fbsd-nat: Pacify gcc with no functional changes

I see these errors on FreeBSD/aarch64 when using gcc 12 without passing
--disable-werror.

=====================================================================
  CXX    fbsd-nat.o
fbsd-nat.c: In member function 'void fbsd_nat_target::resume_one_process(ptid_t, int, gdb_signal)':
fbsd-nat.c:1208:11: error: unused variable 'request' [-Werror=unused-variable]
 1208 |       int request;
      |           ^~~~~~~
fbsd-nat.c: In member function 'virtual ptid_t fbsd_nat_target::wait(ptid_t, target_waitstatus*, target_wait_flags)':
fbsd-nat.c:1726:22: error: declaration of 'inf' shadows a previous local [-Werror=shadow=compatible-local]
 1726 |       for (inferior *inf : all_non_exited_inferiors (this))
      |                      ^~~
fbsd-nat.c:1697:17: note: shadowed declaration is here
 1697 |       inferior *inf = find_inferior_ptid (this, wptid);
      |                 ^~~
fbsd-nat.c: In member function 'virtual void fbsd_nat_target::detach(inferior*, int)':
fbsd-nat.c:2044:18: error: variable 'wptid' set but not used [-Werror=unused-but-set-variable]
 2044 |           ptid_t wptid = wait_1 (ptid, &ws, 0);
      |                  ^~~~~
cc1plus: all warnings being treated as errors
=====================================================================

This patch includes the following non-functional changes,

1. Remove unused variable "request".
2. Rename inf to inf_p to avoid shadowed declaration warnings.
3. Mark wptid as used when USE_SIGTRAP_SIGINFO is defined.

Tested on FreeBSD/aarch64 by rebuilding.

Approved-By: John Baldwin <jhb@FreeBSD.org>

1 files changed, 6 insertions, 5 deletions

diff --git a/gdb/fbsd-nat.c b/gdb/fbsd-nat.c
index 0ee3bcc..81a77b3 100644
--- a/gdb/fbsd-nat.c
+++ b/gdb/fbsd-nat.c
@@ -1205,8 +1205,6 @@ fbsd_nat_target::resume_one_process (ptid_t ptid, int step,
 
   for (thread_info *tp : inf->non_exited_threads ())
     {
-      int request;
-
       /* If ptid is a specific LWP, suspend all other LWPs in the
 	 process, otherwise resume all LWPs in the process..  */
       if (!ptid.lwp_p() || tp->ptid.lwp () == ptid.lwp ())
@@ -1694,9 +1692,9 @@ fbsd_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus,
 	  || ourstatus->kind () == TARGET_WAITKIND_NO_RESUMED)
 	break;
 
-      inferior *inf = find_inferior_ptid (this, wptid);
-      gdb_assert (inf != nullptr);
-      fbsd_inferior *fbsd_inf = get_fbsd_inferior (inf);
+      inferior *winf = find_inferior_ptid (this, wptid);
+      gdb_assert (winf != nullptr);
+      fbsd_inferior *fbsd_inf = get_fbsd_inferior (winf);
       gdb_assert (fbsd_inf != nullptr);
       gdb_assert (fbsd_inf->resumed_lwps != null_ptid);
       gdb_assert (fbsd_inf->running_lwps > 0);
@@ -2094,6 +2092,9 @@ fbsd_nat_target::detach (inferior *inf, int from_tty)
 			  }
 		      }
 		  }
+#else
+		  /* pacify gcc  */
+		  wptid = (void) null_ptid;
 #endif
 		  sig = 0;
 		  break;