gdbserver, linux-low: add a couple of nullptr assertions.

This safeguards a couple of places that may theoretically return NULL but
must not in this specific context.  These were found by a static analysis tool.

Approved-By: Tom Tromey <tom@tromey.com>

diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index e1806ade82f076672d6a8d5e37b94b7ace315e71..40b6a907ad97bc072996f4215bb053cd943c62f6 100644 (file)
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -1169,6 +1169,7 @@ linux_process_target::attach (unsigned long pid)
   /* Don't ignore the initial SIGSTOP if we just attached to this
      process.  It will be collected by wait shortly.  */
   initial_thread = find_thread_ptid (ptid_t (pid, pid));
+  gdb_assert (initial_thread != nullptr);
   initial_thread->last_resume_kind = resume_stop;
 
   /* We must attach to every LWP.  If /proc is mounted, use that to
@@ -1198,6 +1199,7 @@ linux_process_target::attach (unsigned long pid)
       gdb_assert (lwpid > 0);
 
       lwp = find_lwp_pid (ptid_t (lwpid));
+      gdb_assert (lwp != nullptr);
 
       if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
        {
@@ -1572,6 +1574,7 @@ linux_process_target::detach (process_info *process)
     });
 
   main_lwp = find_lwp_pid (ptid_t (process->pid));
+  gdb_assert (main_lwp != nullptr);
   detach_one_lwp (main_lwp);
 
   mourn (process);
@@ -2512,6 +2515,7 @@ linux_process_target::wait_for_event_filtered (ptid_t wait_ptid,
   else if (filter_ptid != null_ptid)
     {
       requested_child = find_lwp_pid (filter_ptid);
+      gdb_assert (requested_child != nullptr);
 
       if (stopping_threads == NOT_STOPPING_THREADS
          && requested_child->status_pending_p