On Tue, Aug 02, 2022 at 03:12:40PM +0800, Jinrong Liang wrote: > From: Jinrong Liang <cloudliang@xxxxxxxxxxx> > > The following warning appears when executing: > make -C tools/testing/selftests/kvm > > rseq_test.c: In function ‘main’: > rseq_test.c:237:33: warning: implicit declaration of function ‘gettid’; did you mean ‘getgid’? [-Wimplicit-function-declaration] > (void *)(unsigned long)gettid()); > ^~~~~~ > getgid > /usr/bin/ld: /tmp/ccr5mMko.o: in function `main': > ../kvm/tools/testing/selftests/kvm/rseq_test.c:237: undefined reference to `gettid' > collect2: error: ld returned 1 exit status > make: *** [../lib.mk:173: ../kvm/tools/testing/selftests/kvm/rseq_test] Error 1 The man page says we need #define _GNU_SOURCE #include <unistd.h> which rseq_test.c doesn't have. We have _GNU_SOURCE, but not unistd.h. IOW, I think this patch can be diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c index a54d4d05a058..8d3d5eab5e19 100644 --- a/tools/testing/selftests/kvm/rseq_test.c +++ b/tools/testing/selftests/kvm/rseq_test.c @@ -9,6 +9,7 @@ #include <string.h> #include <signal.h> #include <syscall.h> +#include <unistd.h> #include <sys/ioctl.h> #include <sys/sysinfo.h> #include <asm/barrier.h> Thanks, drew > > Use the more compatible syscall(SYS_gettid) instead of gettid() to fix it. > More subsequent reuse may cause it to be wrapped in a lib file. > > Signed-off-by: Jinrong Liang <cloudliang@xxxxxxxxxxx> > --- > tools/testing/selftests/kvm/rseq_test.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c > index a54d4d05a058..299d316cc759 100644 > --- a/tools/testing/selftests/kvm/rseq_test.c > +++ b/tools/testing/selftests/kvm/rseq_test.c > @@ -229,7 +229,7 @@ int main(int argc, char *argv[]) > ucall_init(vm, NULL); > > pthread_create(&migration_thread, NULL, migration_worker, > - (void *)(unsigned long)gettid()); > + (void *)(unsigned long)syscall(SYS_gettid)); > > for (i = 0; !done; i++) { > vcpu_run(vcpu); > -- > 2.37.1 >