On 2022/3/17 11:22, Jakub Kicinski wrote:
On Wed, 16 Mar 2022 19:50:40 +0800 Guo Zhengkui wrote:
When I compile tools/testing/selftests/net/ by `make -C tools/testing/selftests/net` with gcc (Debian 8.3.0-6) 8.3.0, it reports the following warnings:
txtimestamp.c: In function 'validate_timestamp': txtimestamp.c:164:29: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'int64_t' {aka 'long long int'} [-Wformat=] fprintf(stderr, "ERROR: %lu us expected between %d and %d\n", ~~^ %llu cur64 - start64, min_delay, max_delay); ~~~~~~~~~~~~~~~ txtimestamp.c: In function '__print_ts_delta_formatted': txtimestamp.c:173:22: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'int64_t' {aka 'long long int'} [-Wformat=] fprintf(stderr, "%lu ns", ts_delta); ~~^ ~~~~~~~~ %llu txtimestamp.c:175:22: warning: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'int64_t' {aka 'long long int'} [-Wformat=] fprintf(stderr, "%lu us", ts_delta / NSEC_PER_USEC); ~~^ %llu
`int64_t` is the alias for `long long int`. '%lld' is more suitable.
That's on 32bit machines, I think what you need to use is PRId64. Or just cast the result / change variable types to long long.
But it should be '%ld' instead of '%lu', right?
Zhengkui