[commit] -Wunused warning in procfs.c (mips-irix only)

[Joel Brobecker <brobecker at adacore dot com>]

On mips-irix, the compiler is complaining that we are ignoring the
computed value in statements were we are using the praddset/prdelset
macros.  The definition of these macros look very similar to the ones
defined on systems such as sparc-solaris except for one important detail:
On sparc-solaris, the macros has a cast that casts the result to void.
Constract what we have on mips-irix:

        (((unsigned)((flag)-1) < 32*sizeof(*(sp))/sizeof(__uint32_t)) \
        && (((__uint32_t*)(sp))[((flag)-1)/32] |= (1L<<(((flag)-1)%32))))

... to what we find on sparc-solaris:
       
        ((void)(((unsigned)((flag)-1) < 32*sizeof (*(sp))/sizeof (uint32_t)) ? \
        (((uint32_t *)(sp))[((flag)-1)/32] |= (1U<<(((flag)-1)%32))) : 0))

The approach I took was to define two new macros gdb_praddset, and
gdb_prdelset that always cast the result to void, and then used that
instead of using the macros directly.  This avoids pointing casts
everywhere.
   
gdb/ChangeLog:
      
        -Wunused warning in procfs.c (mips-irix only).
        * procfs.c (gdb_praddset, gdb_prdelset): New macros.  Use them
        throughout instead of using praddset and prdelset respectively.

This allows us to compile this routine on mips-irix again.

-- 
Joel

2010-01-03  Joel Brobecker  <brobecker@adacore.com>

        -Wunused warning in procfs.c (mips-irix only).
        * procfs.c (gdb_praddset, gdb_prdelset): New macros.  Use them
        throughout instead of using praddset and prdelset respectively.

---
 gdb/procfs.c |   23 ++++++++++++++++-------
 1 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/gdb/procfs.c b/gdb/procfs.c
index e5df886..5791ee7 100644
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -270,6 +270,15 @@ typedef pr_siginfo64_t gdb_siginfo_t;
 typedef struct siginfo gdb_siginfo_t;
 #endif
 
+/* On mips-irix, praddset and prdelset are defined in such a way that
+   they return a value, which causes GCC to emit a -Wunused error
+   because the returned value is not used.  Prevent this warning
+   by casting the return value to void.  On sparc-solaris, this issue
+   does not exist because the definition of these macros already include
+   that cast to void.  */
+#define gdb_praddset(sp, flag) ((void) praddset (sp, flag))
+#define gdb_prdelset(sp, flag) ((void) prdelset (sp, flag))
+
 /* gdb_premptysysset */
 #ifdef premptysysset
 #define gdb_premptysysset premptysysset
@@ -281,14 +290,14 @@ typedef struct siginfo gdb_siginfo_t;
 #ifdef praddsysset
 #define gdb_praddsysset praddsysset
 #else
-#define gdb_praddsysset praddset
+#define gdb_praddsysset gdb_praddset
 #endif
 
 /* prdelsysset */
 #ifdef prdelsysset
 #define gdb_prdelsysset prdelsysset
 #else
-#define gdb_prdelsysset prdelset
+#define gdb_prdelsysset gdb_prdelset
 #endif
 
 /* prissyssetmember */
@@ -2219,7 +2228,7 @@ proc_trace_signal (procinfo *pi, int signo)
     {
       if (proc_get_traced_signals (pi, &temp))
 	{
-	  praddset (&temp, signo);
+	  gdb_praddset (&temp, signo);
 	  return proc_set_traced_signals (pi, &temp);
 	}
     }
@@ -2253,7 +2262,7 @@ proc_ignore_signal (procinfo *pi, int signo)
     {
       if (proc_get_traced_signals (pi, &temp))
 	{
-	  prdelset (&temp, signo);
+	  gdb_prdelset (&temp, signo);
 	  return proc_set_traced_signals (pi, &temp);
 	}
     }
@@ -3491,7 +3500,7 @@ procfs_debug_inferior (procinfo *pi)
 #else
   /* Register to trace hardware faults in the child. */
   prfillset (&traced_faults);		/* trace all faults... */
-  prdelset  (&traced_faults, FLTPAGE);	/* except page fault.  */
+  gdb_prdelset  (&traced_faults, FLTPAGE);	/* except page fault.  */
 #endif
   if (!proc_set_traced_faults  (pi, &traced_faults))
     return __LINE__;
@@ -4642,9 +4651,9 @@ register_gdb_signals (procinfo *pi, gdb_sigset_t *signals)
     if (signal_stop_state  (target_signal_from_host (signo)) == 0 &&
 	signal_print_state (target_signal_from_host (signo)) == 0 &&
 	signal_pass_state  (target_signal_from_host (signo)) == 1)
-      prdelset (signals, signo);
+      gdb_prdelset (signals, signo);
     else
-      praddset (signals, signo);
+      gdb_praddset (signals, signo);
 
   return proc_set_traced_signals (pi, signals);
 }
-- 
1.5.4.3