On 08.02.2014 14:34, Tony Houghton wrote:
On Sat, 08 Feb 2014 13:51:10 +0100
Klaus Schmidinger <klaus.schmidin...@tvdr.de> wrote:

          channels.c:45:119: warning: data argument not used by format string 
            snprintf(buffer, sizeof(buffer), rid ? "%s-%d-%d-%d-%d" : 
"%s-%d-%d-%d", *cSource::ToString(source), nid, tid, sid, rid);
~~~~~~~~~~~~~                                             ^

This is explicitly checked with 'rid ? ...', so the warning is
unjustified (although the compiler probably has a hard time figuring
that out ;-).

The warning is justified, because if rid is 0 it's still there as an
argument, but just happens to have a value of 0. I think you can make
snprintf "consume" it without printing anything by adding %.d to the
second format string.

I'm afraid not.
If I run

#include <stdio.h>
int main(void)
  for (int n = 0; n < 2; n++)
      printf(n ? "'%d-%d'\n" : "'%d%.d'\n", 1, 2);
  return 0;

I get


But maybe there *is* such a format character, it just isn't "%.d".

          eit.c:223:43: warning: comparison of constant 176 with expression of 
type 'SI::LinkageType' is always false
                           if (ld->getLinkageType() == 0xB0) { // Premiere World
                               ~~~~~~~~~~~~~~~~~~~~ ^  ~~~~

I assume this is because the enum LinkageType doesn't contain 0xB0.
However, the actual value that comes from the SI data may well be
0xB0, so I'm now typecasting uint(ld->getLinkageType()).

If 0xB0 has a significant meaning wouldn't it be a good idea to add it
to the enum?

You're probably right. Since there are already several "Premiere" related 
definitions in
libsi/si.h I guess it won't hurt to add yet another one. <rant>The DVB standard 
should never have
allowed all this "private" stuff...</rant>

          receiver.c:28:6: warning: indirection of non-volatile null pointer 
will be deleted, not trap [-Wnull-dereference]
               *(char *)0 = 0; // cause a segfault
          receiver.c:28:6: note: consider using __builtin_trap() or qualifying 
pointer with 'volatile'

Can you suggest a different way of causing a segfault at this point?

You could add volatile as the warning suggests. Is there a good reason
not to use abort() instead?

The idea behind this was to allow for easy backtracking in such a case.
I believe abort() wouldn't allow this, would it?


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