gdb/ChangeLog
2016-03-23  Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Pedro Alves  <palves@redhat.com>

	* exec.c (exec_file_locate_attach): Print warning for unsupported
	target_pid_to_exec_file.
	* remote.c (remote_pid_to_exec_file): Print warning for unsupported
	PACKET_qXfer_exec_file.
	* symfile-mem.c (add_vsyscall_page): Remove the "file" command
	message part.

diff --git a/gdb/exec.c b/gdb/exec.c
index 90811c0..a10ab9b 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -151,7 +151,13 @@ exec_file_locate_attach (int pid, int from_tty)
   /* Try to determine a filename from the process itself.  */
   exec_file = target_pid_to_exec_file (pid);
   if (exec_file == NULL)
-    return;
+    {
+      warning (_("No executable has been specified and target does not "
+		 "support\n"
+		 "determining executable automatically.  "
+		 "Try using the \"file\" command."));
+      return;
+    }
 
   /* If gdb_sysroot is not empty and the discovered filename
      is absolute then prefix the filename with gdb_sysroot.  */
diff --git a/gdb/remote.c b/gdb/remote.c
index af0a08a..4e44ffd 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -1311,7 +1311,10 @@ packet_ok (const char *buf, struct packet_config *config)
     internal_error (__FILE__, __LINE__,
 		    _("packet_ok: attempt to use a disabled packet"));
 
-  result = packet_check_result (buf);
+  if (strcmp (buf, "OK") == 0 && startswith (config->name, "vFile:"))
+    result = PACKET_UNKNOWN;
+  else
+    result = packet_check_result (buf);
   switch (result)
     {
     case PACKET_OK:
@@ -12977,7 +12980,12 @@ remote_pid_to_exec_file (struct target_ops *self, int pid)
   char *annex = NULL;
 
   if (packet_support (PACKET_qXfer_exec_file) != PACKET_ENABLE)
-    return NULL;
+    {
+      warning (_("Remote gdbserver does not support determining executable "
+		 "automatically.\n"
+		 "FSF gdbserver version 7.10 or later would support that."));
+      return NULL;
+    }
 
   if (filename != NULL)
     xfree (filename);
diff --git a/gdb/symfile-mem.c b/gdb/symfile-mem.c
index 8eb5176..79739a6 100644
--- a/gdb/symfile-mem.c
+++ b/gdb/symfile-mem.c
@@ -214,8 +214,7 @@ add_vsyscall_page (struct target_ops *target, int from_tty)
 	  format should fix this.  */
 	{
 	  warning (_("Could not load vsyscall page "
-		     "because no executable was specified\n"
-		     "try using the \"file\" command first."));
+		     "because no executable was specified"));
 	  return;
 	}
       args.bfd = bfd;