Re: [PATCH 2/2] tests/tcg/x86_64: add vsyscall smoke test

[Ilya Leoshkevich]

On Mon, 2021-05-17 at 14:52 +0200, Cornelia Huck wrote:
> On Wed, 12 May 2021 06:02:50 +0200
> Ilya Leoshkevich <iii@linux.ibm.com> wrote:
> 
> > Having a small test will prevent trivial regressions in the future.
> > 
> > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> > ---
> >  tests/tcg/x86_64/Makefile.target |  6 +++++-
> >  tests/tcg/x86_64/vsyscall.c      | 11 +++++++++++
> >  2 files changed, 16 insertions(+), 1 deletion(-)
> >  create mode 100644 tests/tcg/x86_64/vsyscall.c
> 
> > diff --git a/tests/tcg/x86_64/vsyscall.c
> > b/tests/tcg/x86_64/vsyscall.c
> > new file mode 100644
> > index 0000000000..b9b7f87459
> > --- /dev/null
> > +++ b/tests/tcg/x86_64/vsyscall.c
> > @@ -0,0 +1,11 @@
> > +#include <stdio.h>
> > +#include <time.h>
> > +
> > +#define VSYSCALL_PAGE 0xffffffffff600000
> > +#define TIME_OFFSET 0x400
> > +typedef time_t (*time_func)(time_t *);
> > +
> > +int main(void)
> > +{
> > +    printf("%ld\n", ((time_func)(VSYSCALL_PAGE +
> > TIME_OFFSET))(NULL));
> > +}
> 
> Fails in https://gitlab.com/cohuck/qemu/-/jobs/1267727559 ("error:
> control reaches end of non-void function").

I always thought that omitting return in main() is allowed, but
turns out this is a C99-only thing. I should have probably used `make
docker-all-tests` instead of just `make check` to catch this.

I will send a v2.