Package: lib6
Version: 2.19-18+deb8u4
Severity: important
vDSO is not in effect in static linked executable on jessie. This is
not the case with wheezy.
We build binary to run on both wheezy and jessie, so -static. When
building platform is wheezy, vdso works fine, but jessie the opposite.
This leads to performance hit. Unfortunately, we use g++ 4.9 for some
application, so wheezy can't be used as build platform.
How to reproduce
$ cat t.c
#include <time.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/time.h>
int main()
{
struct timeval now;
gettimeofday(&now, NULL);
printf("%d\n", now.tv_sec);
printf("%d\n", time(NULL));
return 0;
}
$ gcc -static t.c
$ strace ./a.out
>From output, you can see syscall gettimeofday() is called.
