X-Authentication-Warning: delorie.com: mail set sender to djgpp-workers-bounces using -f
X-Recipient: djgpp-workers AT delorie DOT com
X-Authenticated: #27081556
X-Provags-ID: V01U2FsdGVkX1/BSPofTJjBtFJFySUpXsxwgGhhsEyQMUmpl+jcl5
	Tq8kheq9Wx82B7
Message-ID: <50BE6FD2.7090300@gmx.de>
Date: Tue, 04 Dec 2012 22:49:06 +0100
From: Juan Manuel Guerrero <juan DOT guerrero AT gmx DOT de>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121025 Thunderbird/16.0.2
MIME-Version: 1.0
To: djgpp-workers AT delorie DOT com
CC: Eli Zaretskii <eliz AT gnu DOT org>, Ozkan Sezer <sezeroz AT gmail DOT com>
Subject: Re: src/debug/fsdb/fullscr.c r1.12
References: <CAA2C=vA8kNDh=c5jXJ1r0TxVPuvKz-QViG222j=oDghS-UxeLA AT mail DOT gmail DOT com> <CAA2C=vD+ykMBRW2wBsSbgD83VjjediRt=eCZbMy4aQXS1fkG2g AT mail DOT gmail DOT com> <50BE474B DOT 9000204 AT gmx DOT de> <83ip8hr51z DOT fsf AT gnu DOT org> <CAA2C=vCdzUiS1c87eECfRjkbYXWn_B318oimm9gFSxGsRHbE2g AT mail DOT gmail DOT com> <83d2ypr2dw DOT fsf AT gnu DOT org>
In-Reply-To: <83d2ypr2dw.fsf@gnu.org>
Content-Type: text/plain; charset=ISO-8859-15; format=flowed
Content-Transfer-Encoding: 7bit
X-Y-GMX-Trusted: 0
Reply-To: djgpp-workers AT delorie DOT com

Am 04.12.2012 21:25, schrieb Eli Zaretskii:
>> Date: Tue, 4 Dec 2012 22:11:30 +0200
>> From: Ozkan Sezer <sezeroz AT gmail DOT com>
>>
>>> Why is it better to do this:
>>>
>>> 			    inst = unassemble_proper (j, &len);
>>> 			    (void) inst; /* set, but not used. */
>>>
>>> instead of this:
>>>
>>> 			    unassemble_proper (j, &len);
>>>
>>> Is it "verboten" to discard the return value of a function, for some
>>> reason?  Some exciting new "feature" of the latest GCC versions or
>>> something?
>>>
>> I kept the unused var only because it is referenced in the if 0'ed
>> out block. Otherwise, yours is just fine too. If your version is to
>> be preferred, then it is advisable to remove that if 0'ed out block
>> as well.
> IMO, if we want to ignore the return value, let's do that in the most
> natural way, which is not assign it to any variable.  Like we do with
> printf, for example, when we don't need its return value.
>
A new patch ignoring the return value of the function.

diff -aprNU5 djgpp.orig/src/debug/fsdb/fullscr.c djgpp/src/debug/fsdb/fullscr.c
--- djgpp.orig/src/debug/fsdb/fullscr.c    2012-12-01 04:29:46 +0000
+++ djgpp/src/debug/fsdb/fullscr.c    2012-12-04 22:21:24 +0000
@@ -855,11 +855,11 @@ select_source_file (char *file)

  static int
  code_skip (int origin, int count)
  {
    int len, *next, i, j, k, instcount, done, leave;
-  char *state, *source /* , *inst */;
+  char *state, *source;

    if (count >= 0)
      {
        while (count-- > 0)
      if (valid_instaddr (origin))
@@ -887,13 +887,11 @@ code_skip (int origin, int count)
          {
            done++;
            j = origin - done;
            if (valid_instaddr (j))
          {
-#if 0
-          inst = unassemble_proper (j, &len);
-#endif
+          unassemble_proper (j, &len);
            source = unassemble_source (j);
            next[done] = j + len;
            if (source)
              {
                leave = 0;
@@ -907,13 +905,13 @@ code_skip (int origin, int count)
                   code we don't need this.  */
  #if 0
                leave = (strncmp (inst, "jmp", 3) == 0
                     || strncmp (inst, "ret", 3) == 0
                     || strncmp (inst, "iret", 4) == 0);
-              if (!leave)
-                inst = unassemble_proper (j, &len);
  #endif
+              if (!leave)
+                unassemble_proper (j, &len);
              }
              }
          }
            else
          {