Bug#914822: libwine:i386: missing printf output, without a printf failure

[Vincent Lefevre <vincent@vinc17.net>]

On 2018-11-27 18:59:26 +0100, Vincent Lefevre wrote:
> I do some tests of MPFR with MinGW, running the tests under wine
> (32-bit version). But sometimes, output from a printf is missing.
> 
> The MPFR code (in tests/tversion.c) is the following:
> 
>   if (printf ("[tversion] MPFR %s\n", MPFR_VERSION_STRING) < 0)
>     {
>       perror ("tversion (first printf)");
>       err = 1;
>     }
> 
> and at the end:
> 
>   return err;
> 
> so that if printf fails, the test will fail. But this is not the
> case: the test succeeds, even though output is missing, as shown
> by a diff on the generated file:
[...]

I forgot to say that output is not buffered:

  setbuf (stdout, NULL);
  setbuf (stderr, NULL);

from the tests_start_mpfr function (tests.c), called before the first
printf.

Just in case, there is also a test of errno at the end:

  if (errno != 0)
    {
      perror ("tversion");
      err = 1;
    }

It is also possible that the output occurred but was lost via the
script (e.g. in the pipe), but this would still be a bug.

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)