {
                unsigned narenas;
                size_t sz = sizeof(narenas);
                mallctl(\"arenas.narenas\", &narenas, &sz, NULL, 0);
                return 0;
            }
        " HAVE_JEMALLOC_ARENA_API)