When building selftests/timers with clang, the compiler warn about the function abs() see below:
posix_timers.c:69:6: warning: absolute value function 'abs' given an argument of type 'long long' but has parameter of type 'int' which may cause truncation of value [-Wabsolute-value] if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^ posix_timers.c:69:6: note: use function 'llabs' instead if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^~~ llabs
The note indicates what to do, Rework to use the function 'llabs()'.
Signed-off-by: Anders Roxell anders.roxell@linaro.org --- tools/testing/selftests/timers/posix_timers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/timers/posix_timers.c b/tools/testing/selftests/timers/posix_timers.c index 337424c5c987..73fb27901a1d 100644 --- a/tools/testing/selftests/timers/posix_timers.c +++ b/tools/testing/selftests/timers/posix_timers.c @@ -66,7 +66,7 @@ static int check_diff(struct timeval start, struct timeval end) diff = end.tv_usec - start.tv_usec; diff += (end.tv_sec - start.tv_sec) * USECS_PER_SEC;
- if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { + if (llabs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { printf("Diff too high: %lld..", diff); return -1; }
On Fri, Nov 5, 2021 at 9:34 AM Anders Roxell anders.roxell@linaro.org wrote:
When building selftests/timers with clang, the compiler warn about the function abs() see below:
posix_timers.c:69:6: warning: absolute value function 'abs' given an argument of type 'long long' but has parameter of type 'int' which may cause truncation of value [-Wabsolute-value] if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^ posix_timers.c:69:6: note: use function 'llabs' instead if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^~~ llabs
The note indicates what to do, Rework to use the function 'llabs()'.
Signed-off-by: Anders Roxell anders.roxell@linaro.org
Thanks for the patch! Reviewed-by: Nick Desaulniers ndesaulniers@google.com
I wonder why tools/testing/selftests/timers/adjtick.c redefines llabs when it already includes stdlib.h, and how that doesn't result in some kind of compiler diagnostic.
tools/testing/selftests/timers/posix_timers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/timers/posix_timers.c b/tools/testing/selftests/timers/posix_timers.c index 337424c5c987..73fb27901a1d 100644 --- a/tools/testing/selftests/timers/posix_timers.c +++ b/tools/testing/selftests/timers/posix_timers.c @@ -66,7 +66,7 @@ static int check_diff(struct timeval start, struct timeval end) diff = end.tv_usec - start.tv_usec; diff += (end.tv_sec - start.tv_sec) * USECS_PER_SEC;
if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) {
if (llabs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { printf("Diff too high: %lld..", diff); return -1; }
-- 2.33.0
On 11/5/21 2:44 PM, Nick Desaulniers wrote:
On Fri, Nov 5, 2021 at 9:34 AM Anders Roxell anders.roxell@linaro.org wrote:
When building selftests/timers with clang, the compiler warn about the function abs() see below:
posix_timers.c:69:6: warning: absolute value function 'abs' given an argument of type 'long long' but has parameter of type 'int' which may cause truncation of value [-Wabsolute-value] if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^ posix_timers.c:69:6: note: use function 'llabs' instead if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) { ^~~ llabs
The note indicates what to do, Rework to use the function 'llabs()'.
Signed-off-by: Anders Roxell anders.roxell@linaro.org
Thanks for the patch! Reviewed-by: Nick Desaulniers ndesaulniers@google.com
I wonder why tools/testing/selftests/timers/adjtick.c redefines llabs when it already includes stdlib.h, and how that doesn't result in some kind of compiler diagnostic.
Hmm. The define in /usr/include/stdlib.h is under #ifdef __USE_ISOC99 Maybe be that explains the reason for the definitions in the other two timers file?
Anders, I would like to understand this before I take this patch. I see you sent several patches to other tests as well. Would be useful at least understand why these defines exist.
thanks, -- Shuah
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